*I'll be reviewing a*

**New York State Regents Exam**Question every day from now until the Regents exams begin next month. At least, that is the plan.### August 2014, Questions 31

**31.** *
The table below represents the residuals for a line of best fit.
Plot these residuals on the set of axes below.
Using the plot, assess the fit of the line for these residuals and justify your answer.
*

Plot the points on the table. It should look like this:

If a regression line is a "good fit", the residuals should be scattered about, above and below the x-axis, randomly.

If a pattern emerges, then the regression is not a good fit for the data. (For example, suppose you did a linear regression, but the data suggested that you should have done a quadratic regression instead. Then a pattern will emerge in the residuals.)

The graph below shows that there is a pattern among the residuals, and it looks like it forms a curve.
**DO NOT** draw the curve! Just explain that it is not a good fit because of the pattern.

Any questions?

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