Q1) Can people really recognize their favourite brand of cola? Volunteers tasted Diet Pepsi, Coca-Cola Classic, Pepsi, Diet Coke, and with results given below.
Research question: At α = .05, is correctness of the prediction different for 2 kinds of cola drinkers?
Could you identify your favourite brand in this kind of test?
As it is a 2 × 2 table, try also two-tailed two-sample z test for π1 = π2 and verify that z2 is same as your chi-square statistic. Which test do you prefer? Explain why?
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Correct
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Regular Cola
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Diet Cola
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Row total
|
|
Yes, got it right
|
7
|
7
|
14
|
|
No, got it wrong
|
12
|
20
|
32
|
|
column total
|
19
|
27
|
46
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