TURKEY CAR MARKET 2020

1. Introduction

1.1 Turkey Online Car Market 2020

The dataset used in this project belongs to a website in Turkey which makes online buying and selling of cars advertised in 2020. It is called Turkey Car Market 2020 and downloaded from Kaggle. The dataset contains information about features of cars which has been filled by sellers. The missing features of cars in the dataset are written as “Don’t Know”. In order to overcome the rows with missing values, a preprocessing of data is conducted and can be seen in Preprocessing Section for detailed explanations. This section also includes some accuracy checks of the data, and explanations od the variables.

1.2 Objectives

In this project, we will first investigate the data for preprocessing to improve its quality. Then we will perform an exploratory data analysis(EDA) by data manipulation and data visualization steps. The main purpose is to identify which variables affect the price mostly and come up with a conclusion for the relationship between variables. In addition to these, we will study on some models to forecast prices of cars with given features. The processes during the assignment can be listed as below:

  1. Data Preprocessing
  2. Data Manipulation
  3. Data Visualization
  4. Interactive Shiny App
  5. Forecasting

1.3 Used Packages

The packages used during the project can be listed as below:

  1. tidyverse
  2. lubridate
  3. knitr
  4. tinytex
  5. data table
  6. shiny
  7. scales
  8. kableExtra
#Required packages
pti <- c("data.table", "tidyverse", "knitr", "tinytex", "scales", "kableExtra")
pti <- pti[!(pti %in% installed.packages())]
if(length(pti)>0){
    install.packages(pti)
}

library(tidyverse)
library(knitr)
library(tinytex)
library(data.table)
library(scales)
library(kableExtra)

2. Exploratory Data Analysis - EDA

Before making any further analysis, we need to import the data that we pre-processed the data.The pre-processing report file link is given above.

#data uploading
carmarket = readRDS(gzcon(url("https://github.com/pjournal/boun01g-data-mine-r-s/blob/gh-pages/Project/turkey_car_market_EDA?raw=true")))

2.1 Time Series Analyses

In this dataset, there are two variables which are related to time, i.e., Model Year and Advertisement Date. To analyze of the variable relationships, we first present time variables analyses as time series analyses. In the description of the dataset, it is told that this dataset contains the advertisements in 2020 but there are two rows which are from 2019. We will consider that it is not a problem.

carmarket %>%
  group_by(Year) %>%
  summarise(count = n()) %>%
  arrange(Year) %>%
  select(Year, count)%>%
  kable(col.names = c("Advertisement Year", "Count")) %>%
  kable_minimal(full_width = F)
Advertisement Year Count
2019 2
2020 8832

When we look at the bar plot, there are advertisement whose month is changing from march to June and also there are two advertisements from December of 2019. There are more advertisements in April respect to other months. We can look for the daily count of these advertisements.

carmarket %>%
  group_by(Month) %>%
  summarise(count = n()) %>%
  ggplot(., aes(x = as.factor(Month), y = count, fill=count)) +
  geom_col() +
  scale_fill_gradient("count", low="pink2", high="pink4") +
  theme_minimal() +
  theme(legend.position = "none", plot.title = element_text(vjust = 0.5)) +
  labs(title = "Number of Advertisements Over Months",
       subtitle = st,
       x = "Month",
       y = "Number of Advertisement")

carmarket %>%
  group_by(Date) %>%
  summarise(count = n()) %>%
  ggplot(., aes(x = Date, y = count)) +
  geom_line() +
  theme_minimal() +
  labs(title = "Number of Advertisements Over Days",
       subtitle = st,
       x = "Day",
       y = "Number of Advertisement")

There is a big jump in two days of April. So, we can get that with these commands:

carmarket %>%
  group_by(Date) %>%
  summarise(count = n()) %>%
  arrange(desc(count)) %>%
  select(Date, count)%>%
  kable(col.names = c("Date", "Count")) %>%
  kable_styling("striped", full_width = T) %>%
  scroll_box(width = "100%", height = "400px")
Date Count
2020-04-18 3423
2020-04-17 1090
2020-05-12 353
2020-05-27 243
2020-04-22 149
2020-06-13 149
2020-06-12 139
2020-06-09 137
2020-05-01 136
2020-06-11 133
2020-06-16 124
2020-06-14 121
2020-06-15 115
2020-05-17 108
2020-06-08 89
2020-06-03 87
2020-06-02 76
2020-06-10 73
2020-06-01 68
2020-05-29 64
2020-06-05 62
2020-03-25 61
2020-06-06 59
2020-05-20 54
2020-05-28 53
2020-04-08 51
2020-05-30 51
2020-05-21 50
2020-06-07 47
2020-05-16 45
2020-06-04 43
2020-05-18 42
2020-05-13 41
2020-04-09 39
2020-05-09 37
2020-05-14 37
2020-05-06 36
2020-05-15 36
2020-04-02 34
2020-05-08 32
2020-05-11 32
2020-05-05 30
2020-05-22 30
2020-03-27 29
2020-04-01 29
2020-04-07 29
2020-05-19 29
2020-05-31 29
2020-04-30 28
2020-05-02 28
2020-05-03 28
2020-05-07 28
2020-04-29 26
2020-03-24 25
2020-03-26 25
2020-05-24 25
2020-03-19 24
2020-04-23 24
2020-04-13 23
2020-04-16 23
2020-04-20 23
2020-03-20 21
2020-04-10 21
2020-04-21 21
2020-04-24 21
2020-05-10 21
2020-05-23 21
2020-03-21 20
2020-03-22 20
2020-04-03 20
2020-04-27 20
2020-05-04 20
2020-03-28 19
2020-05-25 19
2020-05-26 19
2020-04-19 17
2020-04-28 17
2020-04-06 16
2020-04-15 16
2020-04-25 16
2020-04-11 15
2020-03-23 14
2020-03-29 13
2020-04-04 12
2020-04-05 12
2020-04-26 12
2020-03-30 11
2020-04-14 11
2020-04-12 10
2020-03-31 3
2019-12-23 1
2019-12-24 1

When we search for that increase in 17 - 18.04.2020 dates, there was an information about the sales that march, april and may have most of sales in a year (You can find this information from this link). So, this pick is an expected pick.

We can make a plot of sales respect to Brand.

carmarket  %>%
  group_by(Date, Brand) %>%
  summarise(count = n()) %>%
  ggplot(., aes(x = Date, y = count, color = Brand)) +
  geom_line() +
  theme_minimal() +
  labs(title = "Spread of Advertisement According to Date",
       subtitle = st,
       x = "Date",
       y = "Number of Advertisements",
       color = "Brands")

In the pick period we see that there is a type of brand that is mostly in the advertisement. We can inspect which brand it is. Note that, almost all advertisements accumulate between March and July. For this reason, to provide clear insight, we filter this time interval.

carmarket %>%
  group_by(Date, Brand) %>%
  summarise(count = n()) %>%
  arrange(desc(count)) %>%
  #head(10) %>%
  select(Date, Brand, count)%>%
  kable(col.names = c("Date", "Brand", "Count")) %>%
  kable_styling("striped", full_width = T) %>%
  scroll_box(width = "100%", height = "400px")
Date Brand Count
2020-04-18 Renault 1303
2020-04-18 BMW 241
2020-04-18 Mercedes 201
2020-04-18 Ford 183
2020-04-18 Hyundai 182
2020-04-18 Fiat 180
2020-04-18 Opel 178
2020-04-18 Audi 147
2020-04-18 Peugeot 130
2020-04-17 BMW 125
2020-05-27 Dacia 121
2020-04-17 Mercedes 117
2020-04-17 Audi 101
2020-04-17 Fiat 98
2020-04-17 Opel 93
2020-04-18 Citroen 92
2020-04-18 Skoda 82
2020-04-18 Dacia 81
2020-04-18 Nissan 81
2020-04-17 Ford 78
2020-04-17 Hyundai 76
2020-04-18 Honda 74
2020-04-17 Peugeot 73
2020-05-12 Renault 70
2020-04-18 Kia 65
2020-04-18 Seat 62
2020-06-09 Renault 53
2020-04-17 Skoda 51
2020-05-12 Mercedes 51
2020-04-18 Land Rover 50
2020-04-17 Nissan 45
2020-04-17 Land Rover 44
2020-04-22 Renault 43
2020-04-17 Dacia 38
2020-06-08 Renault 38
2020-05-12 Jeep 36
2020-04-18 Chevrolet 35
2020-03-25 Hyundai 32
2020-06-12 Renault 32
2020-05-12 BMW 31
2020-06-14 Renault 31
2020-04-17 Honda 30
2020-06-03 Hyundai 30
2020-06-13 Renault 30
2020-05-20 BMW 29
2020-06-16 Honda 29
2020-04-17 Kia 28
2020-06-02 Renault 28
2020-06-11 Peugeot 28
2020-06-11 Renault 28
2020-06-15 Renault 28
2020-04-17 Citroen 27
2020-05-01 Renault 27
2020-04-17 Seat 26
2020-05-21 Land Rover 26
2020-05-27 BMW 25
2020-05-27 Audi 24
2020-05-12 Hyundai 23
2020-05-27 Mercedes 23
2020-04-09 Audi 22
2020-05-29 Renault 21
2020-06-12 Opel 21
2020-06-13 Opel 21
2020-06-16 Renault 21
2020-05-27 Jaguar 20
2020-04-08 Jeep 19
2020-05-12 Fiat 19
2020-05-17 Renault 19
2020-05-12 Land Rover 18
2020-06-09 Fiat 18
2020-06-10 Renault 18
2020-06-13 Volkswagen 18
2020-04-17 Chevrolet 17
2020-04-18 Porsche 17
2020-06-01 Renault 17
2020-06-11 Hyundai 17
2020-05-01 Mercedes 16
2020-06-13 Fiat 16
2020-06-15 Opel 16
2020-04-22 Peugeot 15
2020-05-12 Ford 15
2020-06-14 Hyundai 15
2020-06-15 Fiat 14
2020-04-22 Hyundai 13
2020-05-01 Opel 13
2020-05-12 Skoda 13
2020-06-05 Renault 13
2020-06-13 Hyundai 13
2020-04-22 Ford 12
2020-05-12 Audi 12
2020-05-12 Peugeot 12
2020-05-28 Renault 12
2020-06-03 Fiat 12
2020-06-03 Renault 12
2020-06-06 Renault 12
2020-06-08 Ford 12
2020-06-12 Hyundai 12
2020-06-15 Hyundai 12
2020-06-16 Opel 12
2020-04-18 Jeep 11
2020-04-22 Mercedes 11
2020-05-13 Renault 11
2020-05-22 Renault 11
2020-05-30 Renault 11
2020-06-05 Fiat 11
2020-06-09 Ford 11
2020-06-12 Fiat 11
2020-06-14 Opel 11
2020-03-24 Ford 10
2020-04-18 Mitsubishi 10
2020-05-01 BMW 10
2020-05-01 Fiat 10
2020-05-12 Nissan 10
2020-05-12 Opel 10
2020-05-17 Fiat 10
2020-05-17 Ford 10
2020-05-17 Hyundai 10
2020-06-09 Opel 10
2020-06-10 Opel 10
2020-06-11 Opel 10
2020-06-16 Fiat 10
2020-06-16 Ford 10
2020-04-22 Audi 9
2020-04-22 BMW 9
2020-04-22 Fiat 9
2020-04-29 Renault 9
2020-05-01 Peugeot 9
2020-05-10 Renault 9
2020-05-17 Audi 9
2020-05-19 Renault 9
2020-05-24 Renault 9
2020-06-07 Renault 9
2020-06-13 Ford 9
2020-06-14 Ford 9
2020-05-01 Audi 8
2020-05-01 Ford 8
2020-05-02 Renault 8
2020-05-05 Renault 8
2020-05-15 Fiat 8
2020-05-16 Renault 8
2020-05-17 Mercedes 8
2020-05-30 Ford 8
2020-06-02 Opel 8
2020-06-03 Ford 8
2020-06-05 Opel 8
2020-06-06 Opel 8
2020-06-09 Hyundai 8
2020-06-10 Hyundai 8
2020-06-11 Ford 8
2020-06-11 Tofas 8
2020-06-13 Tofas 8
2020-06-14 Fiat 8
2020-06-15 Ford 8
2020-03-25 Opel 7
2020-04-07 Opel 7
2020-04-17 Porsche 7
2020-05-06 Opel 7
2020-05-06 Renault 7
2020-05-27 Ford 7
2020-05-29 Ford 7
2020-06-01 Ford 7
2020-06-04 Renault 7
2020-06-06 Ford 7
2020-06-07 Hyundai 7
2020-06-09 Peugeot 7
2020-06-12 Honda 7
2020-06-14 Tofas 7
2020-06-16 Peugeot 7
2020-03-21 Ford 6
2020-04-02 Hyundai 6
2020-04-08 Opel 6
2020-04-18 Mazda 6
2020-04-22 Nissan 6
2020-04-27 Renault 6
2020-04-30 Fiat 6
2020-05-08 Renault 6
2020-05-09 Fiat 6
2020-05-09 Opel 6
2020-05-11 Renault 6
2020-05-16 Hyundai 6
2020-05-16 Opel 6
2020-05-17 Nissan 6
2020-05-18 Hyundai 6
2020-05-20 Renault 6
2020-05-28 BMW 6
2020-05-29 Fiat 6
2020-06-01 Audi 6
2020-06-01 Honda 6
2020-06-04 Opel 6
2020-06-05 Ford 6
2020-06-08 Fiat 6
2020-06-08 Opel 6
2020-06-10 Peugeot 6
2020-06-11 Fiat 6
2020-06-12 BMW 6
2020-06-12 Dacia 6
2020-06-13 BMW 6
2020-06-15 Tofas 6
2020-06-16 Hyundai 6
2020-03-20 Mercedes 5
2020-03-22 Opel 5
2020-03-25 Fiat 5
2020-03-26 Hyundai 5
2020-03-27 BMW 5
2020-04-01 Ford 5
2020-04-02 Fiat 5
2020-04-02 Ford 5
2020-04-07 Hyundai 5
2020-04-08 Ford 5
2020-04-10 Fiat 5
2020-04-10 Opel 5
2020-04-17 Jeep 5
2020-04-21 Fiat 5
2020-04-23 Renault 5
2020-05-01 Kia 5
2020-05-01 Land Rover 5
2020-05-03 Ford 5
2020-05-03 Opel 5
2020-05-03 Renault 5
2020-05-06 Ford 5
2020-05-07 Renault 5
2020-05-08 Fiat 5
2020-05-09 Renault 5
2020-05-11 Fiat 5
2020-05-12 Citroen 5
2020-05-12 Seat 5
2020-05-14 Renault 5
2020-05-14 Skoda 5
2020-05-15 Hyundai 5
2020-05-15 Renault 5
2020-05-16 Kia 5
2020-05-17 BMW 5
2020-05-17 Land Rover 5
2020-05-17 Opel 5
2020-05-17 Peugeot 5
2020-05-18 Opel 5
2020-05-18 Peugeot 5
2020-05-18 Renault 5
2020-05-21 Fiat 5
2020-05-25 Renault 5
2020-05-26 Fiat 5
2020-05-27 Renault 5
2020-05-28 Audi 5
2020-05-28 Hyundai 5
2020-05-29 Opel 5
2020-05-29 Skoda 5
2020-05-30 Audi 5
2020-05-30 Citroen 5
2020-06-01 Fiat 5
2020-06-03 Opel 5
2020-06-04 Ford 5
2020-06-05 Hyundai 5
2020-06-06 Fiat 5
2020-06-07 Ford 5
2020-06-08 Peugeot 5
2020-06-09 BMW 5
2020-06-10 Audi 5
2020-06-10 Fiat 5
2020-06-10 Ford 5
2020-06-10 Mercedes 5
2020-06-11 Honda 5
2020-06-12 Chevrolet 5
2020-06-12 Ford 5
2020-06-14 Mercedes 5
2020-06-14 Peugeot 5
2020-06-15 Audi 5
2020-06-15 BMW 5
2020-06-16 BMW 5
2020-03-19 Fiat 4
2020-03-25 Ford 4
2020-03-26 Ford 4
2020-03-27 Peugeot 4
2020-03-28 Kia 4
2020-03-29 Fiat 4
2020-04-01 Fiat 4
2020-04-01 Hyundai 4
2020-04-03 Opel 4
2020-04-04 Opel 4
2020-04-06 Opel 4
2020-04-08 Acura 4
2020-04-08 Fiat 4
2020-04-09 Ford 4
2020-04-13 BMW 4
2020-04-15 Acura 4
2020-04-16 Fiat 4
2020-04-18 Chrysler 4
2020-04-19 Renault 4
2020-04-20 Acura 4
2020-04-20 Renault 4
2020-04-21 Renault 4
2020-04-22 Land Rover 4
2020-04-22 Opel 4
2020-04-24 Fiat 4
2020-04-25 Fiat 4
2020-04-28 Opel 4
2020-04-29 Opel 4
2020-05-01 Hyundai 4
2020-05-01 Nissan 4
2020-05-01 Skoda 4
2020-05-02 Mercedes 4
2020-05-03 Fiat 4
2020-05-03 Hyundai 4
2020-05-05 Fiat 4
2020-05-07 Chevrolet 4
2020-05-07 Fiat 4
2020-05-08 Ford 4
2020-05-08 Opel 4
2020-05-11 Opel 4
2020-05-12 Dacia 4
2020-05-12 Honda 4
2020-05-13 Ford 4
2020-05-13 Hyundai 4
2020-05-14 Ford 4
2020-05-14 Hyundai 4
2020-05-14 Mercedes 4
2020-05-15 Opel 4
2020-05-16 BMW 4
2020-05-17 Skoda 4
2020-05-18 Citroen 4
2020-05-18 Dacia 4
2020-05-19 Fiat 4
2020-05-19 Opel 4
2020-05-19 Peugeot 4
2020-05-21 Ford 4
2020-05-23 Ford 4
2020-05-23 Opel 4
2020-05-28 Fiat 4
2020-05-28 Honda 4
2020-05-28 Opel 4
2020-05-29 Audi 4
2020-05-30 Honda 4
2020-05-30 Peugeot 4
2020-05-31 Fiat 4
2020-05-31 Hyundai 4
2020-05-31 Renault 4
2020-06-01 Hyundai 4
2020-06-01 Opel 4
2020-06-02 Fiat 4
2020-06-02 Ford 4
2020-06-02 Hyundai 4
2020-06-02 Kia 4
2020-06-03 Mercedes 4
2020-06-04 Chevrolet 4
2020-06-05 Nissan 4
2020-06-06 Hyundai 4
2020-06-06 Peugeot 4
2020-06-07 BMW 4
2020-06-07 Honda 4
2020-06-07 Opel 4
2020-06-08 Hyundai 4
2020-06-09 Dacia 4
2020-06-09 Nissan 4
2020-06-09 Tofas 4
2020-06-11 Skoda 4
2020-06-12 Audi 4
2020-06-12 Citroen 4
2020-06-12 Nissan 4
2020-06-12 Peugeot 4
2020-06-12 Skoda 4
2020-06-12 Tofas 4
2020-06-13 Honda 4
2020-06-13 Peugeot 4
2020-06-13 Skoda 4
2020-06-14 Chevrolet 4
2020-06-14 Skoda 4
2020-06-15 Nissan 4
2020-06-16 Citroen 4
2020-06-16 Dacia 4
2020-03-19 Ford 3
2020-03-21 Fiat 3
2020-03-23 Ford 3
2020-03-24 Fiat 3
2020-03-25 Peugeot 3
2020-03-26 Mercedes 3
2020-03-26 Opel 3
2020-03-27 Fiat 3
2020-03-27 Honda 3
2020-03-27 Hyundai 3
2020-03-27 Mercedes 3
2020-03-27 Opel 3
2020-03-28 Peugeot 3
2020-04-02 Opel 3
2020-04-02 Skoda 3
2020-04-03 Fiat 3
2020-04-04 Audi 3
2020-04-07 Fiat 3
2020-04-07 Ford 3
2020-04-09 Hyundai 3
2020-04-13 Honda 3
2020-04-14 Peugeot 3
2020-04-15 Ford 3
2020-04-16 Ford 3
2020-04-16 Opel 3
2020-04-18 Alfa Romeo 3
2020-04-18 Lada 3
2020-04-20 Opel 3
2020-04-22 Seat 3
2020-04-22 Skoda 3
2020-04-23 Ford 3
2020-04-24 Peugeot 3
2020-04-25 Ford 3
2020-04-25 Renault 3
2020-04-26 Renault 3
2020-04-28 Peugeot 3
2020-04-29 Fiat 3
2020-04-29 Peugeot 3
2020-04-30 Opel 3
2020-04-30 Porsche 3
2020-04-30 Renault 3
2020-05-01 Honda 3
2020-05-01 Seat 3
2020-05-02 Fiat 3
2020-05-03 Honda 3
2020-05-04 Ford 3
2020-05-04 Hyundai 3
2020-05-05 Ford 3
2020-05-05 Mercedes 3
2020-05-06 BMW 3
2020-05-07 Hyundai 3
2020-05-08 Hyundai 3
2020-05-08 Skoda 3
2020-05-09 Chevrolet 3
2020-05-09 Ford 3
2020-05-11 BMW 3
2020-05-11 Ford 3
2020-05-12 Kia 3
2020-05-12 Porsche 3
2020-05-13 Audi 3
2020-05-13 Mercedes 3
2020-05-14 Audi 3
2020-05-14 Honda 3
2020-05-17 Dacia 3
2020-05-17 Porsche 3
2020-05-18 Fiat 3
2020-05-20 Honda 3
2020-05-20 Opel 3
2020-05-21 Opel 3
2020-05-22 Dacia 3
2020-05-22 Fiat 3
2020-05-22 Hyundai 3
2020-05-23 Renault 3
2020-05-24 Hyundai 3
2020-05-24 Opel 3
2020-05-25 Hyundai 3
2020-05-26 Renault 3
2020-05-27 Fiat 3
2020-05-27 Opel 3
2020-05-27 Skoda 3
2020-05-28 Ford 3
2020-05-29 Hyundai 3
2020-05-29 Kia 3
2020-05-30 Hyundai 3
2020-05-30 Mercedes 3
2020-05-31 Honda 3
2020-05-31 Nissan 3
2020-05-31 Opel 3
2020-06-01 Citroen 3
2020-06-01 Peugeot 3
2020-06-01 Seat 3
2020-06-01 Skoda 3
2020-06-02 Chevrolet 3
2020-06-02 Citroen 3
2020-06-02 Honda 3
2020-06-02 Skoda 3
2020-06-03 Nissan 3
2020-06-04 Fiat 3
2020-06-04 Nissan 3
2020-06-06 Mercedes 3
2020-06-06 Seat 3
2020-06-07 Fiat 3
2020-06-07 Mercedes 3
2020-06-08 Nissan 3
2020-06-08 Skoda 3
2020-06-09 Mercedes 3
2020-06-11 Chevrolet 3
2020-06-11 Mercedes 3
2020-06-11 Seat 3
2020-06-12 Kia 3
2020-06-13 Dacia 3
2020-06-13 Mercedes 3
2020-06-13 Nissan 3
2020-06-14 Citroen 3
2020-06-14 Dacia 3
2020-06-14 Honda 3
2020-06-15 Skoda 3
2020-06-16 Mercedes 3
2020-06-16 Seat 3
2020-03-19 Dacia 2
2020-03-19 Honda 2
2020-03-19 Hyundai 2
2020-03-19 Mercedes 2
2020-03-19 Peugeot 2
2020-03-19 Seat 2
2020-03-20 BMW 2
2020-03-20 Chrysler 2
2020-03-20 Honda 2
2020-03-20 Hyundai 2
2020-03-21 Hyundai 2
2020-03-22 Audi 2
2020-03-22 Ford 2
2020-03-22 Nissan 2
2020-03-23 Fiat 2
2020-03-23 Hyundai 2
2020-03-23 Opel 2
2020-03-23 Peugeot 2
2020-03-24 Dacia 2
2020-03-24 Opel 2
2020-03-24 Peugeot 2
2020-03-25 Audi 2
2020-03-25 Nissan 2
2020-03-26 Fiat 2
2020-03-26 Peugeot 2
2020-03-28 Ford 2
2020-03-28 Opel 2
2020-03-29 Chevrolet 2
2020-03-29 Hyundai 2
2020-03-29 Opel 2
2020-03-30 Chevrolet 2
2020-03-30 Fiat 2
2020-03-30 Ford 2
2020-04-01 Audi 2
2020-04-01 BMW 2
2020-04-01 Kia 2
2020-04-01 Nissan 2
2020-04-01 Skoda 2
2020-04-02 Audi 2
2020-04-02 Citroen 2
2020-04-02 Mercedes 2
2020-04-03 Citroen 2
2020-04-03 Kia 2
2020-04-04 Peugeot 2
2020-04-05 Fiat 2
2020-04-05 Mercedes 2
2020-04-05 Opel 2
2020-04-06 Fiat 2
2020-04-06 Hyundai 2
2020-04-07 Dacia 2
2020-04-07 Honda 2
2020-04-07 Skoda 2
2020-04-08 BMW 2
2020-04-08 Hyundai 2
2020-04-08 Skoda 2
2020-04-09 Acura 2
2020-04-09 Fiat 2
2020-04-09 Mercedes 2
2020-04-10 BMW 2
2020-04-10 Ford 2
2020-04-10 Hyundai 2
2020-04-10 Mercedes 2
2020-04-11 Chevrolet 2
2020-04-11 Fiat 2
2020-04-11 Hyundai 2
2020-04-11 Opel 2
2020-04-12 Hyundai 2
2020-04-13 Fiat 2
2020-04-13 Ford 2
2020-04-13 Hyundai 2
2020-04-13 Nissan 2
2020-04-13 Opel 2
2020-04-14 Acura 2
2020-04-14 BMW 2
2020-04-15 Honda 2
2020-04-15 Hyundai 2
2020-04-15 Peugeot 2
2020-04-16 Honda 2
2020-04-16 Hyundai 2
2020-04-16 Mercedes 2
2020-04-16 Peugeot 2
2020-04-16 Skoda 2
2020-04-17 Alfa Romeo 2
2020-04-17 Infiniti 2
2020-04-17 Jaguar 2
2020-04-17 Mitsubishi 2
2020-04-18 Jaguar 2
2020-04-19 BMW 2
2020-04-19 Kia 2
2020-04-19 Nissan 2
2020-04-19 Opel 2
2020-04-20 Hyundai 2
2020-04-20 Jeep 2
2020-04-20 Skoda 2
2020-04-21 Ford 2
2020-04-21 Hyundai 2
2020-04-21 Land Rover 2
2020-04-21 Skoda 2
2020-04-22 Honda 2
2020-04-22 Kia 2
2020-04-23 Acura 2
2020-04-23 Citroen 2
2020-04-23 Fiat 2
2020-04-23 Hyundai 2
2020-04-24 BMW 2
2020-04-24 Ford 2
2020-04-24 Renault 2
2020-04-27 Acura 2
2020-04-27 Opel 2
2020-04-27 Peugeot 2
2020-04-28 Chevrolet 2
2020-04-28 Skoda 2
2020-04-29 Ford 2
2020-04-29 Hyundai 2
2020-04-30 Mercedes 2
2020-04-30 Seat 2
2020-04-30 Skoda 2
2020-05-01 Citroen 2
2020-05-01 Porsche 2
2020-05-02 BMW 2
2020-05-02 Dacia 2
2020-05-02 Ford 2
2020-05-02 Peugeot 2
2020-05-04 Fiat 2
2020-05-04 Peugeot 2
2020-05-04 Renault 2
2020-05-05 BMW 2
2020-05-05 Opel 2
2020-05-05 Peugeot 2
2020-05-06 Dacia 2
2020-05-06 Fiat 2
2020-05-06 Peugeot 2
2020-05-06 Skoda 2
2020-05-07 BMW 2
2020-05-07 Citroen 2
2020-05-07 Ford 2
2020-05-08 Mercedes 2
2020-05-09 Audi 2
2020-05-09 BMW 2
2020-05-09 Jeep 2
2020-05-11 Mercedes 2
2020-05-12 Alfa Romeo 2
2020-05-12 Chevrolet 2
2020-05-12 Jaguar 2
2020-05-12 Mazda 2
2020-05-13 Honda 2
2020-05-13 Opel 2
2020-05-13 Peugeot 2
2020-05-14 BMW 2
2020-05-14 Dacia 2
2020-05-14 Fiat 2
2020-05-15 Audi 2
2020-05-15 Ford 2
2020-05-15 Peugeot 2
2020-05-16 Chrysler 2
2020-05-16 Citroen 2
2020-05-16 Fiat 2
2020-05-16 Ford 2
2020-05-16 Mitsubishi 2
2020-05-16 Peugeot 2
2020-05-17 Seat 2
2020-05-18 Ford 2
2020-05-18 Honda 2
2020-05-18 Mercedes 2
2020-05-18 Skoda 2
2020-05-19 Ford 2
2020-05-19 Honda 2
2020-05-20 Citroen 2
2020-05-20 Fiat 2
2020-05-20 Mercedes 2
2020-05-21 Chevrolet 2
2020-05-21 Hyundai 2
2020-05-21 Renault 2
2020-05-22 Opel 2
2020-05-23 Audi 2
2020-05-23 Hyundai 2
2020-05-24 Nissan 2
2020-05-24 Peugeot 2
2020-05-25 Nissan 2
2020-05-26 Citroen 2
2020-05-26 Ford 2
2020-05-26 Honda 2
2020-05-26 Hyundai 2
2020-05-27 Honda 2
2020-05-27 Nissan 2
2020-05-27 Peugeot 2
2020-05-28 Nissan 2
2020-05-29 Acura 2
2020-05-29 BMW 2
2020-05-29 Mazda 2
2020-05-30 BMW 2
2020-05-31 Ford 2
2020-06-01 BMW 2
2020-06-01 Dacia 2
2020-06-01 Nissan 2
2020-06-02 Mercedes 2
2020-06-02 Mitsubishi 2
2020-06-02 Nissan 2
2020-06-02 Peugeot 2
2020-06-03 Citroen 2
2020-06-03 Dacia 2
2020-06-03 Peugeot 2
2020-06-03 Skoda 2
2020-06-04 BMW 2
2020-06-04 Dacia 2
2020-06-04 Honda 2
2020-06-04 Hyundai 2
2020-06-04 Mercedes 2
2020-06-04 Tofas 2
2020-06-05 Audi 2
2020-06-05 BMW 2
2020-06-05 Mercedes 2
2020-06-05 Tofas 2
2020-06-06 BMW 2
2020-06-06 Nissan 2
2020-06-06 Tofas 2
2020-06-07 Audi 2
2020-06-08 BMW 2
2020-06-08 Chevrolet 2
2020-06-08 Honda 2
2020-06-08 Mercedes 2
2020-06-09 Kia 2
2020-06-09 Mitsubishi 2
2020-06-10 BMW 2
2020-06-10 Honda 2
2020-06-10 Nissan 2
2020-06-11 Acura 2
2020-06-11 Dacia 2
2020-06-11 Nissan 2
2020-06-12 Mercedes 2
2020-06-13 Citroen 2
2020-06-13 Kia 2
2020-06-14 BMW 2
2020-06-14 Kia 2
2020-06-14 Mitsubishi 2
2020-06-14 Seat 2
2020-06-15 Chevrolet 2
2020-06-15 Dacia 2
2020-06-15 Peugeot 2
2020-06-16 Audi 2
2020-06-16 Nissan 2
2020-06-16 Skoda 2
2019-12-23 Hyundai 1
2019-12-24 Seat 1
2020-03-19 Audi 1
2020-03-19 BMW 1
2020-03-19 Chevrolet 1
2020-03-19 Citroen 1
2020-03-19 Opel 1
2020-03-20 Audi 1
2020-03-20 Chevrolet 1
2020-03-20 Fiat 1
2020-03-20 Ford 1
2020-03-20 Geely 1
2020-03-20 Opel 1
2020-03-20 Peugeot 1
2020-03-20 Skoda 1
2020-03-21 Audi 1
2020-03-21 BMW 1
2020-03-21 Chevrolet 1
2020-03-21 Dacia 1
2020-03-21 Honda 1
2020-03-21 Kia 1
2020-03-21 Nissan 1
2020-03-21 Opel 1
2020-03-21 Skoda 1
2020-03-22 Acura 1
2020-03-22 BMW 1
2020-03-22 Citroen 1
2020-03-22 Fiat 1
2020-03-22 Honda 1
2020-03-22 Hyundai 1
2020-03-22 Lada 1
2020-03-22 Peugeot 1
2020-03-22 Seat 1
2020-03-23 Audi 1
2020-03-23 Honda 1
2020-03-23 Seat 1
2020-03-24 Alfa Romeo 1
2020-03-24 BMW 1
2020-03-24 Citroen 1
2020-03-24 Hyundai 1
2020-03-24 Kia 1
2020-03-24 Land Rover 1
2020-03-25 BMW 1
2020-03-25 Honda 1
2020-03-25 Lada 1
2020-03-25 Mazda 1
2020-03-25 Mercedes 1
2020-03-25 Mitsubishi 1
2020-03-26 Acura 1
2020-03-26 Audi 1
2020-03-26 Citroen 1
2020-03-26 Honda 1
2020-03-26 Kia 1
2020-03-26 Land Rover 1
2020-03-27 Acura 1
2020-03-27 Audi 1
2020-03-27 Ford 1
2020-03-27 Kia 1
2020-03-27 Nissan 1
2020-03-28 Audi 1
2020-03-28 BMW 1
2020-03-28 Honda 1
2020-03-28 Land Rover 1
2020-03-28 Mercedes 1
2020-03-28 Nissan 1
2020-03-28 Seat 1
2020-03-28 Skoda 1
2020-03-29 Honda 1
2020-03-29 Mercedes 1
2020-03-29 Nissan 1
2020-03-30 Audi 1
2020-03-30 Hyundai 1
2020-03-30 Mercedes 1
2020-03-30 Opel 1
2020-03-30 Peugeot 1
2020-03-31 Fiat 1
2020-03-31 Ford 1
2020-03-31 Peugeot 1
2020-04-01 Acura 1
2020-04-01 Chevrolet 1
2020-04-01 Mercedes 1
2020-04-01 Opel 1
2020-04-01 Peugeot 1
2020-04-01 Seat 1
