Watching Competitors
2026-02-10
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# Competitive Intelligence: Spirit Airlines Financial Dossier (R)
# install required packages
# bring packages into the workspace
library(RCurl) # functions for gathering data from the web
library(XML) # XML and HTML parsing
library(quantmod) # use for gathering and charting economic data## Loading required package: xts## Loading required package: zoo##
## Attaching package: 'zoo'## The following objects are masked from 'package:base':
##
## as.Date, as.Date.numeric## Loading required package: TTR## Registered S3 method overwritten by 'quantmod':
## method from
## as.zoo.data.frame zoo# online documentation for quantmod at <http://www.quantmod.com/>
library(Quandl) # extensive financial data online
# online documentation for Quandl at <http://www.quandl.com/>
library(lubridate) # date functions##
## Attaching package: 'lubridate'## The following objects are masked from 'package:base':
##
## date, intersect, setdiff, unionlibrary(zoo) # utilities for working with time series
library(xts) # utilities for working with time series
library(ggplot2) # data visualization
# ----------------------------------
# Text data acquisition and storage
# ----------------------------------
# similar procedures may be used for all acquired data
# for the Spirit Airlines competitive intelligence study
# use distinct file names to identify the data sources
# ---------------------------------------------------------------
# Yahoo! Finance for Spirit Airlines (NASDAQ stock symbol: TSLA)
# ---------------------------------------------------------------
# stock symbols for companies can be obtained from Yahoo! Finance
# <http://finance.yahoo.com/lookup>
# get Spirit Airlines stock price data
getSymbols("TSLA", return.class = "xts", src = "yahoo")## [1] "TSLA"print(str(TSLA)) # show the structure of this xtx time series object## An xts object on 2010-06-29 / 2026-02-09 containing:
## Data: double [3928, 6]
## Columns: TSLA.Open, TSLA.High, TSLA.Low, TSLA.Close, TSLA.Volume ... with 1 more column
## Index: Date [3928] (TZ: "UTC")
## xts Attributes:
## $ src : chr "yahoo"
## $ updated: POSIXct[1:1], format: "2026-02-10 02:30:55"
## NULL# plot the series stock price
chartSeries(TSLA,theme="white")
# examine the structure of the R data object
print(str(TSLA))## An xts object on 2010-06-29 / 2026-02-09 containing:
