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airline <- read.csv(paste("SixAirlinesData.csv", sep=""))

Summary of the data

summary(airline)
##       Airline      Aircraft   FlightDuration   TravelMonth
##  AirFrance: 74   AirBus:151   Min.   : 1.250   Aug:127    
##  British  :175   Boeing:307   1st Qu.: 4.260   Jul: 75    
##  Delta    : 46                Median : 7.790   Oct:127    
##  Jet      : 61                Mean   : 7.578   Sep:129    
##  Singapore: 40                3rd Qu.:10.620              
##  Virgin   : 62                Max.   :14.660              
##       IsInternational  SeatsEconomy    SeatsPremium    PitchEconomy  
##  Domestic     : 40    Min.   : 78.0   Min.   : 8.00   Min.   :30.00  
##  International:418    1st Qu.:133.0   1st Qu.:21.00   1st Qu.:31.00  
##                       Median :185.0   Median :36.00   Median :31.00  
##                       Mean   :202.3   Mean   :33.65   Mean   :31.22  
##                       3rd Qu.:243.0   3rd Qu.:40.00   3rd Qu.:32.00  
##                       Max.   :389.0   Max.   :66.00   Max.   :33.00  
##   PitchPremium    WidthEconomy    WidthPremium    PriceEconomy 
##  Min.   :34.00   Min.   :17.00   Min.   :17.00   Min.   :  65  
##  1st Qu.:38.00   1st Qu.:18.00   1st Qu.:19.00   1st Qu.: 413  
##  Median :38.00   Median :18.00   Median :19.00   Median :1242  
##  Mean   :37.91   Mean   :17.84   Mean   :19.47   Mean   :1327  
##  3rd Qu.:38.00   3rd Qu.:18.00   3rd Qu.:21.00   3rd Qu.:1909  
##  Max.   :40.00   Max.   :19.00   Max.   :21.00   Max.   :3593  
##   PricePremium    PriceRelative      SeatsTotal  PitchDifference 
##  Min.   :  86.0   Min.   :0.0200   Min.   : 98   Min.   : 2.000  
##  1st Qu.: 528.8   1st Qu.:0.1000   1st Qu.:166   1st Qu.: 6.000  
##  Median :1737.0   Median :0.3650   Median :227   Median : 7.000  
##  Mean   :1845.3   Mean   :0.4872   Mean   :236   Mean   : 6.688  
##  3rd Qu.:2989.0   3rd Qu.:0.7400   3rd Qu.:279   3rd Qu.: 7.000  
##  Max.   :7414.0   Max.   :1.8900   Max.   :441   Max.   :10.000  
##  WidthDifference PercentPremiumSeats
##  Min.   :0.000   Min.   : 4.71      
##  1st Qu.:1.000   1st Qu.:12.28      
##  Median :1.000   Median :13.21      
##  Mean   :1.633   Mean   :14.65      
##  3rd Qu.:3.000   3rd Qu.:15.36      
##  Max.   :4.000   Max.   :24.69
library(psych)
describe(airline)
##                     vars   n    mean      sd  median trimmed     mad   min
## Airline*               1 458    3.01    1.65    2.00    2.89    1.48  1.00
## Aircraft*              2 458    1.67    0.47    2.00    1.71    0.00  1.00
## FlightDuration         3 458    7.58    3.54    7.79    7.57    4.81  1.25
## TravelMonth*           4 458    2.56    1.17    3.00    2.58    1.48  1.00
## IsInternational*       5 458    1.91    0.28    2.00    2.00    0.00  1.00
## SeatsEconomy           6 458  202.31   76.37  185.00  194.64   85.99 78.00
## SeatsPremium           7 458   33.65   13.26   36.00   33.35   11.86  8.00
## PitchEconomy           8 458   31.22    0.66   31.00   31.26    0.00 30.00
## PitchPremium           9 458   37.91    1.31   38.00   38.05    0.00 34.00
## WidthEconomy          10 458   17.84    0.56   18.00   17.81    0.00 17.00
## WidthPremium          11 458   19.47    1.10   19.00   19.53    0.00 17.00
## PriceEconomy          12 458 1327.08  988.27 1242.00 1244.40 1159.39 65.00
## PricePremium          13 458 1845.26 1288.14 1737.00 1799.05 1845.84 86.00
## PriceRelative         14 458    0.49    0.45    0.36    0.42    0.41  0.02
## SeatsTotal            15 458  235.96   85.29  227.00  228.73   90.44 98.00
## PitchDifference       16 458    6.69    1.76    7.00    6.76    0.00  2.00
## WidthDifference       17 458    1.63    1.19    1.00    1.53    0.00  0.00
## PercentPremiumSeats   18 458   14.65    4.84   13.21   14.31    2.68  4.71
##                         max   range  skew kurtosis    se
## Airline*               6.00    5.00  0.61    -0.95  0.08
## Aircraft*              2.00    1.00 -0.72    -1.48  0.02
## FlightDuration        14.66   13.41 -0.07    -1.12  0.17
## TravelMonth*           4.00    3.00 -0.14    -1.46  0.05
## IsInternational*       2.00    1.00 -2.91     6.50  0.01
## SeatsEconomy         389.00  311.00  0.72    -0.36  3.57
## SeatsPremium          66.00   58.00  0.23    -0.46  0.62
## PitchEconomy          33.00    3.00 -0.03    -0.35  0.03
## PitchPremium          40.00    6.00 -1.51     3.52  0.06
## WidthEconomy          19.00    2.00 -0.04    -0.08  0.03
## WidthPremium          21.00    4.00 -0.08    -0.31  0.05
## PriceEconomy        3593.00 3528.00  0.51    -0.88 46.18
## PricePremium        7414.00 7328.00  0.50     0.43 60.19
## PriceRelative          1.89    1.87  1.17     0.72  0.02
## SeatsTotal           441.00  343.00  0.70    -0.53  3.99
## PitchDifference       10.00    8.00 -0.54     1.78  0.08
## WidthDifference        4.00    4.00  0.84    -0.53  0.06
## PercentPremiumSeats   24.69   19.98  0.71     0.28  0.23

