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 psychologistâs findings is that immediately after the workshop, a sample of 49 job seekers who received training on resume writing 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.
(a) The psychologist finds that the estimated Cohenâs d is .
(b) The t statistic is 4.12, and r² is .

The answers to the question are;

(a) The psychologist finds that the estimated Cohen's d is __0.562.

(b) The t statistic is 4.12, and r² is ___ 7.322 × 10⁻² .

Step-by-step explanation:

To solve the question, we note the given variables as follows

Sample count N = 49

Mean of sample statistics = = 6.5

Mean of population = μ = 5.8

Sample standard deviation, s = 1.2

The t statistic is given as

t = = 4.08

(a) The Cohen's D is used as an indication of the effect of the size or magnitude of an object.

d is given as

d = =  

Where:

M₁ = Group 1 mean = 6.5

M₂ = Group 2 mean = 5.8

=  

Where:

s₁ = Standard deviation of group 1 sample = 1.2

s₂ = Standard deviation of group 2 sample

Since the statistics is pooled we can take s₁² = s₂²

Therefore  = = = s₁

Therefore

d = =   = = 0.583

However since N < 50 we make use of the correction factor as follows.

Correction Factor =

Therefore,

d =   ×  =  × =   ×0.964 = 0.562

Cohen's d = 0.562.

and

(b) To convert d into the coefficient of correlation, r, we have

r = =   = 0.271

r² =  0.07322 or 7.322 × 10⁻².

(-1,-0.5)

step-by-step explanation: