More brains Refer to Exercise 20

a. Explain why it isn’t correct to say that the correlation is 0.86g/kg

b. What would happen to the correlation if the variables were reversed on the scatterplot?

Explain your reasoning.

c. What would happen to the correlation if brain weight was measured in kilograms instead of grams? Explain your reasoning.

Short Answer

Expert verified

Part (a) This statement is not true.

Part (b) The correlation remains the same.

Part (c) The correlation will remain the same.

Step by step solution

01

Part (a) Step 1: Given information

02

Part (a) Step 2: Explanation

We must determine why it is incorrect to state that the correlation is0.86g/kgin order to answer this question. As a result, we can't state the correlation is 0.86g/kg because the units "g/kg" were allocated to the correlation. Correlation, on the other hand, is never related with units. As a result, this statement is false.

03

Part (b) Step 1: Explanation

According to the question, we must determine what would happen to the correlation if the variables on the scatterplot were reversed. The correlation, as we all know, evaluates the degree of linearity between two variables. As a result, if the variables on the scatterplot are flipped, the amount of linearity between the two variables is unaltered, and the correlation is unaffected as well.

04

Part (c) Step 1: Explanation

We must determine what would happen to the association if brain weight was measured in kilogrammes rather than grammes, as stated in the question. The correlation, as we all know, evaluates the degree of linearity between two variables. As a result, measuring brain weight in kilogrammes rather than grammes has no effect on the link between the variables since the relationship remains the same. As a result, the level of linearity in the relationship between the variables remains unchanged, and the correlation remains unchanged.

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