2020-04-02 Alfa Romeo 1
2020-04-02 Honda 1
2020-04-02 Jeep 1
2020-04-02 Kia 1
2020-04-02 Mazda 1
2020-04-02 Peugeot 1
2020-04-03 Acura 1
2020-04-03 BMW 1
2020-04-03 Chevrolet 1
2020-04-03 Dacia 1
2020-04-03 Ford 1
2020-04-03 Honda 1
2020-04-03 Land Rover 1
2020-04-03 Mazda 1
2020-04-03 Mitsubishi 1
2020-04-04 Fiat 1
2020-04-04 Honda 1
2020-04-04 Hyundai 1
2020-04-05 BMW 1
2020-04-05 Citroen 1
2020-04-05 Ford 1
2020-04-05 Hyundai 1
2020-04-05 Kia 1
2020-04-05 Nissan 1
2020-04-06 Acura 1
2020-04-06 BMW 1
2020-04-06 Chevrolet 1
2020-04-06 Ford 1
2020-04-06 Honda 1
2020-04-06 Peugeot 1
2020-04-06 Seat 1
2020-04-06 Skoda 1
2020-04-07 Chevrolet 1
2020-04-07 Lada 1
2020-04-07 Mercedes 1
2020-04-07 Peugeot 1
2020-04-07 Seat 1
2020-04-08 Chevrolet 1
2020-04-08 Honda 1
2020-04-08 Kia 1
2020-04-08 Land Rover 1
2020-04-08 Mercedes 1
2020-04-08 Peugeot 1
2020-04-08 Seat 1
2020-04-09 Dacia 1
2020-04-09 Kia 1
2020-04-09 Peugeot 1
2020-04-09 Skoda 1
2020-04-10 Audi 1
2020-04-10 Dacia 1
2020-04-10 Skoda 1
2020-04-11 BMW 1
2020-04-11 Ford 1
2020-04-11 Lada 1
2020-04-11 Mercedes 1
2020-04-11 Peugeot 1
2020-04-11 Seat 1
2020-04-11 Skoda 1
2020-04-12 Acura 1
2020-04-12 Chevrolet 1
2020-04-12 Fiat 1
2020-04-12 Honda 1
2020-04-12 Lada 1
2020-04-12 Mitsubishi 1
2020-04-12 Peugeot 1
2020-04-12 Skoda 1
2020-04-13 Citroen 1
2020-04-13 Kia 1
2020-04-13 Mercedes 1
2020-04-13 Peugeot 1
2020-04-13 Seat 1
2020-04-13 Skoda 1
2020-04-14 Audi 1
2020-04-14 Citroen 1
2020-04-14 Dacia 1
2020-04-14 Hyundai 1
2020-04-15 Fiat 1
2020-04-15 Mazda 1
2020-04-15 Mercedes 1
2020-04-16 Audi 1
2020-04-16 Dacia 1
2020-04-16 Kia 1
2020-04-17 Chrysler 1
2020-04-17 Lada 1
2020-04-17 Mazda 1
2020-04-19 Audi 1
2020-04-19 Fiat 1
2020-04-19 Honda 1
2020-04-19 Hyundai 1
2020-04-19 Skoda 1
2020-04-20 Audi 1
2020-04-20 BMW 1
2020-04-20 Citroen 1
2020-04-20 Ford 1
2020-04-20 Kia 1
2020-04-20 Peugeot 1
2020-04-21 Acura 1
2020-04-21 Citroen 1
2020-04-21 Opel 1
2020-04-21 Peugeot 1
2020-04-22 Chevrolet 1
2020-04-22 Citroen 1
2020-04-22 Dacia 1
2020-04-22 Jeep 1
2020-04-23 Audi 1
2020-04-23 BMW 1
2020-04-23 Chevrolet 1
2020-04-23 Dacia 1
2020-04-23 Land Rover 1
2020-04-23 Mercedes 1
2020-04-23 Nissan 1
2020-04-23 Opel 1
2020-04-24 Acura 1
2020-04-24 Audi 1
2020-04-24 Dacia 1
2020-04-24 Hyundai 1
2020-04-24 Land Rover 1
2020-04-24 Mazda 1
2020-04-24 Nissan 1
2020-04-24 Skoda 1
2020-04-25 Citroen 1
2020-04-25 Jeep 1
2020-04-25 Mercedes 1
2020-04-25 Nissan 1
2020-04-25 Opel 1
2020-04-25 Skoda 1
2020-04-26 Audi 1
2020-04-26 Chevrolet 1
2020-04-26 Citroen 1
2020-04-26 Fiat 1
2020-04-26 Ford 1
2020-04-26 Hyundai 1
2020-04-26 Opel 1
2020-04-26 Peugeot 1
2020-04-26 Seat 1
2020-04-27 Dacia 1
2020-04-27 Ford 1
2020-04-27 Honda 1
2020-04-27 Hyundai 1
2020-04-27 Land Rover 1
2020-04-27 Mercedes 1
2020-04-27 Seat 1
2020-04-27 Skoda 1
2020-04-28 BMW 1
2020-04-28 Citroen 1
2020-04-28 Honda 1
2020-04-28 Land Rover 1
2020-04-28 Renault 1
2020-04-28 Seat 1
2020-04-29 Dacia 1
2020-04-29 Mazda 1
2020-04-29 Skoda 1
2020-04-30 Chevrolet 1
2020-04-30 Ford 1
2020-04-30 Honda 1
2020-04-30 Hyundai 1
2020-04-30 Kia 1
2020-04-30 Nissan 1
2020-04-30 Peugeot 1
2020-05-01 Chevrolet 1
2020-05-01 Dacia 1
2020-05-01 Jeep 1
2020-05-02 Honda 1
2020-05-02 Hyundai 1
2020-05-02 Kia 1
2020-05-02 Opel 1
2020-05-02 Seat 1
2020-05-03 Land Rover 1
2020-05-03 Skoda 1
2020-05-04 BMW 1
2020-05-04 Dacia 1
2020-05-04 Honda 1
2020-05-04 Kia 1
2020-05-04 Land Rover 1
2020-05-04 Nissan 1
2020-05-04 Opel 1
2020-05-04 Skoda 1
2020-05-05 Audi 1
2020-05-05 Chevrolet 1
2020-05-05 Dacia 1
2020-05-05 Honda 1
2020-05-05 Hyundai 1
2020-05-05 Skoda 1
2020-05-06 Chevrolet 1
2020-05-06 Chrysler 1
2020-05-06 Honda 1
2020-05-06 Hyundai 1
2020-05-06 Mercedes 1
2020-05-06 Seat 1
2020-05-07 Acura 1
2020-05-07 Honda 1
2020-05-07 Jaguar 1
2020-05-07 Land Rover 1
2020-05-07 Peugeot 1
2020-05-07 Skoda 1
2020-05-08 Acura 1
2020-05-08 Audi 1
2020-05-08 Dacia 1
2020-05-08 Peugeot 1
2020-05-08 Seat 1
2020-05-09 Citroen 1
2020-05-09 Honda 1
2020-05-09 Hyundai 1
2020-05-09 Kia 1
2020-05-09 Mercedes 1
2020-05-09 Nissan 1
2020-05-09 Peugeot 1
2020-05-09 Skoda 1
2020-05-10 BMW 1
2020-05-10 Citroen 1
2020-05-10 Fiat 1
2020-05-10 Ford 1
2020-05-10 Honda 1
2020-05-10 Infiniti 1
2020-05-10 Mazda 1
2020-05-10 Mercedes 1
2020-05-10 Nissan 1
2020-05-10 Opel 1
2020-05-10 Porsche 1
2020-05-10 Skoda 1
2020-05-11 Audi 1
2020-05-11 Chevrolet 1
2020-05-11 Honda 1
2020-05-11 Hyundai 1
2020-05-11 Kia 1
2020-05-11 Mitsubishi 1
2020-05-11 Nissan 1
2020-05-11 Peugeot 1
2020-05-11 Skoda 1
2020-05-12 Mitsubishi 1
2020-05-13 BMW 1
2020-05-13 Chevrolet 1
2020-05-13 Dacia 1
2020-05-13 Fiat 1
2020-05-13 Geely 1
2020-05-13 Kia 1
2020-05-13 Land Rover 1
2020-05-13 Rover 1
2020-05-13 Seat 1
2020-05-13 Skoda 1
2020-05-14 Citroen 1
2020-05-14 Opel 1
2020-05-14 Peugeot 1
2020-05-15 Chevrolet 1
2020-05-15 Citroen 1
2020-05-15 Honda 1
2020-05-15 Kia 1
2020-05-15 Mazda 1
2020-05-15 Mercedes 1
2020-05-15 Seat 1
2020-05-15 Skoda 1
2020-05-16 Audi 1
2020-05-16 Chevrolet 1
2020-05-16 Mercedes 1
2020-05-16 Seat 1
2020-05-17 Alfa Romeo 1
2020-05-17 Chrysler 1
2020-05-17 Honda 1
2020-05-17 Kia 1
2020-05-18 BMW 1
2020-05-18 Seat 1
2020-05-19 BMW 1
2020-05-19 Chevrolet 1
2020-05-19 Hyundai 1
2020-05-19 Skoda 1
2020-05-20 Chevrolet 1
2020-05-20 Dacia 1
2020-05-20 Hyundai 1
2020-05-20 Kia 1
2020-05-20 Peugeot 1
2020-05-20 Seat 1
2020-05-20 Skoda 1
2020-05-21 Audi 1
2020-05-21 Citroen 1
2020-05-21 Dacia 1
2020-05-21 Mercedes 1
2020-05-21 Peugeot 1
2020-05-21 Skoda 1
2020-05-22 BMW 1
2020-05-22 Chevrolet 1
2020-05-22 Ford 1
2020-05-22 Honda 1
2020-05-22 Kia 1
2020-05-22 Land Rover 1
2020-05-22 Mercedes 1
2020-05-22 Skoda 1
2020-05-23 Dacia 1
2020-05-23 Fiat 1
2020-05-23 Honda 1
2020-05-23 Kia 1
2020-05-23 Peugeot 1
2020-05-23 Seat 1
2020-05-24 Acura 1
2020-05-24 BMW 1
2020-05-24 Chevrolet 1
2020-05-24 Citroen 1
2020-05-24 Fiat 1
2020-05-24 Lada 1
2020-05-25 Audi 1
2020-05-25 BMW 1
2020-05-25 Fiat 1
2020-05-25 Honda 1
2020-05-25 Kia 1
2020-05-25 Lada 1
2020-05-25 Mercedes 1
2020-05-25 Opel 1
2020-05-25 Peugeot 1
2020-05-26 Audi 1
2020-05-26 BMW 1
2020-05-26 Kia 1
2020-05-27 Kia 1
2020-05-27 Porsche 1
2020-05-27 Rover 1
2020-05-28 Alfa Romeo 1
2020-05-28 Chevrolet 1
2020-05-28 Citroen 1
2020-05-28 Dacia 1
2020-05-28 Land Rover 1
2020-05-28 Porsche 1
2020-05-28 Seat 1
2020-05-28 Skoda 1
2020-05-29 Citroen 1
2020-05-29 Honda 1
2020-05-29 Mercedes 1
2020-05-29 Nissan 1
2020-05-30 Dacia 1
2020-05-30 Fiat 1
2020-05-30 Lada 1
2020-05-30 Nissan 1
2020-05-30 Opel 1
2020-05-30 Seat 1
2020-05-31 Alfa Romeo 1
2020-05-31 BMW 1
2020-05-31 Chevrolet 1
2020-05-31 Dacia 1
2020-05-31 Mitsubishi 1
2020-05-31 Peugeot 1
2020-06-01 Chevrolet 1
2020-06-02 Acura 1
2020-06-02 Dacia 1
2020-06-02 Lada 1
2020-06-02 Seat 1
2020-06-03 Acura 1
2020-06-03 Audi 1
2020-06-03 BMW 1
2020-06-03 Mazda 1
2020-06-03 Seat 1
2020-06-04 Acura 1
2020-06-04 Citroen 1
2020-06-04 Kia 1
2020-06-05 Chevrolet 1
2020-06-05 Citroen 1
2020-06-05 Dacia 1
2020-06-05 Honda 1
2020-06-05 Kia 1
2020-06-05 Peugeot 1
2020-06-05 Seat 1
2020-06-06 Audi 1
2020-06-06 Chevrolet 1
2020-06-06 Citroen 1
2020-06-06 Dacia 1
2020-06-06 Honda 1
2020-06-06 Rover 1
2020-06-06 Skoda 1
2020-06-07 Citroen 1
2020-06-07 Dacia 1
2020-06-07 Kia 1
2020-06-07 Peugeot 1
2020-06-07 Skoda 1
2020-06-07 Tofas 1
2020-06-08 Audi 1
2020-06-08 Dacia 1
2020-06-08 Land Rover 1
2020-06-08 Mitsubishi 1
2020-06-09 Audi 1
2020-06-09 Chevrolet 1
2020-06-09 Citroen 1
2020-06-09 Honda 1
2020-06-09 Lada 1
2020-06-09 Skoda 1
2020-06-10 Chevrolet 1
2020-06-10 Citroen 1
2020-06-10 Jeep 1
2020-06-10 Kia 1
2020-06-10 Seat 1
2020-06-11 Audi 1
2020-06-11 BMW 1
2020-06-11 Citroen 1
2020-06-11 Jaguar 1
2020-06-12 Jeep 1
2020-06-12 Lada 1
2020-06-12 Mitsubishi 1
2020-06-12 Porsche 1
2020-06-12 Seat 1
2020-06-13 Audi 1
2020-06-13 Jeep 1
2020-06-13 Seat 1
2020-06-14 Acura 1
2020-06-14 Audi 1
2020-06-14 Land Rover 1
2020-06-14 Mazda 1
2020-06-14 Nissan 1
2020-06-15 Alfa Romeo 1
2020-06-15 Citroen 1
2020-06-15 Honda 1
2020-06-15 Kia 1
2020-06-15 Lada 1
2020-06-15 Mazda 1
2020-06-15 Mercedes 1
2020-06-15 Seat 1
2020-06-16 Acura 1
2020-06-16 Alfa Romeo 1
2020-06-16 Jeep 1
2020-06-16 Tofas 1

