An industrial/organizational psychologist has been consulting with a company that runs weekend job-seeking workshops for the unemployed. She collected data on several issues related to these workshops and, after conducting statistical tests, obtained statistically significant findings. She needs to find a way to evaluate effect size so that she can make recommendations to the company.One of the psychologist's findings is that six months after the workshop, a sample of 49 job seekers who received training on using the Internet to find job listings scored an average of 6.5 as measured on a 9-point job-search satisfaction scale, with a standard deviation of 1.2. The typical job seeker scores 5.8 points.

The psychologist finds that the estimated Cohen's d is , the t statistic is 4.12, and r is .

Using Cohen's d and Cohen's guidelines for interpreting the effect size with the estimated Cohen's d, there is a treatment effect. Using r and the extension of Cohen's guidelines for interpreting the effect size using r, there is a treatment effect. (Hint: When using Cohen's guidelines for interpreting the effect size, if the value lies between two categories, then specify the range covered by both categories, for example, medium to large.)

Another one of the psychologist's findings is that a sample of 144 job seekers who received training on interview skills worked more than 30 hours an average of 6.9 months in the last year, with a standard deviation of 2.5. The typical job seeker works 6.4 months.

She finds that the estimated Cohen's d is , the t statistic is 2.38, and r is . Using Cohen's d and Cohen's guidelines for interpreting the effect size with the estimated Cohen's d, there is a treatment effect. Using r and the extension of Cohen's guidelines for interpreting the effect size with r, there is a treatment effect.