Peer Effects on GPAPeer Effects on GPA

Robyn Meikle and Joyce SilverRobyn Meikle and Joyce Silver

Difficulties Measuring Peer Effects

Difficulties Measuring Peer Effects

Self-selection bias Determining causal direction Is outcome due to peer effect or preexisting

characteristics?

Self-selection bias Determining causal direction Is outcome due to peer effect or preexisting

characteristics?

Overcoming Self-SelectionOvercoming Self-Selection

Using randomly generated roommate sample at Dartmouth College

Scardote proved this by regressing various background characteristics and proving no correlation among roommates

Using randomly generated roommate sample at Dartmouth College

Scardote proved this by regressing various background characteristics and proving no correlation among roommates

Dummy VariablesDummy Variables

Used to distinguish outcomes based on subject background from outcomes generated by a peer effect

Pre-treatment groups around academic index (high school grades): top 25%, middle 50% or bottom 25%

Used to distinguish outcomes based on subject background from outcomes generated by a peer effect

Pre-treatment groups around academic index (high school grades): top 25%, middle 50% or bottom 25%

Multiple RegressionMultiple Regression

Used to verify causal direction of peer effect

Regression 1: subject GPA-roommate GPA Regression 2: subject GPA-roommate

background Outcome variable (GPA) is determined by

subject background, roommate background and roommate GPA.

Used to verify causal direction of peer effect

Regression 1: subject GPA-roommate GPA Regression 2: subject GPA-roommate

background Outcome variable (GPA) is determined by

subject background, roommate background and roommate GPA.

ConclusionsConclusions

Why this happens Choice architecture Nurture over Nature?

Policy Implications Education policy

Questions?

Why this happens Choice architecture Nurture over Nature?

Policy Implications Education policy

Questions?