$11\mathrm{.}68$ Project: This project can be done in groups

or as individuals. Each group or person must find a set

of data, preferably but not restricted to their field of

study. The data need to fit the regression framework

with a regression variable $x$ and a response variable $y.$

Carefully make the assignment as to which variable is $x$

and which $y.$ It may be necessary to consult a journal

or periodical from your field if you do not have other

research data available.

$($a$)$ Plot $y$ versus $x.$ Comment on the relationship as

seen from the plot.

$($b$)$ Fit an appropriate regression model from the data.

Use simple linear regression or fit a polynomial

model to the data. Comment on measures of qual$-$

ity.

$($c$)$ Plot residuals as illustrated in the text. Check pos$-$

sible violation of assumptions. Show graphically

a plot of confidence intervals on a mean response

plotted against $x.$ Comment.