Question

Please run a two sample test on independent means using the given data. You may use either a calculator or statdisk but please indicate clearly at the top of your word document what method you are using. if you can type everything out it would be helpful sometimes its hard to read some handwritings but PLEASE STATE THE METHOD YOUR USING EITHER STATDISK OR A CACULATOR

Is Job Satisfaction going down? In the past ten years, several authors have stated that people are miserable in their jobs and have become increasingly unhappy over time. Job satisfaction scores from participants in the General Social Survey (GSS) in 1975 and 2006 were studied. Higher scores indicate greater satisfaction, with 2.5 being a neutral score. Here are summaries of scores for 1975 and 2006:

Year	Sample Size	Mean	Sample Std Dev
1975	1165	3.37	0.81
2006	2177	3.32	0.80

a) Run a test of significance to see if there is a significant decrease in mean scores from 1975 to 2006? Be sure to clearly state the null and alternative hypotheses, clearly label and state the value of the test statistic, clearly label and state the value of the P-value and clearly state the conclusion of the test in the context of the problem.

b) The paper from which the data came includes several years from 1972 to 2006. 1975 was the year with the highest mean score. What, if any, effect does this information have on your assessment of whether job satisfaction has decreased over time?

Answer 1

a) (1) Null and Alternative Hypothesis:

H0: there is not significant decrease in mean scores from 1975 to 2006

H1: there is a significant decrease in mean scores from 1975 to 2006

i.e.

Thus we conclude that  there is a significant decrease in mean scores from 1975 to 2006

b) Yes  this information effect have on your assessment of whether job satisfaction has decreased over time