Identifying Programmer Ability Using Peer Evaluation: An Exploratory Study

Jeffrey C. Carver, University of AlabamaLorin Hochstein, USC Information Sciences Institute

Jason Oslin, University of Alabama

The Importance of Categorizing Programmer

Ability

• In Industry

• In Research

• In Teaching

2

How We Measure Ability

• Professional vs. Novice

• Years of Experience

• Elaborate Evaluations

3

Is There A Better Way?

• Peer evaluation

• “We know a good programmer when we see one”

• Subjective judgment as a predictor

4

Outline

• Study Design

• Data Analysis

• Conclusions

• Future Work

5

Our Study

• Goal– Characterize peer assessment of

programmer ability from the point of view of a researcher in the context of an undergraduate computer science course

• Hypotheses–H1: Developers are able to accurately

predict the programming ability of their peers

–H2: Low-performers tend to over-estimate their ability

6

Test Environment

Senior Level Programming Languages Course

– Five individual assignments

– Graded by the unbiased instructor

– Student participation had no effect on grade

7

Data Collected

• Subjective Data– Participant evaluation of self– Participant evaluation of peers– Post-study questionnaire

• Objective Data– Grades on projects– “True” measure for this study

8

Collecting Subjective Data

9

Sample data collection form

Coding the Grades

10

• A = 5 Top 20%• B = 4• C = 3• D = 2• E = 1 Bottom 20%

Coding the Grades

11

A Look at the Data Set

12

Raters

Ratees

A Look at the Data Set

13

Evaluating Hypothesis 1Developers are able to accurately predict

the programming ability of their peers

14

Act

ual

Gra

de

Mode Of Peer Ratings

Additional Observation

15

Actual Grade

Diff

ere

nce

Betw

een

Mod

e a

nd

Act

ual

Evaluating Hypothesis 2Low-performers tend to over-estimate their

ability

16

Actual Grade

Self Rating

A Qualitative Analysis

• Rating oneself

• Compare my self perception to my peers’ perception of my ability

• Confidence in rating peers

17

Threats to Validity

• Construct– Are grades a valid indicator of ‘true’

ability?– Ceiling effect displayed by skew of grades?– Are we evaluating enough skill sets

involved in software development?

• Low number of ratings• What happens when we move beyond

from classrooms to industry?

18

Future and Ongoing Work

• Running the study again

• Goals of future work– Characterize high-performers–Understand programming ability– Improve competent programmers

19