Question

Eighteen middle-aged women with platelet readings between 120,000 platelets per microliter and 150,000 platelets per microliter of blood were selected randomly from the population of similar female patients at a large local hospital. Nine of the 18 women were assigned randomly to group A and received a placebo. The other nine women were assigned to group B and received a new platelet drug. After four months, posttreatment platelet readings were taken for all 18 women and were compared with pretreatment readings. The reduction in platelet level (Pretreatment reading − Posttreatment reading) for each woman in the study is shown here.

Group A (placebo) increase (in platelets per microliter): 2,000, 5,000, 7,050, 10,125, 12,345, 17,350, 13,250, 12,200, 9,125

Group B (platelet drug) increase (platelets per microliter): 28,450, 23,438, 36,380, 12,450, 16,100, 21,350, 39,400, 41,000, 14,325

Part A: Do the data provide convincing evidence, at the α = 0.05 level, that the platelet drug is effective in producing a reduction in mean platelet level? (6 points)

Part B: Create and interpret a 95% confidence interval for the difference in the placebo and the new drug. (4 points)

Answer 1

Answer:-

Given that:-

Eighteen middle-aged women with platelet readings between 120,000 platelets per microliter and 150,000 platelets per microliter of blood were selected randomly from the population of similar female patients at a large local hospital. Nine of the 18 women were assigned randomly to group A and received a placebo. The other nine women were assigned to group B and received a new platelet drug. After four months, posttreatment platelet readings were taken for all 18 women and were compared with pretreatment readings. The reduction in platelet level (Pretreatment reading − Posttreatment reading) for each woman in the study is shown here.

Group A (placebo) increase (in platelets per microliter): 2,000, 5,000, 7,050, 10,125, 12,345, 17,350, 13,250, 12,200, 9,125

Group B (platelet drug) increase (platelets per microliter): 28,450, 23,438, 36,380, 12,450, 16,100, 21,350, 39,400, 41,000, 14,325

Here from the samples

       

There is no.difference in placebo & plates drug

The platelet drug is effecticve.

  

Test statistic

  

Critical value at 5% L.O.S is -1.746

P-value =0.05, Given

Here P-value<0.05, so reject

Hence there is a sufficient evidence that the platelet drug is effective.

B) At 95% confidence for 16 d.f

The 95% confidence intervals are