Using R, read the data into a data frame called store. Play close attention to Exhibit 3 - Summary Statistics from Sample Stores from the CASE. Using R, get the summary statistics of the data. Confirm that the summary statistics generated from R are consistent with Exhibit 3 from the Case.
stores.df<- read.csv("Store24.csv")
#summary(stores.df)
library(psych)
describe(stores.df[,2:11])[,c(1:4,8,9)]
## vars n mean sd min max
## Sales 1 75 1205413.12 304531.31 699306.00 2113089.00
## Profit 2 75 276313.61 89404.08 122180.00 518998.00
## MTenure 3 75 45.30 57.67 0.00 277.99
## CTenure 4 75 13.93 17.70 0.89 114.15
## Pop 5 75 9825.59 5911.67 1046.00 26519.00
## Comp 6 75 3.79 1.31 1.65 11.13
## Visibility 7 75 3.08 0.75 2.00 5.00
## PedCount 8 75 2.96 0.99 1.00 5.00
## Res 9 75 0.96 0.20 0.00 1.00
## Hours24 10 75 0.84 0.37 0.00 1.00
4 D1 Use R to measure the mean and standard deviation of Profit.
mean(stores.df$Profit)
## [1] 276313.6
sd(stores.df$Profit)
## [1] 89404.08
4D2-Use R to measure the mean and standard deviation of MTenure.
mean(stores.df$MTenure)
## [1] 45.29644
sd(stores.df$MTenure)
## [1] 57.67155
4D3-Use R to measure the mean and standard deviation of CTenure.
mean(stores.df$CTenure)
## [1] 13.9315
sd(stores.df$CTenure)
## [1] 17.69752
Sorting and Subsetting data in R
attach(mtcars)
View(mtcars)
newdata <- mtcars[order(mpg),]
View(newdata)
newdata[1:5,] # 1 out of first 5 rows
## mpg cyl disp hp drat wt qsec vs am gear carb
## Cadillac Fleetwood 10.4 8 472 205 2.93 5.250 17.98 0 0 3 4
## Lincoln Continental 10.4 8 460 215 3.00 5.424 17.82 0 0 3 4
## Camaro Z28 13.3 8 350 245 3.73 3.840 15.41 0 0 3 4
## Duster 360 14.3 8 360 245 3.21 3.570 15.84 0 0 3 4
## Chrysler Imperial 14.7 8 440 230 3.23 5.345 17.42 0 0 3 4
4 F1Use R to print the {StoreID, Sales, Profit, MTenure, CTenure} of the top 10 most profitable stores.
attach(stores.df)
newdata <- stores.df[order(-Profit),]
View(newdata)
newdata[1:10,c("store","Sales","Profit","MTenure","CTenure")]
## store Sales Profit MTenure CTenure
## 74 74 1782957 518998 171.09720 29.519510
## 7 7 1809256 476355 62.53080 7.326488
## 9 9 2113089 474725 108.99350 6.061602
## 6 6 1703140 469050 149.93590 11.351130
## 44 44 1807740 439781 182.23640 114.151900
## 2 2 1619874 424007 86.22219 6.636550
## 45 45 1602362 410149 47.64565 9.166325
## 18 18 1704826 394039 239.96980 33.774130
## 11 11 1583446 389886 44.81977 2.036961
## 47 47 1665657 387853 12.84790 6.636550
4 F2-Use R to print the {StoreID, Sales, Profit, MTenure, CTenure} of the bottom 10 least profitable stores.
attach(stores.df)
## The following objects are masked from stores.df (pos = 3):
##
## Comp, CrewSkill, CTenure, Hours24, MgrSkill, MTenure,
## PedCount, Pop, Profit, Res, Sales, ServQual, store, Visibility
newdata <- stores.df[order(Profit),]
View(newdata)
newdata[10:1,c("store","Sales","Profit","MTenure","CTenure")]
## store Sales Profit MTenure CTenure
## 37 37 1202917 187765 23.1985000 1.347023
## 61 61 716589 177046 21.8184200 13.305950
## 52 52 1073008 169201 24.1185600 3.416838
## 54 54 811190 159792 6.6703910 3.876797
## 13 13 857843 152513 0.6571813 1.577002
## 32 32 828918 149033 36.0792600 6.636550
## 55 55 925744 147672 6.6703910 18.365500
## 41 41 744211 147327 14.9180200 11.926080
## 66 66 879581 146058 115.2039000 3.876797
## 57 57 699306 122180 24.3485700 2.956879
Use R to draw a scatter plot of Profit vs. MTenure.