Renault is been in advertisements more than 6 times of the next brand. The reasons of this situation can be listed like below:

  1. The data may not be collected randomly. (We don’t have any information about the collection of the sample. Maybe, there was a sample selection bias, that the data is sorted with respect to a feature and selected the top 9044 rows of them or this data is collected from only one platform and other platforms are discarded. Also, there are some popular car companies in Turkey market but they are not in the dataset like Toyota, this can be the sign of the sample selection bias. But, to be able to make an analysis, we will assume that this process is done randomly.)
  2. In the internet advertisements, Renault is the most appealing brand among others due to strategies of companies of brands (which also we should assume that there is no possibility like that)
  3. Prices of Renault’s car can be affordable respect to other cars of brands because of high price increase in taxes.
  4. Renault is the most popular Brand in online Turkey market because the company produces cars for diverse segments of consumers which helps to reach higher number of sales.
carmarket_brand = carmarket %>%
  group_by(Brand) %>%
  summarise(count = n(), min_price = min(Price), max_price = max(Price), avg_price = mean(Price), median_price = median(Price))

carmarket_brand  %>%
  arrange(desc(count)) %>%
  select(Brand, count)%>%
  kable(col.names = c("Brand", "Count")) %>%
  kable_styling("striped", full_width = T) %>%
  scroll_box(width = "100%", height = "400px")
Brand Count
Renault 2079
Fiat 653
Opel 643
Hyundai 638
Ford 601
BMW 598
Mercedes 542
Audi 425
Peugeot 421
Dacia 323
Honda 261
Skoda 259
Nissan 229
Citroen 199
Land Rover 171
Kia 164
Seat 150
Chevrolet 125
Jeep 83
Tofas 45
Acura 41
Porsche 39
Jaguar 28
Mitsubishi 28
Mazda 22
Volkswagen 18
Lada 16
Alfa Romeo 14
Chrysler 11
Infiniti 3
Rover 3
Geely 2

