Karlstad University

Ramin Rahimi

Investigating the effect of in-store print advertising

on consumer’s visual attention using eye-tracking

technology

Master Thesis 30 Credits

Industrial Engineering and Management

Datum:

Handledare: Anders Gustafsson

II

Abstract

Due to rising number of products on the shelves of stores and the fact that about 70%

of buying decisions are made at the point-of-purchase, retailers and marketers are

growingly investing on in-store advertising material to grab their customers’ atten-

tion. Thus, measuring the effectiveness of the in-store material in catching consum-

ers’ attention would be highly of interest of marketers. In this study we have investi-

gated the priming effect of in-store print advertisement on the visual attention of

consumers. An experiment was conducted in a Swedish retail store where using eye-

tracking technology, the visual behavior of two groups of participants who had been

exposed to in-store product signs was captured. The results of this study shows that

participants who had looked at a product sign, noted (fixated at least once) that prod-

uct on the shelf earlier while the number of fixations on the target products was not

directly influenced. An implication for managers is that they can use in-store product

signs to manipulate the visual attention of consumers in a way that designated brands

are attended earlier.

III

Acknowledgments

I would like to thank the following people for their support during the work of this

Master’s thesis:

Anders Gustafsson - for introducing me to this project and supervising me, Erik

Wästlund - for managing the eye-tracking project, mentoring and helpful guidance,

Poja Shams - for helpful guidance and providing useful resources, Antonia Hall-

stensson - for helping during the data collection, ICA Maxi Bergvik - for providing

the experiment location, a special thanks to everyone who participated in the experi-

ment, and finally thanks to my family for their endless support.

Ali naghi V

Table of Contents

Abstract ............................................................................................................................................. II

Acknowledgments ........................................................................................................................ III

Table of Contents ............................................................................................................................ V

1 Introduction ............................................................................................................................ 7

1.1 Background .......................................................................................................................................... 7

1.2 Problem analysis ................................................................................................................................ 8

1.3 Purpose, research question, and hypothesizes .................................................................. 10

2 Theoretical framework .................................................................................................... 10

2.1 Relevance of theories ..................................................................................................................... 11

2.2 Human memory system ................................................................................................................ 12

2.3 Priming................................................................................................................................................. 13

2.4 Consumer information processing .......................................................................................... 13

2.4.1 Information processing ................................................................................................... 14

2.4.2 Exposure ................................................................................................................................ 15

2.4.3 Visual Attention .................................................................................................................. 17

2.4.3.1 Visual attention measurement ................................................................................................. 17

2.4.4 Top-down and bottom-up factors at the Point-of-Purchase ............................ 18

3 Method .................................................................................................................................... 19

3.1 Research approach ......................................................................................................................... 19

3.2 Eye-tracking technology .............................................................................................................. 19

3.3 Design and stimuli .......................................................................................................................... 21

3.4 Instrument .......................................................................................................................................... 23

3.4.1 Calibration ............................................................................................................................ 24

3.5 Participants ........................................................................................................................................ 24

3.6 Procedure ............................................................................................................................................ 25

3.6.1 Eye Tracking Metrics ........................................................................................................ 26

3.7 Validity, reliability, and ethical aspects ................................................................................ 26

3.7.1 Validity ................................................................................................................................... 26

3.7.2 Reliability .............................................................................................................................. 26

3.7.3 Ethical Aspects .................................................................................................................... 27

4 Results .................................................................................................................................... 28

5 Discussion ............................................................................................................................. 32

5.1 Managerial implications .............................................................................................................. 34

VI

5.2 Limitations and directions for future research ................................................................. 35

Bibliography .................................................................................................................................. 36

Appendix A ..................................................................................................................................... 41

The eye and its movements .......................................................................................................................... 41

7

1 Introduction

1.1 Background

In today’s cluttered retail environments, consumers seem overwhelmed by the num-

ber of competing products. While some of the consumer purchases are a result of

pre-planning, an increasing amount of the purchase decisions which according to

POPAI (1996) is 70% on average, are made at the point of purchase. This shift in

consumer behavior over the past two decades has changed the way the products are

designed, packaged, and marketed (Tonkin et al., 2011). Manufacturers use flashy

packaging design to make their brand more noticeable among its competitors and

retailers manage shelf space and special displays to draw attention to products and

brands that they want to sell (Pieters & Warlop, 1999). Such attempts are based on

the assumption that consumers’ attention and in-store brand choice are intimately

related and increasing visual attention as a primary stage in consumer choice pro-

cesses, will increase the choice likelihood (Pieters & Warlop, 1999). This is reasona-

ble since visual attention is an essential and often the only way to acquire infor-

mation about brands in consumer choice contexts (Pieters & Warlop, 1999).

Indicating that in-store visual attention increases brand consideration and choice like-

lihood naturally brings the issue of what influences in-store attention to mind (Chan-

don et al., 2011). According to Chandon et al. (2011), any observed behavior at the

point of purchase (e.g., brand consideration or choice) is influenced by both

memory-based (top-down) and visual factors (bottom-up) or what they call visual

lift. They define memory-based factors as “the part of consumer behavior attributa-

ble to factors residing in memory, such as brand preferences and visual lift as the

part of consumer behavior attributable to factors mediated by visual attention, such

as shelf location, number of facings, and price displays“. Visual factors are predomi-

nantly under the control of the retailer (Chandon et al., 2011).

