Purchase Solution

Correlation questions

Not what you're looking for?

Ask Custom Question

1. For the following scores,

X Y
3 6
6 1
3 4
3 3
5 1

a) Find the regression equation for predicting Y from X
b) Calculate the predicted Y value for each X
2. For the following scores

X Y
1 6
4 1
1 4
1 3
3 1

a) Compute the Pearson correlation

3. Identifying individuals with a high risk of Alzheimer's disease usually involves a long series of cognitive tests. However, researcher have developed a 7-Minute Scree, which is a quick and easy way to accomplish the same goal. The question is whether the 7-Minute Screen is as effective as the complete series of tests. To address this question, Ijuin et al. (2008) administered both tests to a group of patients and compared the results. The following data represent results similar to those obtained in the study.

Patient 7-Minute Screen Cognitive Series
A 3 11
B 8 19
C 10 22
D 8 20
E 4 14
F 7 13
G 4 9
H 5 20
I 14 25

a) Compute the Pearson correlation to measure the degree of relationship between the two scores.
b) Is the correlation statistically significant? Use a two-tailed test with an alpha=.01
c) What percentage of variance for the cognitive scores is predicted from the 7-Minute Screen scores? (Compute the value of r2 )

Attachments
Purchase this Solution

Solution Summary

The solution provides detailed explanation how to find the correlation coefficient and figure out the regression equation.

Purchase this Solution


Free BrainMass Quizzes
Measures of Central Tendency

This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.

Know Your Statistical Concepts

Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.

Measures of Central Tendency

Tests knowledge of the three main measures of central tendency, including some simple calculation questions.

Terms and Definitions for Statistics

This quiz covers basic terms and definitions of statistics.