Exam 14: Regression Analysis

For questions below , use the following: A researcher selects a random sample of 8 high school students. Each student is tested on both Need Achievement and Mechanical Aptitude. The scores were: Subject Need Achievement Mechanical Aptitude 1 12 10 2 2 3 3 5 7 4 9 5 5 11 9 6 10 8 7 4 6 8 1 3 -Should Ho be rejected or accepted? And if rejected, state the significance level.

Use the following: Assume a significant XY correlation of .85 and a sample size of 30. The mean of X equals 800.00, and the mean of Y equals 20.00. The estimated sd of X equals 75.00, and the estimated sd of Y equals 3.70. -Find the .95 confidence interval for the predicted Y value.

Use the following: Assume a significant XY correlation of .60 and a sample size of 62. The mean of X equals 14.00, and the mean of Y equals 2.00. The estimated sd of the sample X equals 3.00 and the estimated sd of Y equals .80. -Calculate the standard error of estimate.

When the correlation between X and Y equals zero, then the slope of the regression line of Y on X is equal to

Find the .95 confidence interval for the predicted Y value.

For questions below , use the following: A researcher selects a random sample of 8 high school students. Each student is tested on both Need Achievement and Mechanical Aptitude. The scores were: Subject Need Achievement Mechanical Aptitude 1 12 10 2 2 3 3 5 7 4 9 5 5 11 9 6 10 8 7 4 6 8 1 3 -Find the .99 confidence interval for the predicted Y value.

The standard error of estimate may never equal zero, unless the Pearson r equals 1.00.

The standard error of estimate may never assume a value larger than the true standard deviation of the Y distribution.

Calculate the standard error of estimate.

The more the value of a Pearson r deviates from zero, the greater its predictive power.

The slope of the regression line of Y on X must always assume a positive value.

A corporate researcher runs Pearson r correlations among three variables, net income, gross income and amount spent on advertising. All correlations are significant. Net Income and Gross Income = .60 Net Income and Advertising = .53 Gross Income and Advertising = .35 Find the multiple R for predicting net income from both gross income and advertising. For questions 116 through 119, use the following: A researcher collects the following measures: Y mean = 50, with a standard deviation of 10 X1 mean = 100, with a standard deviation of 15 X2 mean = 200, with a standard deviation of 20 Significant correlations among the variables were found to be as follows: y and 1 = .60 y and 2 = .75 1 and 2 = .20

When information regarding two or more predictor variables is combined in order to predict performance on Y, then the appropriate statistical test is

When predicting from a three-factor, multiple R, the value of b indicates

For questions below, use the following: A researcher collects the following measures: Y mean = 50, with a standard deviation of 10 X1 mean = 100, with a standard deviation of 15 X2 mean = 200, with a standard deviation of 20 Significant correlations among the variables were found to be as follows: y and 1 = .60 y and 2 = .75 1 and 2 = .20 -Find the .99 confidence interval for the predicted Y score.

For the Pearson r, the degrees of freedom are a direct function of the number of pairs of scores.

Find the .99 confidence interval for the predicted Y value.

For questions below, use the following: A group of 8 elementary school students was randomly selected . Each pupil was tested on both Math Ability and Spelling Ability. Their scores were: Subject Math Test Spelling Test 1 14 15 2 12 10 3 3 2 4 9 10 5 8 7 6 5 6 7 10 9 8 2 4 -Should Ho be rejected ? If rejected, state the significance level.

For questions below, use the following: A group of 8 elementary school students was randomly selected . Each pupil was tested on both Math Ability and Spelling Ability. Their scores were: Subject Math Test Spelling Test 1 14 15 2 12 10 3 3 2 4 9 10 5 8 7 6 5 6 7 10 9 8 2 4 -Find the standard error of estimate.

For questions below, use the following: A group of 8 elementary school students was randomly selected . Each pupil was tested on both Math Ability and Spelling Ability. Their scores were: Subject Math Test Spelling Test 1 14 15 2 12 10 3 3 2 4 9 10 5 8 7 6 5 6 7 10 9 8 2 4 -Find the Pearson r correlation between the Math and Spelling scores.