a. 1

b. 0.5

c. -0.5

d. 0

1) If the correlation coefficient between two random variables X and Y is 0.3, then the correlation coefficient between (2X+3)/5 and (4Y+7)/11 is?

a. 0.3

b. 0.3/(11*5)

c. (2*4*0.3)/(11*5)

d. None of the above.

- Thread starter harshalishah
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a. 1

b. 0.5

c. -0.5

d. 0

1) If the correlation coefficient between two random variables X and Y is 0.3, then the correlation coefficient between (2X+3)/5 and (4Y+7)/11 is?

a. 0.3

b. 0.3/(11*5)

c. (2*4*0.3)/(11*5)

d. None of the above.

So the answers would be:

1. c?

2. a?

C is the correct answer for 1 but B is the correct answer for 2.

Is it A or B for the second question?

Well, the coefficient is determined by the strength and the direction of the linear relationship between two variables. If there is a linear negative relationship between two variables, the coefficient is between 0 and -1. If there is a linear positive relationship between two variables, the coefficient is between 0 and 1. The stronger the relationship, the closer is the coefficient to -1 or 1.

But given that the correlation between two variables x and y is, say, 0.3, we know that the absolute size of the correlation between x and y won't change if x and/or y are linearly transformed. However, the sign will flip if we multiply x or y by -1.

But given that the correlation between two variables x and y is, say, 0.3, we know that the absolute size of the correlation between x and y won't change if x and/or y are linearly transformed. However, the sign will flip if we multiply x or y by -1.

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But given that the correlation between two variables x and y is, say, 0.3, we know that the absolute size of the correlation between x and y won't change if x and/or y are linearly transformed. However, the sign will flip if we multiply x or y by -1.

So the correlation won't change even if the numbers are divided by a positive number? (I'm talking about question 2 in this case.)