A Study of Preferences Under Constraint

Jayson Shi JiaKunal Patel

Research Question Will the existence of a consumption

constraint result in higher consumption at some point?

How does the modification of a consumption constraint change an agent’s consumption pattern?

Inspired by the “Yale College Law School Run” - of yore

Expect loss aversion and information effect with budget constraints

Why use an experiment? Can try to solve different FOC’s and

Lagrangians for different constraints Hard to conjecture what people will do

because we are interested in a behavioral effect

Needed at least a survey instrument Used the experiment and Excel to try some

other things, like looking at information effects Harder for subjects to ‘screw up’ when we

design things on excel as opposed to pencil and paper

Loss Aversion in Riskless Choice: A Reference Dependence Model (1991)

Reference Dependence

Gains and losses relative to reference level

Loss Aversion Losses loom larger than

gains Diminishing

Sensitivity The marginal value of

both gains and losses decreases with their size

Losses

Value

GainsReferencePoint

x-x

V(x)

V(-x)

Mental Accounting (Thaler 1985, 1990, 1999)

Framing: How a person subjectively frames a transaction in their mind will determine the utility they receive/expect

Expenditures grouped into a number of non-fungible accounts

Frequency with which accounts are evaluated and ‘choice bracketing’

What we initially wanted… Scenario 0: buffet – tell people to ‘eat’ as much as

they would normally like– don’t tell people how much they paid – see how much they would like to consume – use this to calculate x

Scenario 1: buffet where people are told they paid $x

Scenario 2: impose a constraint on consumption at $x, for which you pay $x

Scenario 3: pay $x for a constraint y, where y<x Scenario 4: pay $x for a constraint z, where z>x

Try to capture effects of loss aversion: scenario 0 is reference point, scenario 3 is loss, scenario 4 is gain

Menu Experiment (1)

Choose Items on a Menu (too easy?)

In each question, you have essentially solved a maximization problem and told us what amount of food maximizes your utility

Menu Experiment (2)

Gain and Loss treatments Control: all you can eat with no price -

measure natural reference point Give new reference points with new

budget constraints: Buffet, Buffet with market value price

tags, +$2 budget, +$4 budget, -10% budget, -20% budget

Menu Experiment (3)

Information treatment Reveal Percentage spending of others

– people see how efficient others are Reveal Absolute spending – people

realize base values are very different

Results – Part 1

Scenario Consumption ($)

Consumption relative to price/ budget (%)

Ideal World 12.80 n/a

Buffet - No Price 21.73 1.82

Buffet - Price 22.35 1.85

Retail x+$0 12.65 0.99

Retail x+$2 14.55 0.99

Retail x+$4 16.65 0.99

Retail x-10% 9.93 0.97

Retail x-20% 7.45 0.97

Results – Part 2Total Consumption ($)

ScenarioSituation 2: Revealed Percentage Spending

Situation 3: Revealed Absolute Spending

Retail x+$0 12.70 12.72

Retail x+$2 14.67 14.68

Retail x+$4 16.47 16.47

Retail x-10% 10.02 9.98

Retail x-20% 7.45 7.42

Criticism Small sample size (trading games didn’t

have this problem because bids were individual data points) – not much we can say now

Experiment design: diversity seeking bias with a big menu

Overly involved sample population – sabotage, trying to open hidden pages, too much talking, context and group effects

Future Improvements Larger sample size to allow for

statistical analysis Focus on one commodity, e.g. cell

phone minutes, emission credits Ask people to rate satisfaction for

different gains and losses – this is to measure the value function

No PhD students in sample

Thanks for listening!