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A study reports: r (95) = +92, p = .01. How confident can you be that the obtain

ID: 3322063 • Letter: A

Question

A study reports: r(95) = +92, p = .01.  How confident can you be that the obtained correlation is real and not due to mere chance?

92% confident

95% confident

99% confident

There is not enough information to tell.

3 points   

QUESTION 18

When correlation is used for prediction purposes, a value of .50 is generally considered to be

small

medium

large

3 points   

QUESTION 19

If you recomputed the correlation on a sample twice as large as your original sample, what would happen to the tabled value of the correlation coefficient necessary for the obtained correlation to be considered "real?"

It would increase.

It would decrease.

It would remain the same.

There is no way to predict what would happen.

3 points   

QUESTION 20

If you square the correlation coefficient, you get

the true correlation value.

the common variance.

the sample size needed for statistical significance.

the causal portion of the correlation.

3 points   

QUESTION 21

The correlation between two variables is -.64.  How much common variance is there between these two variables?

-.41

+.41

-.80

+.80

3 points   

QUESTION 22

Under which one of the following conditions may a causal relationship between variables X and Y be inferred?

Whenever an investigation other than a correlation coefficient has shown them to be causally related.

Whenever the correlation coefficient is other than 0.

Whenever the correlation coefficient is positive.

Whenever the correlation coefficient is exactly +1.00 or -1.00.

92% confident

95% confident

99% confident

There is not enough information to tell.

Explanation / Answer

17) We are (100-1)% = 99% confident. (Ans).

18) A correlation value of 0.50 is considered as Medium. (Ans).

19) The correlation value should remain same since it is coming from same population. (Ans).

20) Squaring the correlation co-efficient will give the true value of correlation. (Ans).

21) Between the common variables there exist 80% common variance (Ans).

22) Correlation doesn't imply causal relationship. A causal relationship between two variables exist if an investigation other than a correlation co-efficient has shown them to be causally related. (Ans).