library(car)
##
## Attaching package: 'car'
## The following object is masked from 'package:psych':
##
## logit
scatterplot(stores.df$MTenure,stores.df$Profit,main = "Scatterplot of Profit Vs MTenure",xlab = "MTenure",ylab = "Profit",lwd = 2,smoother = FALSE)
lw1 <- loess(Profit~MTenure,data = stores.df)
j <- order(stores.df$MTenure)
lines(stores.df$MTenure[j],lw1$fitted[j],col="red",lwd = 2,lty="dashed")
##TASK 4h - Scatter Plots (contd.) Use R to draw a scatter plot of Profit vs. CTenure.
library(car)
scatterplot(stores.df$CTenure,stores.df$Profit,main = "Scatterplot of Profit Vs CTenure",xlab = "CTenure",ylab = "Profit",lwd = 2,smoother = FALSE)
lw1 <- loess(Profit~CTenure,data = stores.df)
j <- order(stores.df$CTenure)
lines(stores.df$CTenure[j],lw1$fitted[j],col="red",lwd = 2,lty="dashed")
##Task 4i- Use R to construct a Correlation Matrix for all the variables in the dataset. (Display the numbers up to 2 Decimal places)
cor <- cor(stores.df)
round(cor,2)
## store Sales Profit MTenure CTenure Pop Comp Visibility
## store 1.00 -0.23 -0.20 -0.06 0.02 -0.29 0.03 -0.03
## Sales -0.23 1.00 0.92 0.45 0.25 0.40 -0.24 0.13
## Profit -0.20 0.92 1.00 0.44 0.26 0.43 -0.33 0.14
## MTenure -0.06 0.45 0.44 1.00 0.24 -0.06 0.18 0.16
## CTenure 0.02 0.25 0.26 0.24 1.00 0.00 -0.07 0.07
## Pop -0.29 0.40 0.43 -0.06 0.00 1.00 -0.27 -0.05
## Comp 0.03 -0.24 -0.33 0.18 -0.07 -0.27 1.00 0.03
## Visibility -0.03 0.13 0.14 0.16 0.07 -0.05 0.03 1.00
## PedCount -0.22 0.42 0.45 0.06 -0.08 0.61 -0.15 -0.14
## Res -0.03 -0.17 -0.16 -0.06 -0.34 -0.24 0.22 0.02
## Hours24 0.03 0.06 -0.03 -0.17 0.07 -0.22 0.13 0.05
## CrewSkill 0.05 0.16 0.16 0.10 0.26 0.28 -0.04 -0.20
## MgrSkill -0.07 0.31 0.32 0.23 0.12 0.08 0.22 0.07
## ServQual -0.32 0.39 0.36 0.18 0.08 0.12 0.02 0.21
## PedCount Res Hours24 CrewSkill MgrSkill ServQual
## store -0.22 -0.03 0.03 0.05 -0.07 -0.32
## Sales 0.42 -0.17 0.06 0.16 0.31 0.39
## Profit 0.45 -0.16 -0.03 0.16 0.32 0.36
## MTenure 0.06 -0.06 -0.17 0.10 0.23 0.18
## CTenure -0.08 -0.34 0.07 0.26 0.12 0.08
## Pop 0.61 -0.24 -0.22 0.28 0.08 0.12
## Comp -0.15 0.22 0.13 -0.04 0.22 0.02
## Visibility -0.14 0.02 0.05 -0.20 0.07 0.21
## PedCount 1.00 -0.28 -0.28 0.21 0.09 -0.01
## Res -0.28 1.00 -0.09 -0.15 -0.03 0.09
## Hours24 -0.28 -0.09 1.00 0.11 -0.04 0.06
## CrewSkill 0.21 -0.15 0.11 1.00 -0.02 -0.03
## MgrSkill 0.09 -0.03 -0.04 -0.02 1.00 0.36
## ServQual -0.01 0.09 0.06 -0.03 0.36 1.00
Use R to measure the correlation between Profit and MTenure. (Display the numbers up to 2 Decimal places)
round(cor(Profit,MTenure),2)
## [1] 0.44
Use R to measure the correlation between Profit and CTenure. (Display the numbers up to 2 Decimal places)
round(cor(Profit,CTenure),2)
## [1] 0.26
Use R to construct the following Corrgram based on all variables in the dataset.
