RESEARCH IN PSYCHOLOGY

The Scientific Method

SCIENTIFIC METHOD Theory Hypothesis Research Support the theory OR Refute/Fail

THEORIES Explanation based on observations How a phenomenon (observable thing)

works Interconnected ideas/concepts Used to explain prior observations or

make predictions about future events

HYPOTHESIS Prediction based on a theory Specific, testable Outcome should support the theory

RESEARCH Collection of data Objective information/measurements

THE SCIENTIFIC METHOD IN ACTION Theory

Alcohol impairs driving ability Hypothesis

People who consume alcohol tend to display poorer coordination and motor skills than those who don’t

ResearchObserved two groups – one drinks alcohol,

the other doesn’t Analyze data

Use statistical techniques

VARIABLE Something that can vary that the

researcher can measure or manipulateFor the previous study some variables

would be: Amount of alcohol consumed Level of intoxication Coordination Motor control Balance

OPERATIONAL DEFINITIONS Identifying variables so they can be

measuredCoordination

How easily people can touch their fingers to their nose with their eyes closed?

The number of inches by which they miss by

TYPES OF STUDIES

Descriptive

Longitudinal

Cross-Sectional

1. DESCRIPTIVE Observational

Observing and noting behavior Analyzing behavior objectively

Two types of observation:Naturalistic

Observer is separate from the situationParticipant

Becomes one of the participants

2. LONGITUDINAL Examine change over time Study or follow the same participants

multiple times over a period of time

Advantages: Provide info. about the effects of age on the

same peopleDisadvantages:

Expensive Takes a long time May lose participants over time

3. CROSS-SECTIONAL Compares participants in different

groups at the same timeAdvantages:

Quick and less expensiveDisadvantages:

Unidentified variables may be involved

BIASObserver (experimenter) Bias

Participant Bias

BIAS Tendency or inclination Prevents unprejudiced consideration of

a question or idea

OBSERVER BIAS Errors in observation that occur because

of an observer’s expectationsA study was conducted on male and female

facial expressions when viewing a slide show

The study was trying to prove that men and women show the same emotional expression

If the observer believes women are more emotional than men, he/she may always observe emotional expressions on women and not on the men

PARTICIPANT BIAS When a person in a study knows what

the observer is looking for they may change their behavior to fit the observer’s expectancySometimes done on purposeSometimes unintentional

CORRELATIONAL STUDIES How variables are naturally related Does not show causation

Amount of alcohol available in a community and the likeliness of car accidents

Advantages: Rely on naturally occurring relationships Take place in real world settings

Disadvantage Cannot show causal relationships Unidentified variables may be involved

EXPERIMENTSA study that tests causal

hypotheses by measuring and manipulating variables

GROUPS Control

Comparison groupParticipants who do not receive any

intervention

ExperimentalTreatment groupReceive intervention

EXAMPLES Study on violent videos games and

whether they encourage violent behaviorControl Group:

Plays a non-violent gameExperimental Group:

Plays a violent game

Study on how people are affected by alcohol useControl Group:

Drinks waterExperimental Group:

Drinks alcohol

VARIABLESIndependent

Dependent

INDEPENDENT (IV) Variable that is manipulated

The amount of intoxication

Examines the impact on the dependent variable

DEPENDENT (DV) Variable that is affected by the

manipulation of the IVDriving performance after intoxication

RANDOM SAMPLING Results should generalize or apply to

people beyond those in the study

Sampling Process by which you select people from the

population

Random Sampling Represents the populationEqual chance of being chosen

RANDOM ASSIGNMENT Placing research participants into the

conditions of an experiment in a way that each participant has an equal chance of being assigned to any level of the IV

DATA COLLECTION

METHODS

OBSERVATION View behavior Write descriptions Tallies Ratings on a scale

CASE STUDY Intense examination of a very specific

group or type of peopleBrain injuriesPsychological disorders

SELF-REPORT Questionnaires Surveys

DisadvantagesBiasNever return surveys

AdvantagesEasily administeredMailed outGather data from a large amount of people

THE HAWTHORNE EFFECT Hypothesis: Being observed can lead

participants to change their behavior

Independent Variables – pay incentives, break schedules

Dependent Variable – speed of production

RESULTS – Workers’ productivity increased when they were being observed, regardless of the change in the IV

CONCLUSION: Being observed can lead participants to change their behavior because people act in particular ways to make positive impressions

ETHICAL CONCERNS

Ensure participants well being

INSTITUTIONAL REVIEW BOARDS Strict guidelines Review all research proposals Make sure it meets scientific standards Must take into consideration ethical and

safety concerns Well being of the participants

CONCERNS Privacy

Names are never published Access to data

Only the researcher and his/her team Informed consent

Overview in writingGive relevant informationHave the right to know what they will

experienceAcknowledge their participationSignature on the form