Share
Explore BrainMass

# Yules coefficient and interpretation

7. There is a program for STD/HIV/pregnancy education/prevention called Postponing Sexual Involvement (PSI) run in Atlanta. Evaluation data collected at the end of ninth grade as a follow-up to the program compared two group of adolescents - one treatment and one control - all of whom had not had sex at the pretest (beginning of eighth grade). My reconstruction of the appropriate data table is below.
(5 points).
Sex at end of ninth grade?
Yes No
PSI 61 195 256
Comparison 43 66 109
104 261 365

Using tabi and/or hand calculations, compute the following measures and then present an interpretation of the results to answer the following simple question: Did the program have an effect in the expected direction?
Difference between proportions of having sex:________________
Odds Ratio of Sex/No Sex in the PSI versus the Comparison:__________
Yule's Q:__________________________

So, did the program have an effect in the expected direction?

EXPLAIN YOUR CONCLUSION:

#### Solution Preview

Please see the attached file.

Let (A) denote number people who had PSI program
Let (B) denote number of people who said no to sex
Let (α) denote number of people who had not PSI program
Let (β) denote number of people who said yes to sex ...

#### Solution Summary

Calculation of Yules coefficient and its interpretation. It uses data from program for Postponing Sexual Involvement (PSI).

\$2.19