Histograms

hist(airline$FlightDuration, breaks = 5,col="Green Yellow",main="Histogram of flight duration")

hist(airline$SeatsEconomy, breaks = 5,col="Green Yellow",main="Histogram of seats in economy")

hist(airline$SeatsPremium, breaks = 5,col="Green Yellow",main="Histogram of seats in premium")

hist(airline$WidthEconomy, breaks = 5,col="Green Yellow",main="Histogram of width in economy")

hist(airline$WidthPremium, breaks = 5,col="Green Yellow",main="Histogram of width in premium")

Boxplots

boxplot(airline$FlightDuration  , horizontal =FALSE, main="Boxplot of Flight Duration" ,col="darkolivegreen1")

boxplot(airline$PriceEconomy  , horizontal =FALSE, main="Boxplot of Price of Economy class" ,col="darkolivegreen1")

boxplot(airline$PricePremium  , horizontal =FALSE, main="Boxplot of Price of Premium class",col="darkolivegreen1" )

boxplot(airline$WidthEconomy  , horizontal =FALSE, main="Boxplot of WidthEconomy",col="darkolivegreen1" )

boxplot(airline$WidthPremium  , horizontal =FALSE, main="Boxplot of WidthPremium",col="darkolivegreen1" )

plot(airline$Airline, airline$SeatsEconomy, main="Airline vs No. of seats in Economy Class",col="darkolivegreen1")

plot(airline$Airline, airline$SeatsPremium, main="Airline vs No. of seats in Premium Class",col="darkolivegreen1")

ScatterPlots

library(car)
## 
## Attaching package: 'car'
## The following object is masked from 'package:psych':
## 
##     logit
scatterplot(x = airline$PriceRelative , y = airline$WidthDifference, main="Comparison of width", xlab="Relative prices", ylab="Width difference")

scatterplot(x = airline$PriceRelative , y = airline$PitchDifference, main="Comparison of pitch" , xlab="Relative prices", ylab="Pitch difference")

