Exam 14: Regression Analysis

When the slope of the regression line equals -3.00, then

If the slope value equals +10, then Y increases by 10 units for each equal unit increase in X.

When the slope of the regression line of Y on X is positive, then the array of data points on the scatter plot

If X is independent of Y, the safest Y pred., given information about X, is the mean of the Y distribution.

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 -Predict the Y value for a known X1 value of 115 and a known X2 value of 220.

The partial correlation may never be used, unless more than two variables are involved.

For questions below, use the following: A random sample of college students was selected from the population of male, physical-education majors. The mean height was 68". The mean weight was 150 lbs. The mean waist-measure size was 32". The standard deviations were, for height, 3" for weight, 30 lbs for waist-size, 2" Significant Pearson r's were, Height and weight, .70 Height and waist-size, .40 Weight and waist-size, .30 -Find the .95 confidence interval for the predicted Y value.

The Pearson r between variables y and 1 is a significant .73. The Pearson r between variables y and 2 is a significant .62. Find the multiple R for predicting y from 1 and 2.

The Pearson r correlation between variables y and 1 is a significant .60. The Pearson r correlation between variables y and 2 is a significant .50. The Pearson r between variables 1 and 2 is a significant .70. Find the multiple R for predicting y from 1 and 2.

For questions below, use the following: A random sample of college students was selected from the population of male, physical-education majors. The mean height was 68". The mean weight was 150 lbs. The mean waist-measure size was 32". The standard deviations were, for height, 3" for weight, 30 lbs for waist-size, 2" Significant Pearson r's were, Height and weight, .70 Height and waist-size, .40 Weight and waist-size, .30 -Find the multiple R for predicting height from both weight and waist-size.

The slope of the regression line is designated as the

A researcher runs Pearson r correlations among three variables, Grade- Point Average, IQ and Reading Speed. All correlations are significant. GPA and IQ = .80 GPA and Reading Speed = .85 IQ and Reading Speed = .60 Find the multiple R for predicting Grade-Point average from IQ and Reading Speed.

Find the multiple R for predicting y from the X1 and X2 variables.

The technique employed for establishing the correlation that is left over between two variables, when both are known to be correlated with a third variable, is called the

When the correlation in the sample is negative, it can never be used to extrapolate to the population.

In a two-variable scatter plot, the variable being predicted is placed on

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 -Predict a Y value for a known X value of 8.00.

A first-order partial correlation assesses the strength of the relationship between two variables, with the effects of a third variables held constant.

The regression line of Y on X must always slope from lower left to upper right.

The Pearson r, the multiple R, and the coefficient of determination all demand at least interval data.