Question

You no longer believe that the population standard deviation in the tuition amounts for this population is a known quantity. You therefore will use the standard deviation in the tuition amounts of a representative sample of universities as an estimate of the unknown population standard deviation. You collect yearly tuition data from a random sample of universities once again. This data is shown in appendix one below. Once again, at each of the 5% and 10% levels of significance, is the mean yearly tuition less than $20,000? Again, in your memo, comment upon the effect of the change in the level of significance on your decision, if necessary. Also, compare, at each level of significance, the results of this portion of the problem to those of the previous part. Account for any difference in your decisions at each level of significance between the two parts of the problem. Make this accounting based not only on a mathematical approach, but rather on a conceptual justification.

            Appendix One: (Tuition Amounts)

            $22,000          $25,412          $18,543          $21,010          $32,500

            $13,476          $18,765          $17,689          $12,378          $21,800

            $19,548          $22,348          $17,659          $18,654          $23,409

            $31,329          $14,489          $15,698          $11,389          $19,901

            $25,671          $18,888          $14,490          $24,468          $15,690

            $13,298          $30,000          $12,390          $21,672          $20,037

            $21,876          $19,090          $21,684          $24,347          $18,000

            $12,769          $17,032          $26,876          $18,923          $15,119

            $15,632          $20,000          $21,769          $15,858          $13,607

            $24,879          $17,540          $14,027          $13,908          $12,690

Please provide an explanation of your answer!

Answer 1