An online bidding is an auction which is held over the internet.Online biddings come in various formats,but most popular of them are the Ascending English auctions,Descending Dutch auctions,First-price Sealed-bid,Vickrey auctions,or sometimes even a combination of multiple auctions,taking elements of one and fusing them with those of another.The scope and reach of these auctions have been propelled by the Internet to a level beyond what the initial purveyors had anticipated.This is mainly because online auctions break down and eliminate all the physical limitations of traditional auctions such as geography,presence,time,space,and a small target audience.This influx in reachability has also made it easier to commit unlawful actions within an auction.In 2002,online auctions were reported to account for 30% of all online e-commerce transactions due to the rapid expansion and the popularity of various forms of electronic commerce.
The analysis mainly focusses on the study of online bidding which takes place on eBay.eBay is a publicly visible market which has attracted a lot of attention from economists,who have been using it to analyze various aspects of buying and selling behavior,auction formats,etc. and comparing them with previous theoretical and empirical findings.Computer Information Systems Researchers have also shown a lot of interest in eBay.Michael Goul,Chairman of the Computer Information Systems Department of the W.P.Carey School of Business at Arizona State University,has published an academic case study based on eBay’s big data management and use in which he discusses how eBay is a data-driven company that processes 50 petabytes of data per day.eBay uses a system that allows different departments in the company to check out data from their data-mart into sandboxes for analysis.According to Goul,eBay has already experienced a huge business success through its data analytics stream.eBay employs 5,000 data analysts to enable data-driven decision making.
Hypothesis : During any online auction,the Final Selling Price of the Product is always greater than the Proxy Bid
For this study,I had collected the data from http://www.modelingonlineauctions.com/datasets. What is the ‘Winner’s Curse’?The Winner’s Curse is a tendency in an auction for the winning bid to exceed the intrinsic value of the item purchased.Because of incomplete information,emotions or any other number of factors regarding the item being auctioned,bidders can have a difficult time in determining the item’s intrinsic value.As a result,the largest over-estimation of an item’s value ends up winning the auction.
In order to test the above Hypothesis,we can propose the following model : price=k0+k1(bid)+k2(openbid)+k3(bidderrate)
Let’s start analyzing the given dataset to get the insights.
setwd("C:/Users/rishu/Downloads")
bid.df <- read.csv(paste("CartierForWinnersCurse.csv", sep="new"))
View(bid.df)
library(psych)
attach(bid.df)
describe(bid.df)
## vars n mean sd median trimmed
## auctionid 1 1348 1.644515e+09 3597127.86 1.644198e+09 1.644464e+09
## bid 2 1348 5.985700e+02 659.81 3.530000e+02 4.822600e+02
## bidtime 3 1348 4.010000e+00 2.50 4.170000e+00 4.090000e+00
## bidder* 4 1348 2.576500e+02 148.11 2.675000e+02 2.584400e+02
## bidderrate 5 1348 3.386000e+01 87.51 6.000000e+00 1.550000e+01
## openbid 6 1348 1.486800e+02 373.16 5.000000e+00 7.391000e+01
## price 7 1348 9.613100e+02 812.41 6.232600e+02 8.400900e+02
## mad min max range skew kurtosis
## auctionid 4642816.76 1638843936.00 1650986455 12142519.00 0.18 -1.12
## bid 375.10 1.00 5400 5399.00 2.32 8.69
## bidtime 3.82 0.01 7 6.99 -0.14 -1.57
## bidder* 190.51 1.00 509 508.00 -0.07 -1.22
## bidderrate 8.90 -4.00 1303 1307.00 7.59 82.65
## openbid 7.40 0.01 5000 4999.99 7.56 85.25
## price 545.98 103.50 5400 5296.50 1.53 3.01
## se
## auctionid 97974.02
## bid 17.97
## bidtime 0.07
## bidder* 4.03
## bidderrate 2.38
## openbid 10.16
## price 22.13
summary(bid.df)
