In: Statistics and Probability
A researcher has conducted a survey for Danone yogurt to understand what type of customers buy its products. Thus, in the survey, each respondent is asked if he is a Blue or White collar employee (that is if the respondents has an office job or not) and whether he buys the company’s yogurt or not. The results are shown in the following cross-tabulation table. Danone Yogurt Buyer Nonbuyer Total White Collar 152 8 160 Blue Collar 14 26 40 Total 166 34 200
Danone Yogurt |
|||
Buyer |
Nonbuyer |
Total |
|
White Collar |
152 |
8 |
160 |
Blue Collar |
14 |
26 |
40 |
Total |
166 |
34 |
200 |
a.) Using the table and your calculations, give a clear example of a cross-tabulation cell, column total, row total, grand total, observed frequency cell, expected frequency cell. (2 points)
b.) What is the maximum Chi-Square value you must have, for you to say that there is a statistically significant relationship between the two variables, with 95% accuracy? (1 point)
c.) Is there any relationship between the two variables, type of responder and buyer type? (3 points)
d.) What is the managerial insight you derive from this analysis? (2 points)
Chi-Square Test of independence | |||||||
Observed Frequencies | |||||||
0 | |||||||
0 | B | N | Total | ||||
WC | 152 | 8 | 160 | ||||
BC | 14 | 26 | 40 | ||||
Total | 166 | 34 | 200 | ||||
Expected frequency of a cell = sum of row*sum of column / total sum | |||||||
Expected Frequencies | |||||||
B | N | Total | |||||
WC | 166*160/200=132.8 | 34*160/200=27.2 | 160 | ||||
BC | 166*40/200=33.2 | 34*40/200=6.8 | 40 | ||||
Total | 166 | 34 | 200 | ||||
(fo-fe)^2/fe | |||||||
WC | 2.776 | 13.553 | |||||
BC | 11.104 | 54.212 | |||||
B)
Chi-Square Test Statistic,χ² = Σ(fo-fe)^2/fe = | 81.644 |
Level of Significance = 0.05
Number of Rows = 2
Number of Columns = 2
Degrees of Freedom=(#row - 1)(#column -1) = (2- 1 ) * ( 2- 1 )
= 1
p-Value = 0.0000 [Excel function:
=CHISQ.DIST.RT(χ²,df) ]
Decision: p-value < α , Reject Ho
C)
YES, there is a relationship between the two variables, type of responder and buyer type
D)
Sale of danone yougurt depends upon whether the employee is white or blue collar.