the behavioralist as dietician: leveraging behavioral economics to improve child food choice and...

The Behavioralist as Dietician: Leveraging Behavioral Economics to Improve Child Food Choice

and Consumption

John A. List and Anya C. (Savikhin) Samak

November, 2012

Thanks to the Greater Chicago Food Depository and the Kenneth and Anne Griffin Foundation for generous funding of this research. The views expressed in this paper do not represent the views of our funding sources.

BEHAVIORALIST AS DIETICIAN: LEVERAGING BEHAVIORAL ECONOMICS TO IMPROVE CHILD FOOD CHOICE | SAMAK, A.

Need to Address Decision-Making by Children and Adolescents

• Tendency to consume an unhealthy diet is learned at a young age (Smith and Tasnadi, 2007)

• Lack of proper nourishment, such as not meeting RDA for F/V, affects health and hampers growth, can result in poor school performance (Whitaker et al., 2006)

• 17% of nation’s youth have BMI at or above recommended 95th percentile (NIH, 1998)

• Children from low income families are at higher risk!• Teachable moment: children consume food outside of the

home on a regular basis– Lunch – USDA sponsored food programs (low income)

MOTIVATION | FIELD EXPERIMENT | RESULTS | CONCLUSIONS & IMPLICATIONS


Role of Behavioral Approach

• Incentives can Motivate Behavior Change– Agents value even small incentives to shift health behavior – weight

loss, smoking cessation (Volpp et al., 2008; 2009)– Value of incentives for child food choice (Just and Price, 2011)

• Gain and Loss Framing– According to Kahneman and Tversky’s (1991) model of loss aversion,

incentives framed as losses are more effective than incentives framed as gains

• Long-term impact– Negative rebound effect (Lepper et al., 1973)– Habit formation (Gneezy et al., 2011)

• Educational Messages– Long-term, in-depth educational interventions have some effect– Simple verbal prompts have effect (Schwartz, 2007; Perry, 2004)



Field Experiment• Kids Cafe program – after school program in low-income

areas of Chicago, including suburbs– Majority of children in these areas eligible for the Free or

Reduced School Lunch Program– Sites are at schools, community centers, churches

• 1,616 separate participants ages 6 to 18 across 24 different sites – Kids visit daily, several times a week, or sporadically

• Two phases: February-March, 2011; April-May, 2011• Experimenters (3-6 per site) visited 2x per week and asked

children to choose between 1 cookie or 1 dried fruit cup



Meeting Daily Fruit Requirements

29%

71%

Child ate FruitChild Did Not Eat Fruit

Grain Vegetable Fruit Diary Protein0%

10%20%30%40%50%60%70%80%90%

100%

Food Group

Perc

enta

ge o

f Res

pond

ents


Daily Fruit Intake (24-Hour Recall)


On-Site Procedures• “Framed” field experiment in the sense that participants know they are in

an experiment (Harrison and List, 2004)• Choice is made after the “meal” is served and children have ID stickers on

• Experimenter reads the standard message– At least one of each is always available– Can only choose one– Cannot share it– Should eat it on site (can’t take it with)– Site can’t keep the remaining desserts to serve on other days

• Experimenter reads treatment-specific message (if any)• Experimenters record child’s ID, choice, and consumption



Field Experiment Design• Summary of Treatments


“Short” Study Session “Long Study Session”

Baseline X 116 participants

“Gain” Incentive Only 428 participants X

“Loss” Incentive Only 216 participants 107 participants

Education Only 141 participants 341 participants

“Loss” Incentive + Education

55 participants 170 participants

2x per week – 5 times totalB, T, B, B, B

2x per week – 9 times totalB, T, T, T, T, T, B, B, BChoice of Fruit

Cup or Cookie

Get a prize for eating Fruit

Educational message

Combination Treatment


Incentives – “Gain Frame”• If you choose the dried fruit cup, and eat all of it

today, you will also get to pick a gift immediately after you finish eating it! You can choose ONE of these gifts.



