Nutrition 209a  Final Exam: Data Analysis Portion    Fall 2001

            You are to analyze the two data sets described in this 
        memo.  You may refer to books, journals, and your notes, but 
        ALL HUMAN ASSISTANCE IS FORBIDDEN.  You may not discuss any 
        aspect of these problems with your classmates.  

            Each answer should take up no more that a single side of a 
        sheet of paper.  You may, in addition, attach the computer 
        printout upon which you base your conclusions.  However, do 
        *not* include output that is irrelevant to your final report. 

            Do not place your name on your answers.  Instead, you will 
        mark them with the random number that you choose at the in-
        class portion of the exam on Monday, 2-4, at Posner Lecture 
        Hall.


                      (1)  Calcium formulations

            A vitamin company is trying to decide which of two 
        formulations (TYPE$) of calcium to market.  Forty subjects are 
        enrolled into a study (20 subjects on each formulation) to see 
        if one produces higher mean calcium levels.  Baseline values 
        are collected, but the samples are spoiled in transit to the 
        lab that will analyze them.  Since it is a randomized double 
        blind, controlled trial, the decision is made to base the 
        decision on the subjects' 6 month calcium levels (CA) which 
        are contained in the file CASUPP.SAV.  What do you recommend? 
        Justify your recommendation. 


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                         (2)  Insects and Crop Yield

            There's this country and this crop and this insect.  And 
        because no one's ever studied it, someone wonders whether the 
        insect affects crop yield.  Might it help fertilize the plant?  
        Might it interfere with crop growth?  So, about 150 acres of 
        farmland are selected at random from all over the country.  
        The dataset INSECT.SAV contains the yield per acre and number 
        of insects per acre.  Is crop yield related to insect 
        concentration?  Estimate the yield from an acre where there 
        are 50 insects.  Justify your answer.