Question

Consider the following data drawn independently from normally distributed populations: (You may find it useful to reference the appropriate table: z table or t table) *1 = -28.3 s12 = 8.7 ni = 22 X2 = -18.5 s 2 = 7.9 n2 = 16 a. Construct the 95% confidence interval for the difference between the population means. Assume the population variances are unknown but equal. (Round all intermediate calculations to at least 4 decimal places and final answers to 2 decimal places.) Confidence interval is to

Answer 1

The statistical software output for this problem is :

Two sample I summary confidence interval: Hi : Mean of Population 1 H2 : Mean of Population 2 Hi-L2 : Difference between two means (with pooled variances) 95% confidence interval results: Difference Sample Diff. Std. Err. DF L. Limit U. Limit Hi - 2 -9.8 0.95037871 36 -11.727457 -7.8725426

The 95% CI is : -11.73 to -7.87