Please show your reasoning You have two suppliers of plastics that are used to m
ID: 3208249 • Letter: P
Question
Please show your reasoning
You have two suppliers of plastics that are used to make a product. As far as you can tell with in-house testing the plastic each supply is the same. However, you are concerned that one of them may cause more customer product returns. The only data you can really use is whether or not a customer returns the part. What type of statistical test could you use to look for differences between the customer return rate? 2-sample t-test 2 proportions test Chi-square test paired t-testExplanation / Answer
Two proportions test would be the best option to test whether return rate is higher in one of the two plastics. Proportions test is used to test the differences between proportions under two INDEPENDENT populations. Hypothesis testing will be as follows:
Null Hypothesis: H0 : proportion of returns in first plastic is same as in the second plastic ie. p1 = p2
Alternative Hypothesis: Ha : proportion of returns in first plastic is higher than that in second plastic p1 > p2
This will be a one-tailed test.Statistic value will be calculated using the sample rate returns form each of two plastic samples, it will be compared with critical value from Normal Tables, and hence conclusion will be made comparing the above two. If statistic value is higher than critical value and we lie in the rejection region, then we can conclude that customer return rate in first plastic than that in the second. ANSWER
TY!