# Regression

Submitted By kaoxiaojie
Words 1577
Pages 7
1) | Sales | TV | Radio | Fuel.Volume | 1 | Min. :18969 | Min. : 0.00 | Min. : 0.00 | Min. :56259 | 2 | 1st Qu.:21171 | 1st Qu.: 0.00 | 1st Qu.: 0.00 | 1st Qu.:61754 | 3 | Median :22924 | Median : 0.00 | Median : 0.00 | Median :63136 | 4 | Mean :23064 | Mean : 41.28 | Mean : 80.47 | Mean :62853 | 5 | 3rd Qu.:24489 | 3rd Qu.: 70.00 | 3rd Qu.:205.00 | 3rd Qu.:64637 | 6 | Max. :28451 | Max. :225.00 | Max. :260.00 | Max. :68549 |

2) a) Yes, The p-value is 9.72e^-12. Much lower than Tyler’s 10% significant level. | Value | Prediction | Lower | Upper | 1 | Minimum | 18809.35 | 14777.04 | 22841.66 | 2 | Mean | 23063.73 | 19182.71 | 26944.74 | 3 | Max | 26739.02 | 22744.55 | 30733.49 | b)

c) See above d) Greater fuel volumes could translate as greater number of customers. With greater numbers visiting the gas station, there is a greater chance the customer will visit the store.
3)

Residuals: Min 1Q Median 3Q Max
-4955.8 -1750.4 -232.4 1464.2 4730.6

Coefficients: Estimate Std. Error t value Pr(>|t|)
(Intercept) 22142.385 275.018 80.513 < 2e-16 ***
TV 12.193 3.874 3.147 0.00219 **
Radio 5.195 2.700 1.924 0.05726 .
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

Residual standard error: 2138 on 98 degrees of freedom
Multiple R-squared: 0.2544, Adjusted R-squared: 0.2391
F-statistic: 16.72 on 2 and 98 DF, p-value: 5.673e-07

a) Yes, they both fall under Tyler’s 10% level of significance.

Value | Prediction | Lower | Upper | TV=40, Radio =80 | 23045.72 | 18782.89 | 27308.54 |

| tv | radio | Amount | 300 |…...

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