Question

In excell

• t-Test Assuming Equal Variances
• t-Test With Paired Two Samples for Means
• Analysis of Variance
• Correlation Coefficient
• Simple Regression

Skills and self-esteem are believed to influence job performance. To investigate this, an experimenter split 14 recent parolees into "high skill and self-esteem" and "low skill and self-esteem" groups. Three months later, employers were asked to rate each parolee’s job performance on a standard test that gives ratings from 1 to 10, with 10 being the highest. The following ratings were obtained for the individuals in the two groups:

High skills and self-esteem	Low skills and self-esteem
9	6
6	5
3	5
8	4
7	4
7	5
9	6

a. Run descriptive statistics on the data. Please provide measures of central tendency and variability for the entire sample and also by groups.

b. Are there differences in job performance between the two groups? In your response, provide the answers to the following:

(i) The test you will run.

(ii) The null and research hypothesis.

(iii) The test results (copy the results to the word doc).

(iv) Your interpretation of the results.

Answer 1

1. Run descriptive statistics on the data. Please provide measures of central tendency and variability for the entire sample and also by groups.

High skills and self-esteem		Low skills and self-esteem	full data
Mean	7	5	6
Standard Error	0.786795792	0.3086067	0.491689172
Median	7	5	6
Mode	9	5	6
Standard Deviation	2.081665999	0.816496581	1.839732422
Sample Variance	4.333333333	0.666666667	3.384615385
Kurtosis	1.807100592	-1.2	-0.678812923
Skewness	-1.24160907	0	0.259425078
Range	6	2	6
Minimum	3	4	3
Maximum	9	6	9
Sum	49	35	84
Count	7	7	14

b. Are there differences in job performance between the two groups? In your response, provide the answers to the following:

(i) The test you will run.

In excel, t-Test Assuming Equal Variances used

(ii) The null and research hypothesis.

(iii) The test results (copy the results to the word doc).

t-Test: Two-Sample Assuming Equal Variances
	High skills and self-esteem	Low skills and self-esteem
Mean	7	5
Variance	4.333333333	0.666666667
Observations	7	7
Pooled Variance	2.5
Hypothesized Mean Difference	0
df	12
t Stat	2.366431913
P(T<=t) one-tail	0.017816008
t Critical one-tail	1.782287556
P(T<=t) two-tail	0.035632017
t Critical two-tail	2.17881283

(iv) Your interpretation of the results.

Calculated t=2.3664, P=0.0356 which is < 0.05 level of significance. Ho is rejected.

There is enough evidence to conclude that there is differences in job performance between the two groups.