While a growing proportion of marketing budgets are diverting from traditional out-

of-store media advertising to in-store advertising material (Egol and Vollmer 2008)

so that marketers and retailers make sure that their brands are seen at the point of

purchase, it has been difficult to measure the return on these investments (Chandon

et al., 2008). Since marketers usually use brand recall scores such as brand packag-

ing, in-store displays or shelf signage to gauge their P-O-P effectiveness (POPAI-

8

AISM, 1994), it is important for them to estimate the extent to which these recall

scores are driven by consumer in-store attention and not by brand familiarity, com-

petitive interference or category structures effects (Chandon, 2002). The traditional

approach for determining consumers’ visual attention behavior relied on response

accuracies and latencies in search tasks (Pashler et al., 2001). This has not been easy

since attention is an unobservable mental process, different attentional processes may

lead to the same search performance, and the same process may produce different

performances due to individual differences (Van Der Lans et al., 2008). Chandon et

al. (2009) find that self-reported recall of visual attention is not a valid proxy for ac-

tual visual attention to brands in a supermarket shelf display. They have indicated

their doubts about the validity of audience measurement tools and academic studies

using memory to infer exposure. In an earlier study Chandon et al. (2008) had identi-

fied most market research methods as inappropriate because they focus on evaluation

or choice once the alternatives being evaluated have captured consumer’s attention.

Since 83% of all the information processed by brain is received through the eyes,

realizing what customers are looking at can help us to understand the decision pro-

cesses (Wästlund et al., 2010). People need to move their eyes while they are looking

at a product or searching for a target. This means that we can observe their visual

behavior by recording their eye movements in every moment. Eye movements com-

prise measures of the unobserved visual attention process with a high temporal and

spatial resolution, and thus have the potential to yield insights about target search

that are hard to obtain otherwise (Findlay and Gilchrist 1998). In this study we ana-

lyze the eye movements of consumers while they choose a product category which

according to Pieters and Wedel (2004) has proved to be useful in development of

theories in advertisement effectiveness. For managers, our main result is that they

can persuade consumers note certain products faster hence using this opportunity that

around 70% of purchasing decisions are taken at the point-of-purchase.

1.2 Problem analysis

A considerable amount of academic literature has been generated assessing visual

marketing effectiveness using eye-tracking technology (Wedel and Pieters, 2008).

The studies have demonstrated the effects of both top-down and bottom-up factors

such as memory, involvement, attitude, spatial location of visual marketing stimuli or

basic features such as color, lines/edges. Yet, as noted by Wedel and Pieters (2008)

9

in their literature review much more evidence is needed for these factors and several

areas remain under-researched.

Being unprecedentedly affordable, now eye-tracking methodology may provide vis-

ual marketing research to achieve its full potential. Chandon and his colleagues

(2009) indicated that while eye-tracking studies in marketing are mostly done in an

advertising context, just a few have examined visual attention to supermarket

shelves. They add that because of the lack of research on effects of in-store market-

ing on visual attention and brand consideration, it has not been determined whether

the effects of in-store marketing on choice are mediated by enhanced attention and

consideration or whether they influence choice directly.

According to Egol and Vollmer (2008), during the last few years companies have

been increasingly investing in point-of-purchase advertising materials. Marketers

have found point-of-purchase as an ideal time and place to communicate with con-

sumers since it is the time and place at which many product and brand-choice deci-

sions are made (Shimp, 2007). Point-of-purchase advertising influences on consumer

behavior in different ways including encouraging or directing consumers’ brand-

choice decisions (Shimp, 2007). To our knowledge, there is no published paper on

the topic of in-store consumer priming in a real environment and a study gap in this

area is perceivable. The result of such research could be of high interest of marketing

researchers, retailers, and media companies who are concerned with the effectiveness

of marketing efforts.

Since arranging a store to meet experimental conditions and controlling many other

real-world variables is infeasible for the majority of typical controlled studies (Egol

and Vollmer, 2008), simulated environments have been used for the researches in

this area. According to Young (2005), the most important factor in achieving appli-

cable results is that the consumer must be kept in a shopping context. Lack of real-

ism has been a significant problem (noted or otherwise) in practically the entire con-

sumer shelf studies thus far (Tonkin et al., 2011) and review of some experiments by

Clement (2007) showed serious validity problems because they were in laboratory

experiments that poorly simulated real-world conditions. A supermarket has been

used as the experiment location of this study which distinguishes this study from

similar ones if any and can boost the validity of the results.

10

1.3 Purpose, research question, and hypothesizes

The purpose of this study is to examine the effect of point-of-purchase advertising

material on consumers’ visual attention. Using eye-tracking technology, we are at-

tempting to evaluate the priming effect of the in-store print advertisement on con-

sumers’ visual behavior and to investigate any relationship between them.

Based on the problem analysis and purpose of our study, our research question is the

following:

Does priming consumers through in-store print advertisement influence their

visual attention?

To answer this question we set up an experiment and formed a hypothesis to investi-

gate if consumers who look at a product sign in the store will note the related product

on the shelf faster. A second hypothesis was formed to investigate if looking at an in-

store product sign will make consumers fixate more on the related product on the

shelf.

2 Theoretical framework

In these chapter relevant theories about consumer visual behavior at the point-of-

purchase is presented. The literature reviewed and presented here is organized ac-

cording to the general conceptual framework in figure 2.1.

The following sections are designed to offer understanding of consumer information

processing as one of the higher stages of consumer decision making model, priming

and factors that construct and influence the consumer visual behavior at the point-of-

purchase. Not all of the consumer perception theories are covered here and the em-

phasis will be on theories and opinions that are relevant to our study and experiment.

11

Figure 2.1 General theoretical framework

2.1 Relevance of theories

The purpose of this study is to examine the change in consumers’ visual attention,

when searching for a product after being exposed to a print advertisement. The print

advertisement is supposed to prime the consumer to a certain product. The relevance

of each theory will be discussed in this paragraph; the theories will then be further

evaluated and explained under their separate headings in this chapter.

This chapter will continue with a brief explanation of human memory system which

helps to understand the priming theory that will be presented next. Then the consum-

er information processing theory will be introduced to show the process through

which consumers process the stimuli after receiving the information. The theory of

exposure is useful to understand how the preliminary process begins when a stimulus

Exposure

Visual Attention

Noting

Reexamination

Bottom-Up Factors

Stimulus-Based

Top-Down Factors

Memory-Based

Information Input

Priming

12

comes within the range of consumer’s sensory receptors. In this study the partici-

pants are first exposed to a product sign and then to the product category aisle.

Finally the attention theory, discussing how consumers allocate their mental pro-

cessing capacity to a certain stimulus is presented. This helps us to find out how in-

store and out of-store factors can influence the visual behavior of consumers and

how this influence can be measured. Theories that can offer additional knowledge to

understand the visual system exist in the appendix A.

2.2 Human memory system

During the last decades the computer metaphor has heavily influenced the thinking

about memory (Fennis and Stroebe, 2010). Human memory, in a similar fashion to a

computer, encodes the acquired information before it stores and retrieves them. By

encoding the information, the memory transforms the stimuli that they encounter into

a representation that can be stored. This process is shown in Figure 4.1.

Figure 4.1 Memory processes (Jansson, 2010)

Several theories of memory system conceive the memory as consisting of three sepa-

rate components: sensory memory, working or short-term memory and long-term

memory (E.g. Atkinson and Shifrin, 1968). Based on this model information is first

held briefly in a modality specific in sensory memory. Then a selection of this in-

formation through attention (which will be discussed later in this chapter) is trans-

ferred to the working or short-term memory, before an even smaller amount finds its

13

way to the long-term memory in consequence of rehearsal (Fennis and Stroebe,

2010).

Researchers have also suggested that memory can be categorized as conscious and

non-conscious memory which has been typically referred as explicit and implicit

memory respectively (Fennis and Stroebe, 2010). Explicit memory is outlined as an

individual's conscious recollection of facts or events (Schacter et al., 1993). Implicit

memory effects occur when performance on a task is facilitated in the absence of

conscious recollection and without us being aware of its influence on our perfor-

mance (Graf & Schachter, 1985).

2.3 Priming

Priming is the most widely approach to indicate the distinction between implicit and

explicit memory (Fennis and Stroebe, 2010). Priming refers to the phenomenon by

which previous experience (for example exposure to an object or a word) increases

the general accessibility of a conceptual or perceptual category in the mind and as a

result the likelihood of that category being used to interpret new information is in-

creased (Fiske and Taylor 1990). Since implicit memory is revealed when perfor-

mance on a task is facilitated in the absence of conscious recollection, performance

on implicit memory measures is revealed only when priming occurs (Sanyal, 1992).

Priming experiments typically have two (three) stages: Prime exposure followed by

the target stimulus in a seemingly unrelated context and finally analyzing the indi-

viduals behavior to determine the effect of priming (Sanyal, 1992). Priming can be

supraliminal or subliminal; In supraliminal priming participants exposure to the

prime is done as part of a conscious task while in subliminal priming the prime is

presented at very short exposure so that the participants are not consciously aware of

the prime (Fennis and Stroebe, 2010).

2.4 Consumer information processing

In today's consumer-oriented environments of most developed countries, marketing

information is found everywhere; in magazines, newspapers, on radio and TV, on the

internet and they are increasing (Bogart, 1984). A great deal of marketing infor-

mation exists in the stores including signs, point-of-purchase displays, shelf tags, and

advertisements in addition to information on packages. As it will be discussed later

in this study, consumers' exposure to the marketing information can be intentional or

14

accidental (Peter and Olson, 2008). In both cases since the working memory in mind

is limited (Miller, 1956), consumers cannot attend to all of the messages communi-

cated by those marketing stimuli they encounter, so how they select information,

attend to it, and process information from advertising? In the next chapters we try to

go through those topics.

2.4.1 Information processing

Information can be defined as the content of what is exchanged with the outside

world as we adapt to it or make our own adjustments to it (Wiener, 1964). Before

starting to process the information, it should be acquired. Consumers acquire infor-

mation from their environment through different stimuli. Stimuli are any physical,

visual or verbal communications that can influence a person's response (Assael,

1998). Two most important types of stimuli that influence consumer behavior are

marketing and environmental stimuli. Marketing stimuli are any communications or

physical stimuli that are designed to influence the consumers. The product and its

features (package, contents, physical properties) are primary stimuli and the commu-

nications that represent the product either through words, pictures, and symbolism or

through other stimuli associated with the product such as price or salespersons effect

are secondary stimuli (Assael, 1998).

We obtain the information from these stimuli through our senses: vision, hearing,

taste, smell, and touch. As shown in figure 4.3, a simple model of consumer infor-

mation processing involves exposure, attention and perception (comprehension)

stages (Mowen, 1995).

15

Figure 4.3 An information processing model (Mowen, 1995).

Information is received in the initial exposure stage through consumer’s senses. In

the attention stage consumers allocate processing capacity to stimuli and in the per-

ception or comprehension stage they interpret the information to realize its meaning.

Before explaining these stages in the next chapters I am going to introduce another

interesting information processing model called cognitive cycle which in a way is an

integration of the memory and information processing models previously discussed

earlier. According to Baars and Franklin (2003) cognitive cycle begins with the re-

ceiving of input through our senses, and continues with repeatedly selecting and

transforming the information by our cognitive system until it assumes a format we

can actually operate with. They estimate that a typical cognitive cycle take between 5

to 20 mille seconds meaning that we cycle 5 to 20 times per second or 300 to 1200

times per minute.

2.4.2 Exposure

Before any type of marketing stimuli can affect consumers, they must be exposed to

it which simply refers to the process by which the consumer comes in physical con-

tact with a stimulus. Thus, marketers need to make sure that consumers are exposed

to marketing stimuli (Hoyer& MacInnis1997). With exposure to a stimuli, one or

more of a consumer's sensory organs are activated and preliminary processing of

information is started (Assael, 1998). Two types of exposure to marketing infor-

16

mation can be distinguished: purposive or intentional and random or accidental (Pe-

ter and Olson, 2008). Some of the exposure to the marketing information happens

because of the consumers' own intentional, goal-directed search behavior (Peter and

Olson, 2008). Usually, consumers search for relevant information to help solving a

purchasing problem. For example someone who is in the market to buy a new cam-

era is more likely to look for camera ads or ask friends and colleagues for their expe-

riences. As the amount of marketing information in the environment increases, con-

sumers become more selective in their exposure to them meaning that consumers

actively choose whether to expose themselves to certain information or to avoid

them (Mowen, 1995). They often look for commercials that support their current

purchases in an attempt to justify them and ignore the information which might con-

test their needs or beliefs (Assael, 1998). After purchasing his or her desired camera

an individual may disregard the negative experiences of friends with the same cam-

era or may try to rationalize his purchase by reading positive reviews. The concept of

selective exposure can be of great interest to advertisers since consumers’ inclination

to selectively screen information to which they are exposed to or -as we will further

discuss-attend to can desperately reduce the effectiveness of the advertisement

(Mowen, 1995).

