912 11732 1 no 3 365.55165430764 2 no

(a) Summarizethedatawithascatterplot between y and x1, usingseparatesymbolsforthe twocategoriesof x2.

(b) Fitthemodel E(Yi) = β0 + β1xi1 + β2xi2. Interprettheestimatedeffects.

(c) Reportandinterpret R2 for summarizingtheglobalpredictivepower.

(d) Conductasignificancetestfortheeffectofwhetherthehouseisnew,adjustingforsize.

Interpret.

(e) Atthemeansizeofthenewhomes,findandinterpreta95%confidenceintervalforthe mean sellingpriceofnewhomesanda95%predictionintervalforthesellingpriceofa new home.

(f)UsingCook’sdistance,identifythemostinfluentialobservationforthemodelfit.Analyze the effectoffittingthemodelwithoutit.(We’llseethatthisobservationisnotinfluential or evenunusualwhenweconsideranalternativemodelin Section 7.1.3 that allowsthe variabilityofsellingpricetoincreaseasitsmeanincreases.)