An employee of a university’s recreational facility is interested in the effect of exercise in maintaining mental ability. She decides to study the faculty members aged 40 to 50 at her university, looking separately at two groups: the ones that exercise regularly, and the ones that don't. There are many people in each group, so she takes a simple random sample of 120 people from each group for detailed study, with the samples taken independently of each other.

 One of the things she does is to give an IQ test to everyone in the study. Those who exercise regularly have an average IQ of 135, with an SD of 15, and those who don’t exercise regularly have an average IQ of 125, with an SD of 20.

 (a) Carry out all the steps of a two-sample z test to evaluate the null hypothesis that these two populations have the same average IQ. (b) Suppose we wanted to use the results of this study to conclude that exercise does indeed help to maintain mental ability. What is the problem with this?

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question
An employee of a university’s recreational facility is interested in the effect of exercise in maintaining mental ability. She decides to study the faculty members aged 40 to 50 at her university, looking separately at two groups: the ones that exercise regularly, and the ones that don't. There are many people in each group, so she takes a simple random sample of 120 people from each group for detailed study, with the samples taken independently of each other.

 One of the things she does is to give an IQ test to everyone in the study. Those who exercise regularly have an average IQ of 135, with an SD of 15, and those who don’t exercise regularly have an average IQ of 125, with an SD of 20.

 (a) Carry out all the steps of a two-sample z test to evaluate the null hypothesis that these two populations have the same average IQ. (b) Suppose we wanted to use the results of this study to conclude that exercise does indeed help to maintain mental ability. What is the problem with this?
Expert Solution
steps

Step by step

Solved in 4 steps with 1 images

Blurred answer
Similar questions
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman