Hypothesis Testing Problem Set Essay

SE = 2.1820749866

Hypothesis Testing

Answer each question completely to recieve full credit

There is a new drug that is used to treat leukemia. The following data represents the remission time in weeks for a random sample of 21 patients using the drug.

State the Null Hypothesis

Let XA represent the mean remission time of the new drug and XB the mean remission time of the previous drug, then the null hypothesis states that the eukemia remission times are not significantly different (Ho: XA = XB) between the two drugs.

State the Alternatice Hypothesis

The alternative hypothesis is that the time to remission is significantly different (H1: XA ? XB) between the two drugs.

State the Level of significance

= .01, two-tailed

State the Test Statistic

Z scores

Perform Calculations

Since ? = .01 and this is a two-tailed test, then the value for each tail would be .005.This corresponds to a Zcrit value of ±2.58.

XA = 17.095; SDA = 10.000; Std. Error (SEA) = 10/?21 = 2.182

Z = (XB - XA)/SEA = (12.5-17.095)/2.182 = -2.11

The probability of getting a Z score of -2.11 is p = .0174, or a Z score of ±2.11 is p = .0348, two-tailed.

Statistical Conclusion

Siince Zcrit > Z, then the null hypothesis cannot be rejected. This conclusion is also supported by the fact that approximately 1.7% of patients using the new drug would be expected to have a remission time equal to or less than the mean remission time obtained using the previous drug.

Experimental Conclusion

At the confidence level selected for this comparison, the mean remission times between the two drugs are not.....