Surprisingly, according to many consumer search behavior investigations, the level

of intentional exposure to marketing stimuli is rather low (for example Beatty and

Smith, 1987). This limited search for information before purchasing a product hap-

pens either because consumers already have substantial product-related knowledge ,

meanings and beliefs stored in their memories or feel little involvement with the de-

cision (low self-relevance) (Peter and Olson, 2008). For example usually consumers

are not exposed to in-store advertisements through intentional search behavior but

most of the exposures occur as a result of consumers cruising in the store environ-

ment (Bloch And Ritchins, 1983). Consequently consumers may find new products

and sales promotions while browsing the store which indicates the powerful effects

of exposure to marketing information. Marketers can increase the probability that

consumers will be exposed to their marketing information in three ways: facilitating

intentional exposure, maximizing accidental exposure, and maintaining exposure

(Peter and Olson, 2008).

17

2.4.3 Visual Attention

Although we are potentially overwhelmed by marketing and environmental stimuli

which activate our sensory receptors during the exposure stage, not all of them will

receive further processing. This happens because of the limited capacity of our cog-

nitive resources resulting that it's impossible for us to process all the stimuli we are

exposed to at any given time (Engel et al., 1995). As a consequence, the cognitive

system is continually scanning the sensory information and choosing some of these

inputs for additional processing. This is referred as pre-attentive processing and hap-

pens at a preconscious level (Janiszewski, 1993). Those stimuli that pass through this

monitoring process enter into the second stage of information processing model, at-

tention, which can be defined as the process by which cognitive resources are allo-

cated to specific stimuli (Engel et al., 1995). While consumers in a store are exposed

to hundreds of stimuli, they just notice and momentarily focus on some of them.

2.4.3.1 Visual attention measurement

Visual attention as a ‘window’ that locally improves the speed and reduces the

threshold for processing events is declared as observable motor movements of the

eye and head (Pieters & Warlop, 1999). Therefor eye movements of the consumers

are good indication of visual attention. Eye movements consists of fixations during

which the eye remains relatively still for about 200-300 milliseconds, separated by

rapid movements, called saccades, which last around 20 to 100 milliseconds (more

detailed explanation of eye movements is presented in Appendix A). According to

Henderson and Hollingworth (1999), the “gist of the information” about a scene can

be extracted during the initial fixation. This means that consumers can identify the

semantic category of the scene (e.g., a supermarket shelf), its spatial layout (e.g.,

number of shelves), and the level of clutter during the first eye fixation. In applied

eye-movement studies, the first fixation on an object is known as “noting,” and the

second is known as “reexamination” (Chandon et. al., 2009).

Using eye-tracking methodology, researchers have shown that eye fixations, increase

memory for the fixated object e.g. a print advertisement (Pieters, Warlop, and Wedel

2002). Many eye-tracking studies distinguish between noting (making at least one

fixation on the object) and gaze duration (the total time spent looking at the object

over all of the fixations). The standard metric used by eye-tracking studies to meas-

18

ure the visual attention at the point-of-purchase is the percent of consumers noting

the object (Chandon, 2002). Since the length of time between the eye movements is

approximately constant, the total number of fixations on the object can be an indica-

tion of the gaze duration (Rayner, 1998).

However as Duchowski (2003) mentioned: a respondent’s thought might be any-

where other than where his visual focus. This means that eye-trackers can only track

the overt attention of an individual but not his or her covert attention. Hence we as-

sume that the attention is limited to the direction of focal gaze even though this

might not always be true (Duchowski, 2003).

2.4.4 Top-down and bottom-up factors at the Point-of-Purchase

Bottom-up factors are driven by the salience of the perceived stimuli. The salience of

stimuli is the degree by which it differs or stands out of its environment. We are

normally attracted by the most salient stimuli in our environment. These factors can-

not influence consumers without in-store visual attention. They typically include the

number of facings of the brand, its vertical and horizontal position in the display, and

in-store advertisement. Top-down factors driven by the current tasks we perform, the

action plans of these tasks and our goals (Scholderer, 2010). These factors cannot

influence consumers without memory activation and typically include consumer

shopping goal, purchase criteria, and demographics, and past brand usage (Chandon

et. al., 2009). At the point-of purchase consumer behavior is influenced by top-down

factors (e.g., brand awareness or goals) and bottom-up factors (e.g., shelf position

and number of facings). In order to be successful in today’s competitive retail envi-

ronments, marketers’ needs to influence customers based on both of these factors.

While the impact of top-down factors can be measured through surveys and by com-

paring the pre-store intentions and post-store choices, visual attention cannot be

measured in the same way. Measuring attention can help marketers to realize that

ineffective in-store marketing is due to poor attention getting ability- unseen and

hence unsold- or to a poor visual boost-seen yet unsold (Chandon et.al, 2008).

19

3 Method

This chapter begins with presenting the research approach. A short introduction of

eye-tracking technology then follows. Next chapters, present the research design and

stimuli used in this study. Then the specific eye-tracking instrument used for data

collection in this study, including the calibration process will be introduced. The

remaining sections explain the procedure of doing the experiment and applied visual

attention measures. The last chapter includes a discussion on the validity, reliability,

and the ethical aspects of the study.