The number of advertisement belong to different car brands are given above table.

carmarket_brand %>%
  arrange(avg_price)%>%
  select(Brand, avg_price, median_price, min_price, max_price) %>%
  kable(col.names = c("Brand", "Average Price", "Median Price", "Minimum Price", "Maximum Price"))%>% 
  kable_styling("striped", full_width = T) %>%
  scroll_box(width = "100%", height = "400px")
Brand Average Price Median Price Minimum Price Maximum Price
Tofas 17234.44 16500.0 10500 28500
Lada 22143.75 13125.0 5500 119900
Rover 24666.67 24000.0 21000 29000
Geely 43250.00 43250.0 35000 51500
Mazda 66086.36 38675.0 11900 179750
Fiat 68145.62 65900.0 12345 169500
Mitsubishi 73462.50 69850.0 23000 187950
Citroen 79485.17 72500.0 13750 281850
Dacia 81834.67 72500.0 21000 170000
Renault 85985.26 81650.0 9500 300000
Opel 88746.34 82000.0 16000 300000
Chevrolet 89637.99 70000.0 30500 900000
Hyundai 90242.06 84900.0 14750 318000
Ford 94712.37 90000.0 6250 339000
Chrysler 95400.00 96500.0 35000 169500
Honda 106317.52 93000.0 10000 289000
Peugeot 107926.51 82900.0 12750 334000
Alfa Romeo 118064.29 106950.0 32000 343250
Kia 118527.12 122250.0 16500 240000
Seat 121214.98 119000.0 24900 345000
Volkswagen 123500.00 123500.0 123500 123500
Acura 124303.66 148750.0 19750 345000
Skoda 128163.50 131500.0 9900 320000
Nissan 131742.66 127000.0 11111 315000
Infiniti 136966.67 122500.0 78500 209900
Jeep 201382.41 133000.0 42250 457500
Audi 243041.13 191950.0 15000 2550000
Mercedes 290055.56 228874.5 13500 2720000
BMW 294612.95 249000.0 23000 1715000
Jaguar 538166.07 634500.0 54500 634500
Land Rover 604241.52 444500.0 43500 2425000
Porsche 968731.79 779990.0 159500 2375000

When we examine these two tables, we see that there are cheaper cars in the dataset. So, the third option is not true. So, we can assume that Renault is one of the online market leaders in the Turkey market. For the diversity of segments, we need too plot the prices of Renault.

carmarket[Brand == 'Renault', .(Price)] %>%
  ggplot(., aes(y = Price)) +
  geom_boxplot() +
  theme_minimal() +
  expand_limits(x=c(-0.5,0.5)) +
  labs(title = "Price Diversity of Renault",
       subtitle = st,
       y = "Price") +
  scale_y_continuous(labels = comma)

We can see from the plot that Renault has cars for every segment in Turkey market. This could make them to be very popular in the market.

