a) Does there appear to be a positive, negative, or no relationship? How can you

Question

a) Does there appear to be a positive, negative, or no relationship? How can you tell?

b) Is there any evidence of a non-linear relationship? Why or why not, and what effect will this have on the correlation coefficient (in other words, why does this matter)?

c) Is there any evidence of issues such as heteroscedasticity or outliers? Why or why not, and what effect will they likely have if they're there?

d) Roughly, what range would you expect r2 to be in? Why? (You should explain what r2 is on at least your first answer).

e) Given all of your answers above, how accurate would you expect to be in predicting future ? scores based on X (i.e., would you expect the Standard Error of Estimation to be high, low, or moderate)? If you have said that there is no relationship, what would the Standard Error of Estimation be equal to (don't need to calculate a value here - recall that there is an upper limit to the SEoE).

Explanation / Answer

a.the scatter plot indicates no relationship among variables as the points are randomly and almost symmetrically distributed on both side of the center line..

b.no theere is no Evidence of a non linear relationship.as the plot indicates no linear trend and plots are completely random

c.The doesn't indicate any heteroscedasticity or outlier as there is no single point which lies very fary from the rest..if there is an outlier it will more likely to increase (or decrease in case of negetive outliers) the mean and the variance.

d.As described in 1st answer there is no lineae dependence of y on x which readily implies correlation coefficient r² is very low more likely to be <0.2 or 0.25.

e.A prediction based on the above data will not be a good one as there is no functional relationship among y and x but due to absence of outliers and the data is randomly allocated the standard error should be moderate...

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