Which of the following are true statements about the correlation coefficient r? I. A correlation coefficient of .3 means that 30% of the points are highly correlated. II. The square of the correlation measures the proportion of the y-variance that is predictable from a knowledge of x. III. Perfect correlation, that is, when the points lie exactly on a straight line is r = 0.
The only true statement among the given ones is:
II. The square of the correlation measures the proportion of the y-variance that is predictable from a knowledge of x.
Which of the following are true statements about the correlation coefficient r? I. A correlation coefficient...
Determine whether each of the following statements regarding the correlation coefficient is true or false. The correlation coefficient equals the proportion of times that two variables lie on a straight line. The correlation coefficient will be +1.0 if all the data points lie on a perfectly horizontal straight line. The correlation coefficient measures the strength of any relationship that may be present between two variables. The correlation coefficient must always lie between –1.0 and +1.0.
Which of the following statements regarding the correlation coefficient is not true? A) The correlation coefficient has values that range from-1.0 to 1.0 inclusive. B) The correlation coefficient measures the strength of the linear relationship between two numerical variables C) A value of 0.00 indicates that two variables are perfectly linearly correlated D) All of these are true statements
Which of the following statements about the correlation, r, between Y and X is NOT true? A. r measures the strength of the linear association between Y and X. B. r does not provide any information about the strength of non-linear relationships. C. r = 0 means there is no relationship between Y and X. D. Calculating r is not appropriate if the distributions of Y and X are skewed with outliers.
If a researcher obtained an r of -0.85, what could you say about this correlation? - This is a strong negative correlation. O This is a strong positive correlation. O This is a weak negative correlation. O This is a weak positive correlation. Question 4 1 pts If a researcher wanted to see if cumulative GPA predicts GRE scores, which of the two variables would be the predictor variable? The number of participants None of the other answers O GRE...
Select the answer that correctly identifies how many of the following statements are true for a simple linear regression model. I) It has one independent and one dependent variable. II) It describes a straight line relationship between the two variables. III) It has no error term. IV) The slope parameter and the correlation coefficient will have the same sign. A Only one of the statements is true. B Exactly two of the statements are true. C Exactly three of the...
A covariance coefficient is bounded between 1 and -1. True or False? A correlation of 1.0 means that a scatterplot of X and Y would result in all the values falling on a straight, downward sloping line. True or False?
14. Multiple Choice Variables x and y have a correlation coefficient of r = 0.89. Which statement is best? a. There is a strong positive association between x and y and a straight line fit to the data cannot be substantially improved by fitting a curve to the data. b. There is a strong positive association between x and y and a straight line fit to the data can certainly be substantially improved by fitting a curve to the data....
(8 points) Match the following sample correlation coefficients with the explanation of what that correlation coefficient means. Type the correct letter in each box. 1. r = -.15 2. r = 0 3. r = 1 4. r = -97 A. a strong negative relationship between x and y B. no relationship between x andy C. a weak negative relationship between x and y D. a perfect positive relationship between x and y Note: You can earn partial credit on...
1. Which is not true of R², the coefficient of determination ? a It is the square of the coefficient of correlation. b. It is calculated using sums of squares (e.g., SSR, SSE, SST). c. It reports the percent of the variation in Y explained by X. d. It is negative when there is an inverse relationship between X and Y.
TRUE or FALSE: Identify which of the following are valid statements and which ones are false. i. T F A ear odel is fit to a data set exhibiting a linear relationship. One of the data points is an outlier with respect to r, ie. its r-value is umisual compared to all other r-values but its y-value falls within the observed range of Y. Removing this data point likely change the estimated sample slope by a considerable amount ii. T...