2.2 Price Analysis of Car Brands

In the data set, the each car its own price, and these various price can be classified by using price intervals. By using quantile, we divide price variable into five level and then, we sort from the Very Low to the Very High. And we create another variable for this data set, which is called Price Group. After that, by using this classification, cars are examined with their price groups.

quant = quantile(carmarket$Price, seq(0, 1, 0.2))

carmarket_price_group <- carmarket %>%
  mutate(price_group = case_when(
    Price < quant[2] ~ "Very Low",
    Price < quant[3] ~ "Low",
    Price < quant[4] ~ "Medium",
    Price < quant[5] ~ "High",
    TRUE ~ "Very High"
  )) %>%
  mutate(price_group = factor(price_group, levels = c("Very Low", "Low", "Medium", "High", "Very High")))

carmarket_price_group %>%
  group_by(Brand, price_group) %>%
  summarize(counter = n()) %>%
  mutate(percentage = 100 * counter / sum(counter)) %>%
  ggplot(., aes(x = '', y = counter, fill = price_group)) + 
  geom_bar(width = 1, stat = "identity", position = "fill") +
  coord_polar("y") +
  theme_void() +
  theme(plot.title = element_text(vjust = 0.5)) +
  facet_wrap(~Brand) +
  labs(title = "Price Group Analyses of Car Brand",
       subtitle = st,
       fill = "Price Group")

By using Price Group classification, we can obtain spread of the price in each car brand. Geely, and Tofas, for example, have only very low price, whereas the Maserati’s price is in the very high class. Moreover, Jaguar and Porsche are almost in the very high class. The others have different price interval.

To give more understandable analysis for the price of the brands, the following table can be used. This table illustrates the minimum, maximum and average prices of the cars according to the brands.

carmarket %>%
  group_by(Brand) %>%
  summarize(MinPrice = min(Price),
            Average_Price = round(mean(Price)),
            MaxPrice = max(Price)) %>%
  select(Brand,MinPrice, Average_Price,MaxPrice) %>%
  arrange(desc(Average_Price)) %>%
  head(10) %>%
  kable(col.names = c("Brand",  "Minimum Price", "Average Price", "Maximum Price")) %>%
  kable_styling("striped", full_width = T) %>%
  scroll_box(width = "100%", height = "400px")
Brand Minimum Price Average Price Maximum Price
Porsche 159500 968732 2375000
Land Rover 43500 604242 2425000
Jaguar 54500 538166 634500
BMW 23000 294613 1715000
Mercedes 13500 290056 2720000
Audi 15000 243041 2550000
Jeep 42250 201382 457500
Infiniti 78500 136967 209900
Nissan 11111 131743 315000
Skoda 9900 128163 320000

The Brands are sorted according to the average price. In the first place, there is Porsche. This results also support the price group analysis. Moreover, to provide more understandable interpretation for the Brand, we present the bar chart of the Brands according to the their average price.

carmarket %>%
  group_by(Brand) %>%
  summarise(Average_Price = mean(Price)) %>%
  arrange(desc(Average_Price))%>%
  
  ggplot(., aes(y=reorder(Brand,Average_Price), x = Average_Price, fill = Brand)) +
    geom_col() +
    theme_minimal() +
    labs(title = "Order of the Car Brand According to \nTheir Average Price",
         subtitle = st,
         x = "Average Price",
         y = "Brands")

2.3 Price Analysis By Body Type

In the previous section, we analyze the car brands and their features like Price. In this section we present the body type of the cars. One important factor that impacts this decision is the type of car body which refers to the shape and the model.

carmarket %>%
  group_by(Body_Type) %>%
  summarize(Average_Price = mean(Price)) %>%
  
  ggplot(.,aes(x=reorder(Body_Type, -Average_Price), y = Average_Price, color= Body_Type)) +
    geom_point(size=7) +
    geom_segment(aes(x=Body_Type,
                     xend=Body_Type,
                     y=0,
                     yend=Average_Price))+
    theme_minimal() +
    scale_y_continuous(labels = function(x) format(x, scientific = FALSE)) +
    theme(axis.text.x = element_text(angle = 90), legend.position = "none")+
        labs(title = "Average Price According to the Body Type",
         subtitle = st, 
         x = "Body Type",
         y = "Average Price",
         Fill = "Body Type")

In the first place, there is sport/coupe body type because of the high average price of these cars. The reason behind this idea is that, the most of luxury cars with high price are sport cars such as Porsche.

2.4 Price Analysis By Fuel Type

The fuel of the cars can be varied. There are for different fuel type: (i) diesel, (ii) electricity, (iii) gasoline, and (iv) hybrid. While diesel is produced by the distillation of crude oil, Gasoline is obtained from crude oil and other petroleum liquids. Hybrids, on the other hand, is the combination of the gasoline and electrical.

carmarket %>%
  group_by(Fuel_Type) %>%
  summarise(count = n()) %>%
  mutate(percentage = 100*round(count/sum(count),3)) %>%
  
  ggplot(., aes(x = '', y = count, fill = Fuel_Type)) + 
  geom_bar(width = 1, stat = "identity") +
  coord_polar("y") +
  theme_void()+
  theme(plot.title = element_text(vjust = 0.5)) +
  geom_text(aes(label = paste(format(percentage,digits=2), "%")), size=4, position = position_stack(vjust = 0.5)) +
  labs(title = "Percentages of Fuel Types",
       subtitle = st,
       fill = "Fuel Types")

The pie chart shows that, the most of the cars in this dataset use Diesel, whereas the Hybrid usage is very low. These different fuel types can affect the price of the cars. To examine this assumption, we calculate minimum, maximum, and average price that are given below according to the fuel type.

carmarket %>%
  group_by(Fuel_Type) %>%
  summarize(count = n(),
            Min_Price = min(Price),
            Average_Price = mean(Price),
            Max_Price = max(Price)) %>%
  mutate(percentage = 100*round(count/sum(count),3))%>%
  arrange(desc(Average_Price)) %>%
  select(Fuel_Type, count,  percentage, Min_Price, Average_Price, Max_Price ) %>%
  kable(col.names = c("Fuel Type", "Number of Ad.", "Percentage", "Minimum Price", "Average Price", "Maximum Price"))  %>%
  kable_minimal(full_width = F)
Fuel Type Number of Ad. Percentage Minimum Price Average Price Maximum Price
Hybrid 27 0.3 126900 892905.56 2375000
Electricity 1348 15.3 10000 191744.10 2550000
Diesel 5812 65.8 11000 149461.04 2720000
Gasoline 1647 18.6 5500 58290.84 293000

When we consider the table, the order of the fuel types according to the average price from the lowest to highest is Gasoline, Diesel, Electricity, and Hybrid. Moreover, the spread of price according to the fuel types is illustrated as box plot below.

carmarket %>%
  group_by(Fuel_Type) %>%

  ggplot(.,aes(x=Fuel_Type, y = Price, fill= Fuel_Type)) +
    geom_boxplot() +
    theme_minimal() +
    scale_y_continuous(labels = function(x) format(x, scientific = FALSE)) +
    labs(title = "Prices According to the Fuel Type",
         subtitle = st, 
         x = "Fuel Type",
         y = "Price",
         fill = "Fuel Type")

  • There are many outliers in Diesel and Electricity Fuel Type.
  • Gasoline is the least expensive fuel type, on the other hand, hybrid is the most expensive one.
  • The median of the Fuel Types, which are Diesel, Electricity, and Gasoline, almost in the middle of the quantiles. However, the median Hybrid is very close to the first quantile.
  • Moreover, since the price interval of the Hybrid is wider, there is no outlier data.

