In the Joumal of Marketing Research (November 1996), Gupta studied the extent to
ID: 2907536 • Letter: I
Question
In the Joumal of Marketing Research (November 1996), Gupta studied the extent to which the purchase behavior of scanner panels is representative of overall brand preferences. A scanner panel is a sample of households whose purchase data are recorded when a magnetic identification card is presented at a store checkout. The table below gives peanut butter purchase data collected by the A. C. Nielson Company using a panel of 2,500 households in Sioux Falls, South Dakota. The data were collected over 102 weeks. The table also gives the market shares obtained by recording al peanut butter purchases at the same stores during the same period Number of Purchases by Household Panel 3,162 1,801 758 4,021 6,223 1.646 Shares 19.96% 8.46 4.32 16.19 25.07 12.28 13.72 Jif 8 oz. 28 40 Peter Pan 10 Skippy 28 40 Total 19,087 (0-EYE 110.138 21.480 5.373 280.377 432.075 207.793 498.655 1,555.891 %ofchisq 7.08 1.38 35 18.02 27.77 13.36 obs 3,162 3,809.765 1,614.760 824.558 4,021 3,090.185 4,785.111 1,646 2,343.884 618.736 19,087 19,086.999 647.765 188.240 66.558 30.815 1,437,889 697.884 1,801 758 6,223 001 100.01 (a) Show that it is appropriate to carry out a chi-square test. Each expected value is 2 (b) Test to determine whether the purchase behavior of the panel of 2,500 houscholds is consistent with the purchase behavior of the population of all peanut butter purchasers. Assume here that purchase decisions by panel members are reasonably independent, and set a - .05. (Round your answersx to 2 decimal places and x2.05 to 3 decimal places.) (Click to select) A Ho. Conclude purchase behavior is Click to select)Explanation / Answer
each expected value is >=5
from abvoe output: X2 =1555.89
and for (categories-1=6) degree of freedom and 0.05 level X2 0.05 =12.592
reject Ho; conclude puchase behavior is not consistent