A sample of n200 obituaries is elected from the newspaper an

A sample of n=200 obituaries is elected from the newspaper and old school records are consulted to determine the individuals IQ scores when they were between the ages of 10 and 20. The individuals were then classified into two IQ groups and three age groups at the time of of death. The data is as follows, Based on these results, employ a statistical test and provide advice whether a significant relationship between IQ and longevity exists. in your answer show all hand and excel calculations, test at alpha 0.05 a. State the null hypotheses b. State the design requirements and assumptions c. State the decision rule d. Calculate the value of the of the tests statistic and make a decision e. State the conclusion f. Calculate and interpret effect size if appropriate

Age at the time of death
                   >60        60 to 75          > 75
IQ<110         41         63                      36

IQ_>110          9           27                    24
     

Solution

Set up null and alternate hypotheses as:

H0: Longevity does not depend on IQ

Ha: Longevity does depend on IQ.

Two tailed chi square test

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The chi-square statistic is 6.2857. The p-value is .043159. The result is significant at p < .05.

Conclusion is IQ and longevity are dependent.