3.1 Research approach

The research problem in this study, investigating the effect of in-store priming on the

visual attention of consumers, is deduced from existing theories, which according to

Bryman and Bell (2007) is referred to as a deductive methodological approach.

The main theme of this study is based on experimental method. The experimental

method is the best approach for the study of cause and effect relationship under con-

trolled conditions. In experimental research the cause and effect relationship is inves-

tigated by exposing one or more experimental groups to certain conditions and the

results are compared to those of other groups with different conditions. Though con-

ducting a truly experimental research is not easy, the results of this method of re-

search are considered more reliable (Phophalia, 2010). The experiment of this re-

search was done in ICA Maxi, A retail-store in Karlstad, Sweden and eye-tracking

methodology was applied for data collection. The data collection in this study was

done through a kind of systematic un-obtrusive observation which means that the

behavior of participants in a certain period of time was recorded without the interfer-

ence of the observer. Finally, IBM SPSS software was used to perform the quantita-

tive data analysis.

3.2 Eye-tracking technology

Eye-tracker is a common name for the measurement device used for measuring eye

movements. Generally there are two kind of eye movement monitoring techniques:

those that measure the position of the eye relative to the head, and those that measure

the orientation of the eye in space or the "point of regard" (Young & Sheena, 1975)

20

which this latter is typically used when the identification of elements in a visual sce-

ne is concerned. Recording the eye movements with high accuracy can be done in

several ways which three of the most common ones are: (1) EOG, electro-

oculography based, which measures electric potential differences around the eyes,

which vary with rotation. This method which was popular in the mid-1970s,

measures eye movements relative to the head and so is not generally suitable for

point of regard measurement unless head position is also measured, (2)SCL, scleral

contact lens based method which is one most precise methods also measures eye

movements relative to head position and uses a wire coil in a contact lens which is

then worn directly on the eye, (3) VIROG, video-based infrared oculography often

called infrared eye-tracking provides point of regard measurement and has become

more popular in market research and other applied settings (Duchowski, 2003).

Hence this method was used in this study it will be explained in more detail.

In general, Theses devices capture video images of the eye, process the video frames,

and output the eye's x- and y-coordinates relative to the screen being viewed. In or-

der to compute the point of regard in real time, video-based eye trackers use relative-

ly inexpensive cameras and image processing hardware. The apparatus may be table-

mounted or worn on the head as used in this study. The corneal reflection of an infra-

red light is measured relative to the location of pupil center. A series of four, so

called Purkinje, reflections are formed due to the construction of the eye, respective-

ly from the front and back of eye. Typical commercial eye trackers locate the first

Purkinje reflection off the front of the cornea which gives enough accuracy for point

of regard measurement. In order to eye movements from head movements two points

of reference on the eye are needed. The positional difference between the pupil cen-

ter and the corneal reflection changes with eye rotation, but remains relatively con-

stant with normal head movements. This feature allows fairly free head movements

during recording, making the measurement more unobtrusive (Duchowski, 2003).

While both table-mounted and light weight head-mounted eye-tracking systems have

been offered by various companies, the latter is particularly useful when the eye

movements are being recorded during unrestricted movement of people such as dur-

ing shopping tasks (Wedel & Pieters, 2008).

21

3.3 Design and stimuli

ICA Maxi, a retail store in Karlstad, Sweden, is the site where the experiment of this

study was performed. The experiment consisted a 2 (groups of respondents) * 2

(product signs) design. Each group of respondents was exposed to one of the product

signs. Products included two versions of the same brand of musli (Figure 3.1).

Figure 3.1 Two product signs (one at a time) were used for priming the participants

Two product signs, each in size of 59cm by 84cm were created for this study. The

Signs were installed (one at a time) on a column in the entrance of the product cate-

gory aisle, in a distance of 1.5 meter above the ground. The related products were

located on two adjacent shelves in second and third rows of a musli category aisle.

The distance between the product sign and related products was about 4 meters (fig-

ures 3.2 and 3.3).

22

Figure 3.2 the product ad was installed on a column in the entry of the aisle

Figure 3.3 Shelf lay out with the target products on two adjacent shelves highlighted

23

3.4 Instrument

In order to conduct this study, Tobii glasses, a mobile eye-tracking system that can

be used in retail locations was used. The eye-movements of the respondents were

captured through the monocular (right eye) camera integrated in the glasses. The

Tobii Glasses system includes a pair of eye tracking Glasses, a Recording Assistant,

optionally IR markers (not used in this study), and Tobii Studio eye tracking soft-

ware. The eye tracking glasses which looks like a pair of regular glasses capture

what the subject sees and record subject or user comments (see figure 3.4).

Figure 3.4 Tobii mobile eye-tracking glasses

The Recording Assistant records eye tracking data, sound, video, AOA snapshots,

and the position of the IR markers, and saves the data to a memory card. It guides the

user through the calibration of the participants – ensuring reliability and removing

subjective judgment – and displays information about eye tracking quality, battery

life and so on. The glasses connect to a recording assistant which participant takes

along on her trip through the store (see figure 3.5).

Figure 3.5 Tobii mobile eye-tracking system

24

Tobii Glasses are integrated with Tobii Studio – an eye tracking analysis and visuali-

zation software. Once the data is collected the SD card is removed from the record-

ing assistant and inserted into a computer with Tobii studio installed on, where the

data are projected on screen as gaze fixations and heat maps and can be analyzed.

3.4.1 Calibration

Before an eye tracking session starts, the glasses should be calibrated for every par-

ticipant's eyes. During calibration, the eye tracker measures characteristics of the

user’s eyes that are required to accurately calculate gaze direction. The experimenter

first asks the participant to stand at a distance of 1 m from a flat, vertical surface like

a wall and look straight ahead then sets the Recording Assistant at calibration mode.

Using an IR marker, the experimenter asks the participant to follow the green light

with the eyes (without moving the head) while he positions the IR marker at corre-

sponding points to the 3*3 grid displayed at the Recording Assistant screen. The cal-

ibration process for each participant takes 45 seconds in average.