library(corrgram)
corrgram(stores.df,lower.panel = panel.shade,upper.panel=panel.pie,text.panel = panel.txt,main="Corrgram of Store Variables")
##Task 4l 4 L1- Run a Pearson’s Correlation test on the correlation between Profit and MTenure. What is the p-value?
cor.test(Profit,MTenure)
##
## Pearson's product-moment correlation
##
## data: Profit and MTenure
## t = 4.1731, df = 73, p-value = 8.193e-05
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
## 0.2353497 0.6055175
## sample estimates:
## cor
## 0.4388692
4 L2-Run a Pearson’s Correlation test on the correlation between Profit and CTenure. What is the p-value?
cor.test(Profit,CTenure)
##
## Pearson's product-moment correlation
##
## data: Profit and CTenure
## t = 2.2786, df = 73, p-value = 0.02562
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
## 0.03262507 0.45786339
## sample estimates:
## cor
## 0.2576789
4 M1Run a regression of Profit on {MTenure, CTenure Comp, Pop, PedCount, Res,Hours24, Visibility}.
model <- lm(Profit~MTenure+CTenure+Comp+Pop+PedCount+Res+Hours24+Visibility)
model
##
## Call:
## lm(formula = Profit ~ MTenure + CTenure + Comp + Pop + PedCount +
## Res + Hours24 + Visibility)
##
## Coefficients:
## (Intercept) MTenure CTenure Comp Pop
## 7610.041 760.993 944.978 -25286.887 3.667
## PedCount Res Hours24 Visibility
## 34087.359 91584.675 63233.307 12625.447
summary(model)
##
## Call:
## lm(formula = Profit ~ MTenure + CTenure + Comp + Pop + PedCount +
## Res + Hours24 + Visibility)
##
## Residuals:
## Min 1Q Median 3Q Max
## -105789 -35946 -7069 33780 112390
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 7610.041 66821.994 0.114 0.909674
## MTenure 760.993 127.086 5.988 9.72e-08 ***
## CTenure 944.978 421.687 2.241 0.028400 *
## Comp -25286.887 5491.937 -4.604 1.94e-05 ***
## Pop 3.667 1.466 2.501 0.014890 *
## PedCount 34087.359 9073.196 3.757 0.000366 ***
## Res 91584.675 39231.283 2.334 0.022623 *
## Hours24 63233.307 19641.114 3.219 0.001994 **
## Visibility 12625.447 9087.620 1.389 0.169411
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 56970 on 66 degrees of freedom
## Multiple R-squared: 0.6379, Adjusted R-squared: 0.594
## F-statistic: 14.53 on 8 and 66 DF, p-value: 5.382e-12
List the explanatory variable(s) whose beta-coefficients are statistically significant(p < 0.05). 1. MTenure: Average manager tenure during FY-2000 where tenure is defined as the number of months of experience with Store24 2. CTenure: Average crew tenure during FY-2000 where tenure is defined as the number of months of experience with Store24 4. PedCount: 5-point rating on pedestrian foot traffic volume with 5 being the highest 5. CrewSkill: Skill of Crew in the store (rating out of 5) 6. MgrSkill: Skill of Manager in the store (rating out of 5) 7. ServQual: Service Quality
List the explanatory variable(s) whose beta-coefficients are not statistically significant(p > 0.05). 1. Visibility: 5-point rating on visibility of store front with 5 being the highest 2. Pop: Population within a ½ mile radius
4 O1-What is expected change in the Profit at a store, if the Manager’s tenure i.e. number of months of experience with Store24, increases by one month?
model$coefficients[2]
## MTenure
## 760.9927
4 O2-What is expected change in the Profit at a store, if the Crew’s tenure i.e. number of months of experience with Store24, increases by one month?
model$coefficients[3]
## CTenure
## 944.978
From the above corrgram we obtained that Profit is correlated to MTenure, CTenure, Pop, CrewSkill, MgrSkill and ServQual. from the regression analysis that the an increase in Manager’s experience with Store24 can increase the store’s profit by 760.993. from the regression analysis that the an increase in Crew’s experience with Store24 can increase the store’s profit by 944.978.