7) +1 & -1 represent perfect liner relationship between x and y. Because whenever correlation values are nearby +1 & -1, then there is strong correlation
8) population correlation - p( Greek Rho)
Sample correlation - r
Question 7 1 pts Which of the correlation values represent a perfect linear relationship between x...
1. Match the correlation coefficient to its variable.
Population Correlation (choose below)
a. c
b. p (Greek rho)
c. r
d.R
c. Greek alpha
Sample Correlation (choose below)
a. c
b. p (Greek rho)
c. r
d.R
c. Greek alpha
Question 7 1 pts Which of the correlation values represent a perfect linear relationship between x and y? 0-1 O1 0.05 100
Let r be the correlation coefficient. Denote the explanatory variable by X and the responsible variable by Y . Which statement is correct ? (A) Positive r indicates a perfect linear relationship between X and Y . (B) r is always a number between 0 and 1. (C) r is almost 0 if values of X’s and Y ’s are all positive. (D) The correlation of variables −X and Y is −r. (E) None of the above.
pts Compute the linear correlation coefficient between the two variables and determine whether a linear relationship exists. х 1 8 -1 18 5 2 y 13 1 3 10 4 8 11 6 3 0 15 2 Or=-0.995; linear relation exists O r=-0.885; no linear relation exists O r=-0.995; no linear relationship exists O r=-0.885; linear relation exists Question 30 4 pts The table lists the drinking habits of a group of college students. If a student is chosen at...
7. You are testing the null hypothesis that there is no linear relationship between two variables, X and Y. From your sample of n=18, you determine that b1=4.4 and Sb1=1.7. a. What is the value of tSTAT? b. At the α=0.05 level of significance, what are the critical values? c. Based on your answers to (a) and (b), what statistical decision should you make? d. Construct a 95% confidence interval estimate of the population slope, β1. 8. You are testing...
(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...
Question 4 1 pts Suppose a experiment is conducted to study the relationship between the percentage of a certain drug in the bloodstream (X) and the length of the time it takes to react to a stimulus (Y). The results are below. X 2 1 4 3 5 Y 1 1 2 2 4 z = 15, Ey=10, 22 = 55, y = 26, ry= 37. Find the coefficient of correlation between x and y. 0 -0.85 O 0.85 O...
1. When no linear relationship exists between variable X and variable Y, r equals which of the following? a) −∞-∞ b) -1 c) 0 d) +1 e) +∞+∞ 2. Pearson’s r correlation measures the relationship between which of the following? a) Two continuous variables b) Two categorical variables c) One continuous and one categorical variable
Question 7 (Unit 9) 10 marks Figure 2 shows a scatterplot of r and y values for each of 100 data points in a sample 2 2 3 X Figure 2 The correlation coefficient associated with Figure 2 is claimed to be -0.9. (a) Is the value claimed for the correlation coefficient plausible in terms of its sign? Justify your answer [2] (b) Is the value claimed for the correlation coefficient plausible in terms of its closeness to -1? Justify...
Incorrect Question 6 0/1 pts If the direct linear relationship between x and y is given by equation yw a+b'x. The inverse linear relationship is given by the equation x + C + d'y, where is equal to... a/b -1/2 1/ -alb -1/b
Question 29 4 pts Compute the linear correlation coefficient between the two variables and determine whether a linear relationship exists. $ 4 X- 11 8 V 18 131 6 7 3 2 10 11 6 60 3 2 15 OP= -0.995;linear relation exists Ors.0.885; no linear relation exists O r.0.995. no linear relationship exists OP=-0.885: linear relation exists Question 30 4 pts The table lists the drinking habits of a group of college students. If a student is chosen at...