3.5 Participants

84 participants were recruited for this thesis. Participants were chosen randomly

from the passing by people in front of ICA Maxi retail store entrance gate. The only

limitation for recruiting was that they shouldn't be using regular eye-glasses as they

had to remove their own glasses and wear the Tobii glasses eye-tracker which might

lead them not to see very well. 6 participants were exempted from further participat-

ing because of calibration issues (the calibration point at lower left corner of the grid

was particularly difficult for these participants to fixate on which might be a conse-

quence of the monocluarity-right eye only-of the Tobii glasses). 4 participants were

removed from the analysis as their data was not recorded, probably due to user fault.

14 more participants were removed later from the further analysis as it turned out

they never looked at any of the two target products or the product sign (in one case).

So the data of 60 participants was chosen for further analysis consisting of 25 males

and 35 female ranging from 15 to 85 years old with the median of 28.

25

3.6 Procedure

The 60 participants were divided into two groups based on the in-store sign they

were exposed to. Group 1 and group 2 respectively consisted of 29 and 31 partici-

pants. For simplicity we use the term Sign M1 and Product M1 to address the sign

and product related to group 1 and the term Sign M2 and Product M2 to address the

sign and product related to group 2.

After finishing the calibration, the participants who were successfully calibrated

were asked some basic demographic questions and also about their shopping habits

(Age, gender, household number, whether using shopping list, shopping frequency,

etc.). Then the experimenter set the Recording Assistant in recording mode and de-

clared the participant number (corresponding number to the questioner for later

recognition of the participant). Then the experimenter asked the participant to hold

the Recording Assistant while guiding them to the store. The participants were told

to follow the experimenter. When they reached at about a distance of 2 meters from

the sign, the experimenter asked "if the participant could see the product sign"

hanged on a column at the entrance of the product category aisle and then instructed

the participant to go to product aisle and choose one product and give it to the exper-

imenter (see figure 3.6). Something that should be mentioned here is that in order to

remove any bias in the participants they were asked “if they could see the product

sign” rather than being directly told to look at the product sign.

Figure 3.6 the participants were asked to choose a product after being exposed to a

product sign

26

3.6.1 Eye Tracking Metrics

A large number of metrics can be derived from eye-movement data and a host of

measures is being now used in psychology, engineering, and marketing (Rayner,

1998). The metric of interest in this study was the fixation order on the target prod-

ucts. This metric was used to determine which product was noted first. The main

interest of this study is to investigate if priming effects can change the order of fixa-

tion on the target products by participants.

3.7 Validity, reliability, and ethical aspects

3.7.1 Validity

According to Kumar (2005) a common definition of validity in terms of measure-

ment processes is the ability of an instrument to measure what it is designed to

measure. This study mainly aims to evaluate the visual attention of the participants in

a retail-store. This was achieved by gauging the eye fixations of participants using

eye-tracking technology. Since eye fixations are necessary for object identification in

supermarket shelves, their location is a good indication of visual attention (Chandon

et.al, 2009) which increases the validity of this study.

To achieve ecological validity, it's necessary that participants remain immersed in a

shopping context during the entire experiment (Tonkin et. al., 2011). Chandon et al.

(2009) found serious validity problems in reviewed laboratory experiments where

real-world conditions were poorly simulated. Immersion can be preserved through

proper priming, environmental cues, and visual stimuli (Tonkin et. al., 2011). The

experiment of the present study was conducted in a supermarket with random cus-

tomers as participants who highly increase the ecological validity. To increase the

face validity of the study, the printed advertisements used had no promotional feature

and were just informational. Additionally the target products were chosen from the

same brand with the little package difference to remove any visual saliency.

3.7.2 Reliability

The extent to which a questionnaire, test, observation or any measurement procedure

produces the same results on repeated trials is called reliability. In short, it refers to

the stability or consistency of scores over time or across raters (Bryman, 2012).

27

Some of the things which can make the reliability low in the research studies are

wrong samples, problems in interpretations and problems with standardization in the

interviews etc. (Kumar, 2005)

To make sure that the data collected by the eye-tracker from each participant in this

study is reliable, all of the participants should undergo a calibration process before

beginning the data collection. The calibration process is explained in more detail in

the method section of this study. In case, the calibration process does not go well, the

potential participant should be exempted from the experiment.

The analysis of the recorded videos in this research was done visually. In all cases

where the fixation location was not easy to detect, the opinion of an eye-tracking

expert was obtained to increase the reliability of measures.

Another issue that should be considered concerning reliability is the interaction be-

tween experimenter and participant and the exact wording used during priming. In

the discussion chapter of this study, the exact wording used for priming the partici-

pants is argued in more detail. However, reliability of this study might still be en-

hanced by increasing the number of participants.

3.7.3 Ethical Aspects

Ethical aspects regarding the participants' dignity and welfare was considered during

the recruiting and data collection processes of this study. Fortunately the participants

in this experiment were not subject to any direct or indirect risk or adverse conse-

quences. However the participants' consent was obtained before conducting the ex-

periment and they were clarified about the general aim of the study. They were in-

formed that they should wear eye-tracking glasses during the experiment which rec-

ords their voice and gaze (whatever they look at) and they were free to decline the

participation (which some of the participants did because they didn't like to walk in

the store with the glasses). After the data was collected the participants were provid-

ed with more information about the purpose and benefits of the research and a lottery

ticket with value of 10 SEK to appreciate their participation.

28

4 Results

The primary measure of interest in this study was the order of fixations on the target

products within the participants of each group. A Chi-square test shows that the two

groups were significantly different in their fixation order (df = 1, p<0.05),

indicating that participants within each group first noted the product that they had

been exposed to its sign at the point of purchase. The descriptive results are shown

graphically and descriptively in figures 4.1 and 4.2 and table 4.1. Figure 4.3 shows

the same result in percentage.

