Questions from Statistics Principles

Q: Refer to the physical fitness data in the Data Bank. Find

Refer to the physical fitness data in the Data Bank. Find a 95% confidence interval for the mean difference of the pretest minus posttest number of sit-ups. Also test that the mean difference is zero...

Q: Refer to the Data Bank. The responses, of persons in

Refer to the Data Bank. The responses, of persons in the first and second age groups, on the frequency of credit card use question, have the summary statistics (a) Obtain a 98% confidence interval for...

Q: Two versions of a new simplified tax form, A1 and A2

Two versions of a new simplified tax form, A1 and A2, need to be evaluated with respect to the time, in hours, it takes to complete the form. Forty persons were selected to fill out Form A1 and 40 wer...

Q: The responses, of persons in the first and third age groups

The responses, of persons in the first and third age groups to the average monthly amount charged, have the summary statistics Determine a 95% confidence interval for the difference of means.

Q: On a day, the noon temperature measurements (in °F

On a day, the noon temperature measurements (in °F) reported by five weather stations in a st ate were 74 80 76 76 73 (a) Find the mean and median temperature in °F. (b) The Celsius (0 C) scale...

Q: Refer to the data in Exercise 10.53. Suppose you

Refer to the data in Exercise 10.53. Suppose you wish to establish that the mean response of 35-44 year old is larger than that of 19- 24 year old by more than 150 dollars. (a) Formulate the null hypo...

Q: A study of postoperative pain relief is conducted to determine if drug

A study of postoperative pain relief is conducted to determine if drug A has a significantly longer duration of pain relief than drug B. Observations of the hours of pain relief are recorded for 55 pa...

Q: Consider the data of Exercise 10.55. (a

Consider the data of Exercise 10.55. (a) Construct a 90% confidence interval for µA - µB. (b) Give a 95% confidence interval for µA using the data of drug A alon...

Q: Obtain s2pooled for the gaming data.

Obtain s2pooled for the gaming data.

Q: Given the following two samples, 6 9 3 3 7

Given the following two samples, 6 9 3 3 7 8 and 4 2 3 3 obtain (a) s2pooled and (b) the value of the t statistic for testing H0 : µ1 - µ2 = 1. State the d.f. of the t.