Exam 15: Correlation and Regression

Based on the summary data below, predict the Extroversion (Y) scores for people who scored 10, 15, and 20 on Happiness (X). (Hint: you will need to calculate the slope and Y-intercept to use in the regression equation. r = .77 M_x = 18.87 s_x = 2.75 M_y = 7.25 s_y = 2.12

A correlation of r = .69 is found between scores on a biology test and scores on a chemistry test. What is the coefficient of determination?

Calculate r for the following set of scores:

A sleep researcher is interested in the relationship sleep and memory. A random sample of 7 participants is selected for the study. Scores on the number of hours slept (X) and the number of memory errors (Y) are shown below. Conduct a nondirectional Pearson correlation test with α = .01.

A negative correlation coefficient suggests that

If overlapping circles are used to illustrate the relationship between the coefficients of determination and nondetermination, the area of non-overlap represents

If an assessment designed to measure introversion is given to the same people two weeks apart and their scores are similar on both occasions, ______________ has been demonstrated.

Which of the following statements reflects a positive correlation?

If r = .64, what is the coefficient of nondetermination?

Write the null and alternative hypotheses in symbolic form for a nondirectional Pearson correlation test.

If a college admissions officer uses SAT scores to predict college GPA, college GPA is the ___________ variable.

If overlapping circles are used to illustrate the relationship between the coefficients of determination and nondetermination, the area of overlap represents

If there are ten questions about analytical geometry on your biology test, the test shows a lack of _____________.

A negative correlation is also called a(n) ________________ relationship.

It is called __________________ when a sample is used that limits the scores on one or more variables more so than would be found in the population.

Write the null and alternative hypotheses in symbolic form for a negative Pearson correlation.

_______________ is used to predict the value of a score on one variable by knowing the score on the other.

Indicate whether the correlations below would most likely be positive or negative. a. Ice cream sales and outside temperature. b. Number of days without rain and length of grass. c. Age and agility. d. Amount of coffee consumed and level of alertness.

If a college admissions officer uses high school GPA to predict college GPA, high school GPA is the ___________ variable.

Which term or phrase below best describes correlation research?