Figure 4.1 Group 1 fixation order on the target products

19 10

29

05

101520253035

Participants who firstfixated on the primed

product

Participants who firstfixated on the other

product

TotalNu

mb

er o

f P

arti

cip

ants

Group 1

20 11

31

05

101520253035

Participants who firstfixated on the primed

product

Participants who firstfixated on the other

product

TotalNu

mb

er o

f p

arti

cip

ants

Group 2

29

Figure 4.2 Group 2 fixation order on the target products

Figure 6.3 Percentage of participants’ fixation order in each groups

Table 6.1 Summary of results and Chi-square analysis of target products fixation

order

Another measure used in this study was the total number of fixations on the target

products made by the participants of each group. The result which is shown in table

6.2 displayed a non-significant trending in the predicted direction indicating a higher

fixation number on the primed products ( =1.959, df = 1, p>0.1).

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Group 1 Group 2

Per

cen

tage

of

Par

tici

pan

ts

Percentage of participantswho first fixated on theother product

Percentage of participantswho first fixated on therelated product

Variable n M1 M2 2 p

Product ad. 5.406 <0.05

Sign M1 29 19 10

Sign M2 31 11 20

Totals 60 30 30

Product First Fixated

30

Figure 4.4 Number of fixations on the target products in group 1

Figure 4.5 Number of total fixations on the target products in group 2

Table 4.2 Summary of results and Chi-square analysis of target product total fixation

numbers

31

Additionally, we analyzed the number of fixations on the target products by partici-

pants within each group who had first noted the primed product. Results show that

these two classifications were significantly different in their observations of the tar-

get product (

=8.8153, df = 1, p<0.005), indicating that participants within each

group had more fixations on the product that had noted first. The results are shown

graphically in figure 4.6 and table 4.3 presents the summary of the results and Chi-

square analysis.

Figure 4.6 Number of fixations on the target products by the participants who had

first noted product M1

Figure 4.7 Number of fixations on the target products by the participants who had

first noted product M1

32

Table 4.3 Summary of results and Chi-square analysis of target product fixation

numbers between participants within each group who had first noted the primed

product

5 Discussion

This study investigated the potential influence of point-of-purchase advertising-in the

form of product sign on visual attention of consumers using eye-tracking technology.

To our knowledge, it is the first study that demonstrates the relationship between in-

store priming and visual behavior of consumers using a retail store as the experiment

location which can highly contribute in the validity of the collected data. This study

is in particular of interest of marketers and researchers who want to measure the val-

ue of the point-of-purchase advertising material.

The main result of this study is that in-store print advertisements can influence the

visual attention of consumers. The participants, who had been exposed to a product’s

sign, noted that product in the shelf earlier than the other target product. If we can

generalize this, it means that seeing a product’s sign at the point-of-purchase can lead

customers to attend to it earlier than other products. Eye-tracking studies by Pieters

et al. (2002) have shown that eye fixations, but not peripheral vision, increase

memory for the fixated object. While generally the memory effect is considered for

top-down factors, since the aim of the present study is not examining the saliency of

the product itself but investigating the effect of exposure to the print advertisement

on visual attention in a short time interval, again the role of memory can be consider-

able. But the type of memory we are dealing with here is sensory and short-term

memory rather than long term memory which is more suited for out of-store factors.

As mentioned in the theory section, this increased memory for the fixated object

might lead to a later response bias which will be explained here.

33

When consumer is exposed to a visual marketing stimulus, the information received

through vision is stored in the sensory stores for a short period after the end of stimu-

lation. A selection of this information is later transferred to short-term memory

through attention. This increased memory (and especially implicit memory as men-

tioned in the theory section) causes a preference for previously exposed information

which can lead to perceptual fluency. In perceptual fluency a previously seen stimu-

lus for example a product in the shelf in lack of a successful memory search is at-

tributed to a product preference instead of a former exposure.

Another possible explanation for this can be the priming effects theory which states

previous exposure to an object, called the prime, (the product sign in this study) can

alter the perception and interpretation of a second target stimulus (the product cate-

gory aisle in this study) buy increasing its accessibility in mind. In fact, exposure to

the product sign, through increasing mind’s accessibility to perceptual category, in-

creases the likelihood of using the gained information for interpreting and influenc-

ing the information from the target products leading to faster attention to it.

The total number of eye-fixations on the target products by each group was also ana-

lyzed in this study. The number of eye fixations which can be an indication of gaze

duration is used to measure the amount of in-store visual information processing.

The results did not show any significant relationship between looking at the print

advertisement and the number of eye fixations on the related products on the shelf.

By the way it was not surprising that being exposed to the in-store print advertise-

ment did not influence the amount of information processing. A reason for this might

be that unlike noting that is based on a combination of out-of-store and in-store visu-

al characteristics of the objects in the scene, reexamination is influenced more by the

informativeness of the object for the task at hand (e.g., brand preferences). This

means that consumers might more rely on their prior knowledge for reexamining the

products on the shelf. According to Chandon et al. (2009) even if in-store marketing

draws consumers’ attention to a brand that they have never used, it is unlikely that

they choose it because such brands are likely to have been permanently eliminated

from consideration.

By the way two products used in the study were from the same brand with incremen-

tal visual and natural differences which were positioned in two adjacent rows of the

shelf. It is likely that if the products used in the experiment were more different or

were located further apart the result of the total number of eye fixations were differ-

34

ent. However, we had two use products from the same brand, with little visual differ-

ence and locate them close for the noting measure. Obviously more research is need-

ed to investigate the consumers’ behavior in reexamining the brands on the shelves.

Additionally our results show that participants who had first noted the product that

had been previously exposed to its print advertisement, made more eye fixations on

the noted product than the other one. This means that the product that was noted ear-

lier was fixated more than the product that was noted later. Previously Chandon

(2002) had found that making one eye fixation to a brand displayed on a supermarket

shelf is enough to create direct and indirect priming effect which leads to more eye

fixations on the noted product. Our results shows that the order of noting a product

can also influence on the number of eye-fixations on that product and can lead to

higher number of fixations to the earlier noted product which means a higher amount

of visual information processing. Hence our results show that being exposed to the

product in-store print advertisement can indirectly influence on the number of eye

fixations on that product through influencing the order of noting the brands.

