Statistics case

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Regression Analysis

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Sheet1Weeks on the MarketSelling Price1Weeks on the MarketSelling Price23$243,270Coefficient of variation52.15%Coefficient of variation21.30%48$324,360Mean28.9365079365Mean272582.9047619059$168,540Standard Error1.9011507842Standard Error7313.834661976726$267,756Median26Median26775620$232,140Mode32Mode19080040$397,500Standard Deviation15.0899165391Standard Deviation58051.762937503251$346,620Sample Variance227.7055811572Sample Variance3370007180.1520818$190,800Kurtosis1.7963691261Kurtosis0.110433273125$276,660Skewness1.3718794746Skewness0.754780574862$298,920Range69Range25440033$241,680Minimum9Minimum16854011$286,200Maximum78Maximum42294015$193,980Sum1823Sum1717272326$273,480Count63Count6327$222,60056$422,94012$295,7402[PLACE YOUR DIAGRAM FOR PART 2 HERE]29$270,02960$373,01411$198,03433$281,14425$235,62250$417,18864$381,28223$190,80031$329,22578$333,86641$326,26814$317,68219$211,43832$290,70934$311,64070$359,49915$298,69712$375,00024$340,00020$310,000[TYPE YOUR EXPLANATION FOR PART 2 HERE] This would be a good data set for simple linear regression because there appears to ba a positive relationship between the Weeks on the Market and Selling Price. That is as Weeks on the Market increases so to does the Selling Price.28$279,90032$278,50028$273,00012$272,00020$270,00012$270,0003SUMMARY OUTPUT32$258,50028$255,000Regression Statistics24$253,0001- and +1Multiple R0.612885399624$249,000closer to 1 is betterR Square0.37562851332$245,000Adjusted R Square0.365392914928$244,000Standard Error46245.328773413932$241,000Observations6324$239,50028$238,000ANOVA32$236,500dfSSMSFSignificance F20$235,000Regression178483988734.398978483988734.398936.69824739710.000000093428$235,000Residual61130456456435.032138630433.3611424$233,000Total62208940445169.42932$230,00012$229,000CoefficientsStandard Errort StatP-valueLower 95%Upper 95%Lower 95.0%Upper 95.0%24$224,500Intercept204356.26692061512680.235761684316.11612518580179000.568662474229711.965178757179000.568662474229711.96517875716$220,000Weeks on the Market2357.8048184318389.2110743076.05790783990.00000009341579.52918189543136.08045496821579.52918189543136.080454968216$213,0000.000000093420$212,00028$204,000RESIDUAL OUTPUTObservationPredicted Selling PriceResidualsif p value is greater than alpha then value not good.1258585.777744548-15315.77774454752317530.8982053436829.10179465673225576.510286502-57036.51028650194265659.1921998432096.8078001575251512.363289252-19372.3632892526298668.45965788998831.54034211147324604.31266063922015.68733936128246796.753652388-55996.75365238839263301.38738141113358.612618588810350540.165663389-51620.165663388911282163.825928866-40483.825928865812230292.11992336655907.880076634513239723.339197093-45743.339197092914265659.1921998437820.80780015715268016.997018275-45416.997018274916336393.33675279886546.663247202117232649.92474179763090.075258202618272732.606655138-2703.606655138519345824.55602652527189.443973474820230292.119923366-32258.119923365521282163.825928866-1019.825928865822263301.387381411-27679.387381411223322246.50784220794941.492157793124355255.77530025326026.224699747425258585.777744548-67785.777744547526277448.21629200251776.783707997927388265.042758298-54399.042758298228301026.2644763225241.735523679529237365.53437866180316.46562133930249154.55847082-37716.558470820231279806.02111043410902.97888956632284521.63074729827118.369252702333369402.604210844-9903.604210843634239723.33919709358973.660802907135232649.924741797142350.07525820336260943.58256297979056.417437020737251512.36328925258487.63671074838270374.8018367079525.198163293439279806.021110434-1306.02111043440270374.8018367072625.198163293441232649.92474179739350.075258202642251512.36328925218487.63671074843232649.92474179737350.075258202644279806.021110434-21306.02111043445270374.801836707-15374.801836706646260943.582562979-7943.582562979347260943.582562979-11943.582562979348279806.021110434-34806.02111043449270374.801836707-26374.801836706650279806.021110434-38806.02111043451260943.582562979-21443.582562979352270374.801836707-32374.801836706653279806.021110434-43306.02111043454251512.363289252-16512.36328925255270374.801836707-35374.801836706656260943.582562979-27943.582562979357279806.021110434-49806.02111043458232649.924741797-3649.924741797459260943.582562979-36443.582562979360242081.144015525-22081.144015524761242081.144015525-29081.144015524762251512.363289252-39512.36328925263270374.801836707-66374.80183670664[TYPE YOUR ANSWER TO PART 4 HERE] (Compare p-value with alpha.) Based on an analysis of the p-value of 0.0000000933948 (9.33948E-08), we can see that the regression model is significant at the 1% level of significance. The relationship between the Weeks on the Market and Selling Price is significant at the 1% level of significance. Based on an analysis of the residual plot, the 4 assumptions that were about the regression model's error term appear to be valid. The regression model for the "Weeks on the Market" and "Selling Price" is = 204356.2669 + 2357.8048x. Based on this sample data regression model, 37.56% of the variability in the "Selling Price" can be explained by the "Weeks on the Market". Based on the regression analysis above there appears to be a moderately strong positive relationship between "Weeks on the Market" and "Selling Price". This is evidenced by a strength of relationship measure of 0.6129.= 204356.2669 + 2357.8048x291595.0452025935[TYPE YOUR ANSWER TO PART 5 HERE] = 204356.2669 + 2357.8048*37 = 291595.0452. Based on the current regression model if a condo were on the market for 37 weeks, they could expect it to sell for $291595.0452.

Sheet1

Selling PriceWeeks on the MarketWeeks on the Market vs. Selling Price

Compatibility Report

Weeks on the MarketResidualsWeeks on the Market Residual Plot

Compatibility Report for FALL-2011-Case12.xlsRun on 11/16/2011 16:40The following features in this workbook are not supported by earlier versions of Excel. These features may be lost or degraded when you save this workbook in an earlier file format.Minor loss of fidelity# of occurrencesSome cells or styles in this workbook contain formatting that is not supported by the selected file format. These formats will be converted to the closest format available.1