Question

Employers often use standardized measures to gauge how likely it is that a new employee with little to no experience will suceed in thier company. One such factor is intelligence, measured using the intelligence quotient (IQ). To show that this factor is related to job success, an organizational pychologist measures the IQ score and job performance (i units sold per day) in a sample of 10 new employees

IQ Job performance

100 17

115 35

108 24

98 16

120 42

147 55

132 46

85 54

105 25

110 36

(a) convert the following data to ranks and then compute a spearman correlaion coefficient (round your answer to three decimal places)

(b) using a two-tailed test at a 0.05 level of significance, state the decision to reject or retain the null hypothesis

Answer 1

IQ	Job performance			x-y=
x	y	x rank	y rank	d	d2
100	17	8	9	-1	1
115	35	4	6	-2	4
108	24	6	8	-2	4
98	16	9	10	-1	1
120	42	3	4	-1	1
147	55	1	1	0	0
132	46	2	3	-1	1
85	54	10	2	8	64
105	25	7	7	0	0
110	36	5	5	0	0
				∑d2	76

Spearman correlation coefficient =

rs=1-6Σd2/(n(n2-1))=

0.539

b)

for 0.05 level with two tailed test & n=10 , critical value =

0.6480

since test statistic is not higher than critical value ,  retain the null hypothesis