Serum ferritin is used in diagnosing iron deficiency. In a study conducted recently researchers discovered that in a sample of 28 elderly men the sample standard deviation of serum ferritin was 52.6 mg/L. For 26 younger men the sample standard deviation was 84.2 mg/L. At the .01 level of significance, do these data support the conclusion that the ferritin distribution in elderly men has a smaller variance than in younger men?
A. No, because the test value 1.60 is less than the critical value of 2.54
B. Yes, because the test value 2.56 is greater than the critical value of 2.54
C. Yes, because the test value 0.390 is less than the critical value 2.54
D. Yes, because the test value 2.56 is greater than the critical value 0.394
The solution provides step by step method for the calculation of independent sample t test. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.