## auctionid bid bidtime
## Min. :1.639e+09 Min. : 1.0 Min. :0.007535
## 1st Qu.:1.642e+09 1st Qu.: 151.7 1st Qu.:1.505715
## Median :1.644e+09 Median : 353.0 Median :4.170885
## Mean :1.645e+09 Mean : 598.6 Mean :4.005524
## 3rd Qu.:1.648e+09 3rd Qu.: 821.5 3rd Qu.:6.725284
## Max. :1.651e+09 Max. :5400.0 Max. :6.999965
##
## bidder bidderrate openbid price
## lass1004 : 22 Min. : -4.00 Min. : 0.01 Min. : 103.5
## pascal1666 : 19 1st Qu.: 1.00 1st Qu.: 1.00 1st Qu.: 355.0
## freembd : 17 Median : 6.00 Median : 5.00 Median : 623.3
## happyrova : 17 Mean : 33.86 Mean : 148.68 Mean : 961.3
## restdynamics: 17 3rd Qu.: 31.00 3rd Qu.: 155.00 3rd Qu.:1525.0
## adammurry : 16 Max. :1303.00 Max. :5000.00 Max. :5400.0
## (Other) :1240
describe(auctionid) ## Unique Identifier of an Auction
## vars n mean sd median trimmed mad min
## X1 1 1348 1644515087 3597128 1644197869 1644463742 4642817 1638843936
## max range skew kurtosis se
## X1 1650986455 12142519 0.18 -1.12 97974.02
describe(bid) ## The Proxy Bid placed by a Bidder
## vars n mean sd median trimmed mad min max range skew
## X1 1 1348 598.57 659.81 353 482.26 375.1 1 5400 5399 2.32
## kurtosis se
## X1 8.69 17.97
describe(bidtime) ## The Time from the start of the auction when the bid was placed
## vars n mean sd median trimmed mad min max range skew kurtosis
## X1 1 1348 4.01 2.5 4.17 4.09 3.82 0.01 7 6.99 -0.14 -1.57
## se
## X1 0.07
describe(bidderrate) ## eBay Feedback Rating of the Bidder
## vars n mean sd median trimmed mad min max range skew kurtosis
## X1 1 1348 33.86 87.51 6 15.5 8.9 -4 1303 1307 7.59 82.65
## se
## X1 2.38
describe(openbid) ## The Opening Bid set by the Seller
## vars n mean sd median trimmed mad min max range skew
## X1 1 1348 148.68 373.16 5 73.91 7.4 0.01 5000 4999.99 7.56
## kurtosis se
## X1 85.25 10.16
describe(price) ## The Closing Price that the item was sold for(highest bid+an increment)
## vars n mean sd median trimmed mad min max range skew
## X1 1 1348 961.31 812.41 623.26 840.09 545.98 103.5 5400 5296.5 1.53
## kurtosis se
## X1 3.01 22.13
library(lattice)
histogram(~price, data = bid.df,main = "Distribution of Price Difference", xlab="Difference in Price",col='green' )
library(car)
##
## Attaching package: 'car'
## The following object is masked from 'package:psych':
##
## logit
library(psych)
scatterplot(price ~ openbid ,data=bid.df, main="ScatterPlot of Price versus OpenBid ")
scatterplot(bid ~ openbid ,data=bid.df, main="ScatterPlot of ProxyBid versus OpenBid ")
scatterplotMatrix(~openbid+price+bid+bidderrate+bidtime, data=bid.df,main="Interdependence Variations among Various Fields")
library(Hmisc)
## Loading required package: survival
## Loading required package: Formula
## Loading required package: ggplot2
##
## Attaching package: 'ggplot2'
## The following objects are masked from 'package:psych':
##
## %+%, alpha
##
## Attaching package: 'Hmisc'
## The following object is masked from 'package:psych':
##
## describe
## The following objects are masked from 'package:base':
##
## format.pval, units
colbid <- c("price","openbid","bid","bidderrate")
corMatrix <- rcorr(as.matrix(bid.df[,colbid]))
corMatrix
## price openbid bid bidderrate
## price 1.00 0.42 0.82 -0.07
## openbid 0.42 1.00 0.56 0.02
## bid 0.82 0.56 1.00 -0.04
## bidderrate -0.07 0.02 -0.04 1.00
##
## n= 1348
##
##
## P
## price openbid bid bidderrate
## price 0.0000 0.0000 0.0087
## openbid 0.0000 0.0000 0.4164
## bid 0.0000 0.0000 0.1759
## bidderrate 0.0087 0.4164 0.1759
library(corrgram)
corrgram(bid.df[,colbid],order=TRUE,main="Difference in Biddings",lower.panel=panel.pts,upper.panel=panel.pie,diag.panel=panel.minmax, text.panel=panel.txt)
t.test(price, bid)
##
## Welch Two Sample t-test
##
## data: price and bid
## t = 12.725, df = 2585.3, p-value < 2.2e-16
## alternative hypothesis: true difference in means is not equal to 0
## 95 percent confidence interval:
## 306.8423 418.6353
## sample estimates:
## mean of x mean of y
## 961.3078 598.5690
The sole purpose of this project was to analyze the Winners curse Effect among the bidders.So from the above analysis of the given dataset,we can deduce that the Final Selling Price of the Product is always greater than the Proxy Bid.
About the Winner’s Curse Effect -> https://www.investopedia.com/terms/w/winnerscurse.asp Details about eBay -> https://en.wikipedia.org/wiki/EBay Source of the Dataset -> http://www.modelingonlineauctions.com/datasets