Zulily

read in data from file

zulilydata<-read.table("zulilycsv.csv", header = T, sep = ",")
names(zulilydata)

## [1] "Demand90"        "TotalNewMembers" "Variable"

summary(zulilydata)

##     Demand90   TotalNewMembers    Variable   
##  Min.   :100   Min.   : 5.0    Min.   :11.0  
##  1st Qu.:200   1st Qu.:10.0    1st Qu.:34.0  
##  Median :233   Median :11.0    Median :40.0  
##  Mean   :373   Mean   :29.4    Mean   :45.6  
##  3rd Qu.:333   3rd Qu.:22.0    3rd Qu.:44.0  
##  Max.   :999   Max.   :99.0    Max.   :99.0

Regression

demand<-lm(Demand90 ~ TotalNewMembers + Variable, data=zulilydata)
summary(demand)

## 
## Call:
## lm(formula = Demand90 ~ TotalNewMembers + Variable, data = zulilydata)
## 
## Residuals:
##        1        2        3        4        5 
## -90.6348  52.1467  36.4020  -0.5022   2.5883 
## 
## Coefficients:
##                 Estimate Std. Error t value Pr(>|t|)  
## (Intercept)     131.0020    74.0505   1.769   0.2189  
## TotalNewMembers   9.6676     1.9389   4.986   0.0379 *
## Variable         -0.9261     2.3527  -0.394   0.7319  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 78.31 on 2 degrees of freedom
## Multiple R-squared:  0.9763, Adjusted R-squared:  0.9526 
## F-statistic: 41.19 on 2 and 2 DF,  p-value: 0.0237

Check vif (install Car package) for whole regression

library(car)
vif(demand)

## TotalNewMembers        Variable 
##        3.806045        3.806045

check Durbin-Watson (install lmtest package)

library(lmtest)

## Loading required package: zoo

## 
## Attaching package: 'zoo'

## The following objects are masked from 'package:base':
## 
##     as.Date, as.Date.numeric

dwtest(demand)

## 
##  Durbin-Watson test
## 
## data:  demand
## DW = 1.7941, p-value = 0.3291
## alternative hypothesis: true autocorrelation is greater than 0