5.1 Managerial implications

Thousands of products on the shelves are competing to attract consumers’ attention

inside the stores where consumers make most of their choice decisions even though

just a fraction of the products successfully get attention. Marketers and retailers are

growingly investing on in-store marketing material to take advantage of this oppor-

tunity. Hence assessing the effectiveness of point-of-purchase advertising material is

of highly interest to justify these investing. Our findings show that marketers can use

print advertisement at the point-of-purchase to manipulate consumers’ attention.

Through this manipulation they can make their customers to note certain products

earlier than other products. Previous studies by Chandon et al. (2009) has confirmed

that efforts made to improve the consumer attention should positively influence the

consumer behavior at the point of purchase.

Additionally results of this study suggest that looking at the in-store print advertise-

ment can at least indirectly lead to more visual information processing of the related

products on the shelves. While we cannot claim that all in-store attention might lead

to choice, it’s for sure that products that are not seen will be unsold which shows the

significance of improving visual attention attempts.

35

5.2 Limitations and directions for future research

The findings in this report are subject to at least three limitations. First, since the

participants were needed to wear the Tobii eye-tracking glasses during the experi-

ment, they should have been able to see clearly without regular glasses. Therefore all

the prospective participants who wear regular glasses or couldn’t see well without

them were exempted from the experiment of current study.

Second, for some reasons we were not able to use the IR markers which come with

the Tobii eye-tracking package and are used for software analysis of the recorded eye

movements. Hence the analysis of the recorded videos in this experiment was done

visually. By the way, in the cases where the eye fixations of the participants were not

easily identifiable and were subject to more precise judgments, the opinion of an eye-

tracking expert was employed.

Third, during the experiment the participants were asked to look at the product sign.

This was done to make sure that participants see the advertisement (otherwise their

data would have been removed from the analysis). But when consumers are asked to

look at an object, they might think that they are supposed to find that product in the

shelves which if true it can undermine the validity of the results of the experiment.

Maybe the experiment could be done without asking the participants to look at the

advertisement, but in that case many more participants should have been recruited

(since many might not look at the ad and be removed from the study) which is really

time and cost consuming. In order to reduce the bias the question was asked in a way

that consumers see the ad as a benchmark to find the product category shelf and not

the product itself. This was done in a way that creates the least bias on consumers.

The exact terms used were: “Do you see that product (Musli) sign there? Behind that

sign is the Musli aisle, please go there and pick up a Musli”.

This paper can serve as a base for future studies. In this study we examined the effect

of advertising at the point- of-purchase on consumer visual attention which is one of

the stages in consumer decision making at the point of purchase. In the other way

this study does not directly examines the priming effect on sales of the product. Fu-

ture studies can continue this experiment to the point that examines consumers’

choice of product after considering various products. A further study could also do

the same experiment while using other metrics for eye-movement analysis. For ex-

ample a study could use the fixation duration as a measure for the analysis.

36

Additionally future studies can be done in a similar way with using another type of

in-store marketing material instead of print advertisements. For instance one research

could be analyzing the effect of in-store audio or video advertising on consumer vis-

ual attention.

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41

Appendix A

The eye and its movements

Light enters the human eye through the cornea, and then the lens located behind the

cornea turns the image upside down and projects it onto the back of the eyeball-

retina. The retina is filled with light-sensitive cells which transduce the incoming

light into electrical signals and send it visual cortex for further processing through

the optic nerve. The place where the optic nerve exits the eye is called the blind spot

as there is no vision at that location. There are two types of cells in the retina, rods

and cons. Rods are light sensitive and support vision under dim light conditions.

Cones are sensitive to what is called visual detail and provide us with color vision.

Between the cornea and the lens, is iris which consists of a ring of muscles with the

pupil in its center. These muscles adjust the size of the pupil-normally from 2mm to

8 mm -to maintain a constant level of light on retina in various conditions. The pupil

dilates in dimmer light, for a wider visual angle or for a smaller depth of focus and it

constricts in brighter light, for a narrower visual angle or for a larger depth of focus

(Vilis, 2008).

As can be seen in the figure 4.4, there is a small area directly opposite to the lens

called the fovea. While cons are sparsely dispersed in the periphery of the retina,

they are over-represented in this small area. This makes the fovea responsible for

high resolution in two degrees of the visual field which is about twice the width of

our thumbnail at arm's length. Since we have full acuity only in this small area, in

order to see a selected object sharply, we have to move our eyes, so that light from

that object falls directly on the fovea. Due to a decrease of photosensitive cells, acui-

ty declines in the periphery and parafovea of the retina. The limited range of high

acuity vision across the retina makes it necessary to move the eyes in order to project

the specific and small parts of the visual field on the fovea and thereby available for

further processing. Six muscles (three pairs) attached to the eye control the eye

movements. They are responsible for three-dimensional (horizontal, vertical, and

torsional) movements of the eye inside the head. These muscles are controlled by

large parts of the brain so they direct the gaze to relevant locations in space

(Holmqvist et.al, 2011).

42

Figure 4.4 Cross section of human eye

What seems to be smooth movements of eyes actually consists of fixations during

which the eye remains relatively still for about 200-500 milliseconds, separated by

rapid movements, called saccades, which last around 20 to 100 milliseconds. Vision

(especially of high spatial resolution) is suppressed during a saccade while a contig-

uous area of the scene is projected onto the fovea for detailed visual processing dur-

ing a fixation (Rayner, 1998).

The fact that new information is only acquired when the eye remains still over a pe-

riod of time, fixations are the most reported event in eye-tracking data. It is generally

believed that when we measure a fixation, the attention to that position is also meas-

ured, even though there are some exceptions that make them apart (Holmqvist et.al,

2011).

43