“Loss Frame”• “But before you choose a dessert, you should come up

and pick a gift. You can choose ONE of these gifts.”• “We’ll put the gift in a closed box for you with your

name on it, and you get to take it back to your table.”• “If you eat the fruit cup, we’ll open the box for you

and you will keep the gift you picked up.”• “If you don’t finish eating all of it, you will have to

give the box back to us and you will not keep the gift you picked…”



Short Education Message• Based on USDA Requirements• …the Food Pyramid…reminds us to make healthy food choices. Do

you notice that some of the stripes are wider than others? The different sizes remind you to choose foods from the widest stripes…

• Eating just one new, good thing everyday will make a big difference!• The fruits group has a pretty wide stripe…• What about cookies? Cookies aren’t on the pyramid…



Result Summary – “Short” SessionsMOTIVATION | FIELD EXPERIMENT | RESULTS | CONCLUSIONS & IMPLICATIONS

1-Baseline 2-Treated 3-Baseline 4-Baseline 5-Baseline0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

EducationEducation+LossLoss IncentiveGain IncentiveBaseline

Period and Day Type

Prop

ortio

n Ch

oosi

ng F

ruit


Result Summary – “Long” SessionsMOTIVATION | FIELD EXPERIMENT | RESULTS | CONCLUSIONS & IMPLICATIONS

1-Baseline 2-Treated 3-Treated 4-Treated 5-Treated 6-Treated 7-Baseline 8-Baseline 9-Baseline0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

EducationEducation+LossLoss IncentiveBaseline

Period and Day Type

Prop

ortio

n Ch

oosi

ng F

ruit


Period 1 versus Period 2• Comparing a “baseline” visit to a “treated”

visit• Compare both “between subject” and “within

subject” to test for treatment effects



Baseline and Treatment Comparison

• Result 1: Incentives significantly increase the proportion of children selecting fruit

Baseline Gain Incentive Loss Incentive Education Education + Loss Incentive

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Period 1Period 2

Treatment

Prop

ortio

n Ch

oosi

ng F

ruit



Comparing the Incentives• Result 2: The gain and loss treatment are equally effective

at moving children to choose the healthy option• Result 3: Education alone does not have a significant

effect, but education paired with incentive is more effective than education alone



Consumption• Direct link between choice of food to

consumption cannot be taken for granted• Example: Just et al. (2011) find that in the

lunchroom, over 44% of items taken by students are wasted

• We provide a link between selection and consumption

• We have detailed consumption data for 73% of choices on average – level of 1/4s



Proportion Consumed• Result 4: The loss treatments result in increased

consumption of fruit more than the gain incentive, but the education treatment results in a decreased consumption of fruit relative to baseline



Summary of Findings• Incentives are very effective in the short-term

(immediate) in increasing both fruit choice and consumption– Incentives provide a reduction in food waste

compared to education alone– Gain and loss frame incentives similar in value

• Incentives combined with education most effective– No ‘rebound’ effect; could be implemented at

relatively low cost in practice



White Milk vs. Chocolate• Utility-maximizing individual makes tradeoff between• Expected enjoyment of food eaten in the present• Expected future potential health consequences

• Present and future• Individuals generally discount the future• Health consequences take time to appear

• Facing uncertainty • May be unsure about taste (if haven’t tasted recently)• May be unsure about health benefits/consequences• Health consequences not tied directly to one

consumption


Summary of Treatments• Effect of different

prompts in the school lunch-line

• “healthy” – changes belief about future benefit

• “tasty” – changes belief about current benefit

• Incentive – changes current benefit directly



Stats

Number of Schools: 9Separate Kids: 2,200Milk Consumed: 690 gallonsTotal Trays Weighed: 19,000


K-3rd versus 4th-8th

Pre Base

line

50/50 M

ilkDay 1

Day 2Day 3

Day 4Day 5

50/50 M

ilk

Post Base

line

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Pre Base

line

50/50 M

ilkDay 1

Day 2Day 3

Day 4Day 5

50/50 M

ilk

Post Base

line

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Control Health PromptRegular Prompt Taste PromptIncentive


Summary of Preliminary Results

• All prompts significantly increase white milk choice in round 1

• Incentives more effective than prompts• Health and Taste prompts work for younger

children• Taste and Prompt, but not Health, works for

older children• Prompt effectiveness decreases over time (as

expected – children form greater beliefs)


Future Work• Effect of incentivizing parents vs. children to

improve child food choice

• Effect of coupons and pre-commitment at grocery stores in ‘food deserts’

• Changing the incentives in the ‘a la carte’ line


Thank you!

Anya C. [email protected]


Timeline of ImplementationMORE INFORMATION


Fruits and Cookies ServedMORE INFORMATION


Demographics & Food Security• Have data on 280 children across all sites• Food security, Child age• Low Income

66%

20%

14%

Household

This graph shoes the percentages of parents that fall into each food security category using the USDA measure for food se-curity and responses from the parent pre-survey.

Age Proportion4-8 33%9 to 13 56%14-18 11%

MOTIVATION | FIELD EXPERIMENT | RESULTS | CONCLUSIONS & IMPLICATIONS | RELATED WORK

the behavioralist as dietician: leveraging behavioral economics to improve child food choice and...

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