ONE – SAMPLE SIGN TEST
CASE ANALYSIS -1
A survey is conducted with 20 respondents to test the hypothesis that the median value of the time spent in a mall is 130 minutes against the hypothesis that it is more than 130 minutes. The time spent by the students is as follows.
Table-1: Sample Data
The hypotheses for the analysis are:
Null hypothesis-H0: The median value is 130 m.
Alternative Hypothesis- H1: The median value is greater 130m. (One tailed test)
Performing the Analysis with SPSS
For SPSS Version 11, click on Analyze ⇒ Non parametric tests ⇒ Binomial
This will bring up the following SPSS screen dialogue box.
After clicking Binomial, this will bring up the following SPSS dialogue box.
Select the variable and move it to the Test Variable(s) list box.
Fill the cut point as 130 and finally click OK to get the output
The SPSS output are illustrated uin following tables.
Table-2: Binomial Test
Reject the null hypothesis if p-value (Sig. (2-tailed)) ≤ 0.05
The p-value for one-tailed test would be Sig. (2-tailed)/2.
The p-value is (0.115)/2= 0.0575 and it is more than 0.05 (5% level of significance), so we accept the null hypothesis and reject the alternative hypothesis. The median value of the time spent in a mall is more than 130 minutes.
- Click on ANALYZE at the SPSS menu bar (in older versions of SPSS, click on STATISTICS instead of ANALYZE.
- Click on NON-PARAMETRIC TEST followed by 2 RELATED SAMPLES.
- Select the concerned variables and move THEM TO TEST PAIR(S) LIST box.
- Click SIGN.
- Click OK of the main dialogue box