Hypotheses:
Ho: µ2001 = µ2000
Ha: µ2001 < µ2000
You will need to use a 2-sample formula for this type of test. You have all the data needed for both samples. This is a one-tailed test because the alternative hypothesis is showing a specific direction. If the null is rejected in favor of the alternative hypothesis, then there is a difference (in other words, µ2001 < µ2000).
According to a survey conducted in October 2001, consumers were trying to reduce their credit card debt (Extracted from M. Price, “Credit Debts Get Cut Down to Size." Newsday, November 25, 2001, p. F3). Based on a sample of 1000 consumers in October 2001 and in October 2000. the mean credit card debt was $2411 in October 2001as compared to $2814 in October 2000. Suppose that the sample standard deviation was $847.43 in October 2001 and $976.93 in October 2000. Assuming the population variances from both years are equal, is there evidence that the mean credit card debt was lower in October 2001 than in October 2000? (Use the 0.05 level of significance)
1 answer
1 answer