## Data: double [3928, 6]
## Columns: TSLA.Open, TSLA.High, TSLA.Low, TSLA.Close, TSLA.Volume ... with 1 more column
## Index: Date [3928] (TZ: "UTC")
## xts Attributes:
## $ src : chr "yahoo"
## $ updated: POSIXct[1:1], format: "2026-02-10 02:30:55"
## NULLprint(TSLA)## TSLA.Open TSLA.High TSLA.Low TSLA.Close TSLA.Volume
## 2010-06-29 1.266667 1.666667 1.169333 1.592667 281494500
## 2010-06-30 1.719333 2.028000 1.553333 1.588667 257806500
## 2010-07-01 1.666667 1.728000 1.351333 1.464000 123282000
## 2010-07-02 1.533333 1.540000 1.247333 1.280000 77097000
## 2010-07-06 1.333333 1.333333 1.055333 1.074000 103003500
## 2010-07-07 1.093333 1.108667 0.998667 1.053333 103825500
## 2010-07-08 1.076000 1.168000 1.038000 1.164000 115671000
## 2010-07-09 1.172000 1.193333 1.103333 1.160000 60759000
## 2010-07-12 1.196667 1.204667 1.133333 1.136667 33037500
## 2010-07-13 1.159333 1.242667 1.126667 1.209333 40201500
## ...
## 2026-01-27 437.410004 437.519989 430.690002 430.899994 37733100
## 2026-01-28 431.910004 438.260010 430.100006 431.459991 54857400
## 2026-01-29 437.799988 440.230011 414.619995 416.559998 81686100
## 2026-01-30 425.350006 439.880005 422.700012 430.410004 82626100
## 2026-02-02 421.290009 427.149994 414.500000 421.809998 58739500
## 2026-02-03 424.269989 428.559998 413.690002 421.959991 56886500
## 2026-02-04 420.459991 423.899994 399.179993 406.010010 74606900
## 2026-02-05 397.019989 402.100006 387.529999 397.209991 72819800
## 2026-02-06 400.869995 414.549988 397.750000 411.109985 62677100
## 2026-02-09 409.910004 421.250000 407.290009 417.320007 54351900
## TSLA.Adjusted
## 2010-06-29 1.592667
## 2010-06-30 1.588667
## 2010-07-01 1.464000
## 2010-07-02 1.280000
## 2010-07-06 1.074000
## 2010-07-07 1.053333
## 2010-07-08 1.164000
## 2010-07-09 1.160000
## 2010-07-12 1.136667
## 2010-07-13 1.209333
## ...
## 2026-01-27 430.899994
## 2026-01-28 431.459991
## 2026-01-29 416.559998
## 2026-01-30 430.410004
## 2026-02-02 421.809998
## 2026-02-03 421.959991
## 2026-02-04 406.010010
## 2026-02-05 397.209991
## 2026-02-06 411.109985
## 2026-02-09 417.320007# convert character string row names to decimal date for the year
Year <- decimal_date(ymd(row.names(as.data.frame(TSLA))))
# Obtain the closing price of Spirit Airlines stock
Price <- as.numeric(TSLA$TSLA.Close)
# create data frame for Spirit Airlines Year and Price for future plots
SPIRIT_data_frame <- data.frame(Year, Price)
# similar procedures may be used for all airline competitors
# ---------------------------------------------------------------
# Google! Finance for Spirit Airlines (NASDAQ stock symbol: TSLA)
# (basically the same data as from Yahoo! Finance)
# ---------------------------------------------------------------
# get Spirit Airlines stock price data
getSymbols("TSLA", return.class = "xts", src = "yahoo")## [1] "TSLA"print(str(TSLA)) # show the structure of this xtx time series object## An xts object on 2010-06-29 / 2026-02-09 containing:
## Data: double [3928, 6]
## Columns: TSLA.Open, TSLA.High, TSLA.Low, TSLA.Close, TSLA.Volume ... with 1 more column
## Index: Date [3928] (TZ: "UTC")
## xts Attributes:
## $ src : chr "yahoo"
## $ updated: POSIXct[1:1], format: "2026-02-10 02:30:55"
## NULL# plot the series stock price
chartSeries(TSLA,theme="white")
# examine the structure of the R data object
print(str(TSLA))## An xts object on 2010-06-29 / 2026-02-09 containing:
## Data: double [3928, 6]
## Columns: TSLA.Open, TSLA.High, TSLA.Low, TSLA.Close, TSLA.Volume ... with 1 more column
## Index: Date [3928] (TZ: "UTC")
## xts Attributes:
## $ src : chr "yahoo"
## $ updated: POSIXct[1:1], format: "2026-02-10 02:30:55"
## NULLprint(TSLA)## TSLA.Open TSLA.High TSLA.Low TSLA.Close TSLA.Volume
## 2010-06-29 1.266667 1.666667 1.169333 1.592667 281494500
## 2010-06-30 1.719333 2.028000 1.553333 1.588667 257806500
## 2010-07-01 1.666667 1.728000 1.351333 1.464000 123282000
## 2010-07-02 1.533333 1.540000 1.247333 1.280000 77097000
## 2010-07-06 1.333333 1.333333 1.055333 1.074000 103003500
## 2010-07-07 1.093333 1.108667 0.998667 1.053333 103825500
## 2010-07-08 1.076000 1.168000 1.038000 1.164000 115671000
## 2010-07-09 1.172000 1.193333 1.103333 1.160000 60759000
## 2010-07-12 1.196667 1.204667 1.133333 1.136667 33037500
## 2010-07-13 1.159333 1.242667 1.126667 1.209333 40201500
## ...
## 2026-01-27 437.410004 437.519989 430.690002 430.899994 37733100
## 2026-01-28 431.910004 438.260010 430.100006 431.459991 54857400
## 2026-01-29 437.799988 440.230011 414.619995 416.559998 81686100
## 2026-01-30 425.350006 439.880005 422.700012 430.410004 82626100
## 2026-02-02 421.290009 427.149994 414.500000 421.809998 58739500
## 2026-02-03 424.269989 428.559998 413.690002 421.959991 56886500
## 2026-02-04 420.459991 423.899994 399.179993 406.010010 74606900
## 2026-02-05 397.019989 402.100006 387.529999 397.209991 72819800
## 2026-02-06 400.869995 414.549988 397.750000 411.109985 62677100
## 2026-02-09 409.910004 421.250000 407.290009 417.320007 54351900
## TSLA.Adjusted
## 2010-06-29 1.592667
## 2010-06-30 1.588667
## 2010-07-01 1.464000
## 2010-07-02 1.280000
## 2010-07-06 1.074000
## 2010-07-07 1.053333
## 2010-07-08 1.164000
## 2010-07-09 1.160000
## 2010-07-12 1.136667
## 2010-07-13 1.209333
## ...
## 2026-01-27 430.899994
## 2026-01-28 431.459991
## 2026-01-29 416.559998
## 2026-01-30 430.410004
## 2026-02-02 421.809998
## 2026-02-03 421.959991
## 2026-02-04 406.010010
## 2026-02-05 397.209991
## 2026-02-06 411.109985
## 2026-02-09 417.320007# -----------------------------------------
# ggplot2 time series plotting, closing
# price of Spirit Airlines common stock
# -----------------------------------------
# with a data frame object in hand... we can go on to use ggplot2
# and methods described in Chang (2013) R Graphics Cookbook
# use data frame defined from Yahoo! Finance
# the Spirit Airlines closing price per share SPIRIT_data_frame
# now we use that data structure to prepare a time series plot
# again, let's highlight the Great Recession on our plot for this time series
plotting_object <- ggplot(SPIRIT_data_frame, aes(x = Year, y = Price)) +
geom_line() +
ylab("Stock Price (dollars/share)") +
ggtitle("Spirit Airlines Stock Price")
print(plotting_object) 
# send the plot to an external file (sans title, larger axis labels)
pdf("fig_competitive_intelligence_spirit.pdf", width = 11, height = 8.5)
plotting_object <- ggplot(SPIRIT_data_frame, aes(x = Year, y = Price)) +
geom_line() + ylab("Stock Price (dollars/share)") +
theme(axis.title.y = element_text(size = 20, colour = "black")) +
theme(axis.title.x = element_text(size = 20, colour = "black"))
print(plotting_object)
dev.off()## png
## 2