Correlation matrix

round(cor(airline[,6:18]),2)
##                     SeatsEconomy SeatsPremium PitchEconomy PitchPremium
## SeatsEconomy                1.00         0.63         0.14         0.12
## SeatsPremium                0.63         1.00        -0.03         0.00
## PitchEconomy                0.14        -0.03         1.00        -0.55
## PitchPremium                0.12         0.00        -0.55         1.00
## WidthEconomy                0.37         0.46         0.29        -0.02
## WidthPremium                0.10         0.00        -0.54         0.75
## PriceEconomy                0.13         0.11         0.37         0.05
## PricePremium                0.18         0.22         0.23         0.09
## PriceRelative               0.00        -0.10        -0.42         0.42
## SeatsTotal                  0.99         0.72         0.12         0.11
## PitchDifference             0.04         0.02        -0.78         0.95
## WidthDifference            -0.08        -0.22        -0.64         0.70
## PercentPremiumSeats        -0.33         0.49        -0.10        -0.18
##                     WidthEconomy WidthPremium PriceEconomy PricePremium
## SeatsEconomy                0.37         0.10         0.13         0.18
## SeatsPremium                0.46         0.00         0.11         0.22
## PitchEconomy                0.29        -0.54         0.37         0.23
## PitchPremium               -0.02         0.75         0.05         0.09
## WidthEconomy                1.00         0.08         0.07         0.15
## WidthPremium                0.08         1.00        -0.06         0.06
## PriceEconomy                0.07        -0.06         1.00         0.90
## PricePremium                0.15         0.06         0.90         1.00
## PriceRelative              -0.04         0.50        -0.29         0.03
## SeatsTotal                  0.41         0.09         0.13         0.19
## PitchDifference            -0.13         0.76        -0.10        -0.02
## WidthDifference            -0.39         0.88        -0.08        -0.01
## PercentPremiumSeats         0.23        -0.18         0.07         0.12
##                     PriceRelative SeatsTotal PitchDifference
## SeatsEconomy                 0.00       0.99            0.04
## SeatsPremium                -0.10       0.72            0.02
## PitchEconomy                -0.42       0.12           -0.78
## PitchPremium                 0.42       0.11            0.95
## WidthEconomy                -0.04       0.41           -0.13
## WidthPremium                 0.50       0.09            0.76
## PriceEconomy                -0.29       0.13           -0.10
## PricePremium                 0.03       0.19           -0.02
## PriceRelative                1.00      -0.01            0.47
## SeatsTotal                  -0.01       1.00            0.03
## PitchDifference              0.47       0.03            1.00
## WidthDifference              0.49      -0.11            0.76
## PercentPremiumSeats         -0.16      -0.22           -0.09
##                     WidthDifference PercentPremiumSeats
## SeatsEconomy                  -0.08               -0.33
## SeatsPremium                  -0.22                0.49
## PitchEconomy                  -0.64               -0.10
## PitchPremium                   0.70               -0.18
## WidthEconomy                  -0.39                0.23
## WidthPremium                   0.88               -0.18
## PriceEconomy                  -0.08                0.07
## PricePremium                  -0.01                0.12
## PriceRelative                  0.49               -0.16
## SeatsTotal                    -0.11               -0.22
## PitchDifference                0.76               -0.09
## WidthDifference                1.00               -0.28
## PercentPremiumSeats           -0.28                1.00

Corrgram

library(corrgram)
corrgram(airline, order=FALSE, lower.panel=panel.shade,
         upper.panel=panel.pie, text.panel=panel.txt,
         main="Corrgram of Airline variables ")

attach(airline)
t.test(PriceRelative,FlightDuration)
## 
##  Welch Two Sample t-test
## 
## data:  PriceRelative and FlightDuration
## t = -42.499, df = 471.79, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -7.418482 -6.762785
## sample estimates:
## mean of x mean of y 
## 0.4872052 7.5778384

Here our null hypothesis is:There is no significant impact of duration of journey on price.Result:Null hypothesis is rejected.

t.test(PriceRelative,WidthDifference)
## 
##  Welch Two Sample t-test
## 
## data:  PriceRelative and WidthDifference
## t = -19.284, df = 585.55, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -1.262697 -1.029268
## sample estimates:
## mean of x mean of y 
## 0.4872052 1.6331878

Here our null hypothesis is:There is no significant impact of width difference on price.Result:Null hypothesis is rejected.

t.test(PriceRelative,PitchDifference)
## 
##  Welch Two Sample t-test
## 
## data:  PriceRelative and PitchDifference
## t = -72.974, df = 516.54, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
##  -6.367495 -6.033640
## sample estimates:
## mean of x mean of y 
## 0.4872052 6.6877729

Here our null hypothesis is:There is no significant impact of pitch difference on price.Result:Null hypothesis is rejected.

fit <- lm(PriceRelative ~ WidthDifference + PitchDifference + FlightDuration, data=airline)
summary(fit)
## 
## Call:
## lm(formula = PriceRelative ~ WidthDifference + PitchDifference + 
##     FlightDuration, data = airline)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -0.74824 -0.28372 -0.06032  0.16447  1.15720 
## 
## Coefficients:
##                  Estimate Std. Error t value Pr(>|t|)    
## (Intercept)     -0.254902   0.088846  -2.869 0.004309 ** 
## WidthDifference  0.129969   0.023356   5.565  4.5e-08 ***
## PitchDifference  0.054755   0.015667   3.495 0.000521 ***
## FlightDuration   0.021597   0.005092   4.241  2.7e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 0.3816 on 454 degrees of freedom
## Multiple R-squared:  0.2876, Adjusted R-squared:  0.2828 
## F-statistic: 61.08 on 3 and 454 DF,  p-value: < 2.2e-16

From the regression model,we can conclude that: 1.There is a significant relation between price of tickets and width difference,pitch difference and flight duration.

2.The model is a good fit model as p value is very less than 0.05.

3.Parameters Width difference,pitch difference and flight duration are statistically significant as their p-values <0.05.These variables explain the difference between price of economy class and price of premium class.

4.Mathematical equation:y(relative price)=-0.25+(0.12WidthDifference)+(0.054PitchDifference)+0.021*FlightDuration