2.5 Price Analysis By Gear

Like the fuel type, there is another feature, Gear Type, which affects the selection of cars. For this, we search the relationship between price and gear type.

carmarket %>%
  ggplot(., aes(x = Gear, y = Price, color = Gear)) +
  geom_jitter() +
  theme_minimal() +
  scale_y_continuous(labels = function(x) format(x, scientific = FALSE)) +
    labs(title = " Price According to the Gear Type",
         x = "Gear Type",
         y = "Price",
         color = "Gear Type")

The half of the cars in this data set belongs to the Manual Gear Type. However, price distribution in manual gear type concentrates in a narrow area. Semi automatic and automatic, on the other hand, have a wider area with possible outliers.

carmarket %>%
  group_by(Gear) %>%
  summarize(count=n(),Min_Price=min(Price),Average_Price = mean(Price),Max_Price=max(Price) ) %>%
  mutate(percentage = 100*round(count/sum(count),3))%>%
  arrange(desc(percentage)) %>%
  select(Gear, count,  percentage, Min_Price, Average_Price, Max_Price ) %>%
  kable(col.names = c("Gear","Number of Ad","Percentage",  "Minimum Price", "Average Price", "Maximum Price")) %>%
  kable_minimal(full_width = F)
Gear Number of Ad Percentage Minimum Price Average Price Maximum Price
Manual 4462 50.5 5500 68453.65 300000
Automatic 2325 26.3 10000 240026.97 2720000
Semi Automatic 2047 23.2 36000 187469.05 1550000

We give gear type branching according to the car brands below.

carmarket %>%
  group_by(Brand, Gear) %>%
  summarize(gear_type_count = n())  %>%
  mutate(gear_type_percentage = 100*round(gear_type_count / sum(gear_type_count), digits = 3)) %>%
  select(Brand, Gear, gear_type_percentage) %>%
  pivot_wider(id_cols = Brand, names_from = Gear, values_from = gear_type_percentage) %>%
  kable(col.names = c("Brand", "Automatic (%)", "Manual (%)", "Semi Automatic (%)"))%>%
  kable_styling("striped", full_width = T) %>%
  scroll_box(width = "100%", height = "400px")
Brand Automatic (%) Manual (%) Semi Automatic (%)
Acura 48.8 46.3 4.9
Alfa Romeo 35.7 42.9 21.4
Audi 33.2 3.5 63.3
BMW 50.8 7.5 41.6
Chevrolet 39.2 52.0 8.8
Chrysler 100.0 NA NA
Citroen 13.6 71.4 15.1
Dacia 0.9 96.9 2.2
Fiat 4.3 84.1 11.6
Ford 13.3 69.2 17.5
Geely NA 100.0 NA
Honda 52.5 33.0 14.6
Hyundai 32.1 53.3 14.6
Infiniti 66.7 NA 33.3
Jaguar 92.9 3.6 3.6
Jeep 92.8 7.2 NA
Kia 53.0 31.1 15.9
Lada NA 100.0 NA
Land Rover 74.3 1.2 24.6
Mazda 50.0 50.0 NA
Mercedes 57.9 12.7 29.3
Mitsubishi 14.3 78.6 7.1
Nissan 38.4 41.5 20.1
Opel 34.8 57.9 7.3
Peugeot 31.1 57.0 11.9
Porsche 51.3 NA 48.7
Renault 6.5 67.2 26.3
Rover 33.3 66.7 NA
Seat 10.0 37.3 52.7
Skoda 13.1 30.5 56.4
Tofas NA 100.0 NA
Volkswagen 100.0 NA NA

2.6 Price Analysis with Gear and Fuel Type

Up until now, we examine relationship between a variable with price. In this subsection, we address relationship between price and more than one variable, i.e., Gear and Fuel Type.

carmarket %>%
  group_by(Fuel_Type, Gear) %>%
  summarise(Average_Price = mean(Price)) %>%
  
  ggplot(.,aes(x=reorder(Fuel_Type, -Average_Price), y = Average_Price, fill= Fuel_Type)) +
    geom_col() +
    facet_wrap(~Gear) +
    theme_minimal() +
    theme(axis.text.x = element_text(angle = 90), legend.position = "none") +
    scale_y_continuous(labels = function(x) format(x, scientific = FALSE)) +
    labs(title = "Average Price According to the Fuel Type for Different Gear Type",
         subtitle = st, 
         x = "Fuel Type",
         y = "Average Price",
         Fill = "Fuel Type")

According to the results,

  • The most expensive cars are located in Semi-Automatic and Automatic Gear Type with Hybrid Fuel Type.
  • While the Hybrid Fuel Type is more recent technology, there are no cars in Manual Gear Type.
  • The least expensive cars are located in Gasoline Fuel type in all Gear Types.

2.7 Price Analysis By CCM

The CCM is also important to predict car price, for this reason before to create linear regression model, we want to analyze relationship between Price and CCM.

carmarket%>% 
  group_by(CCM)%>% 
  ggplot(., aes(x=CCM, y=Price, fill=CCM))+
  geom_boxplot()+
  theme_minimal()+
  scale_y_continuous(labels = function(x) format(x, scientific = FALSE)) +
  scale_y_log10()+
  theme(axis.text.x = element_text(angle = 90), legend.position = "none")+
    labs(title = "Average Price According to CCM",
         subtitle = st, 
         x = "CCM",
         y = "Price",
         Fill = "CCM")

2.8 Price Analysis By HP and Seller Status

Horsepower is a unit of power used to measure the forcefulness of a car’s engine.We want to analyze relationship between Price and Horse Power by using Seller Status.

carmarket %>%
  group_by(Horse_Power, Seller_Status) %>%
  summarize(mean_price = mean(Price)) %>%
  
  ggplot(., aes(y=mean_price, x = Horse_Power, fill = Horse_Power)) +
  geom_col() +
  facet_wrap(~Seller_Status) +
  theme_minimal() +
  theme(legend.position = "none") +
  scale_y_continuous(labels = function(x) format(x, scientific = FALSE)) +
  theme(axis.text.x = element_text(angle = 90), legend.position = "none")+
  labs(title = "Average Price According to the Horse Power",
       subtitle = st, 
       x = "Average Price",
       y = "Horse Power")

carmarket %>%
  group_by(Horse_Power) %>%
  summarize(count=n(),
            Average_Price = mean(Price)) %>%
  mutate(percentage = 100*round(count/sum(count),3))%>%
  arrange(desc(percentage)) %>%
  select(Horse_Power, count,  percentage, Average_Price ) %>%
  kable(col.names = c("Horse Power","Number of Ad","Percentage", "Average Price")) %>%
  kable_minimal(full_width = F)
Horse Power Number of Ad Percentage Average Price
100 HP and below 5440 61.6 97748.33
101-125 HP 1315 14.9 119633.04
126-150 HP 892 10.1 171425.86
151-175 HP 484 5.5 256803.36
176-200 HP 267 3.0 410941.04
276-300 HP 202 2.3 294607.92
201-225 HP 70 0.8 387050.70
226-250 HP 68 0.8 603539.56
251-275 HP 70 0.8 485320.71
301-325 HP 19 0.2 374136.84
326-350 HP 4 0.0 593475.00
376-400 HP 1 0.0 56750.00
451-475 HP 1 0.0 41000.00
601 HP and above 1 0.0 60000.00
  • There are no car advertisement with more than 200 Horse Power in Classic and Damaged Seller Status.
  • Although there are some car advertisements in 2nd Hand Seller Status, the majority is in 0 Km.
  • While the 2nd Hand cars category has almost all Horse Power Types, O Km cars category does not contain Horse Power over 325 HP.

2.9 Seller and Seller Status Relationship

In this online car market data set, there are various sellers and these sellers present different car status such as 0 km, 2nd Hand, Classic, and Damaged. To see how many status takes place in different seller, we create this subsection.

carmarket %>%
  group_by(Seller,Seller_Status) %>%
  summarise(count=n()) %>%
  mutate(percentage = 100*count/sum(count)) %>%

  
  ggplot(., aes(x = '', y = count, fill = Seller_Status)) +
  geom_bar(width = 1, stat = "identity", position = "fill") +
  coord_polar("y") +
  theme_void() +
  theme(plot.title = element_text(vjust = 0.5)) +
  facet_wrap(~Seller) +
  labs(title = "Seller Status Distribution of Sellers",
       subtitle = st,
       fill = "Seller Status")

  • Gallery and Owner mostly sell 2nd Hand cars, whereas Authority sell 0 km cars.
  • There are no seller status, which are Classic and Damaged in the Authority Seller.
carmarket %>%
  group_by(Seller,Seller_Status) %>%
  summarise(count=n()) %>%
  mutate(percentage = 100*round(count/sum(count), digits = 3))%>%
  select(Seller, Seller_Status, count, percentage)%>%
  kable(col.names = c("Seller", "Seller Status", "Count", "Percentage")) %>%
  kable_minimal(full_width = F)
Seller Seller Status Count Percentage
Authority 0 km 63 94.0
Authority 2nd Hand 4 6.0
Galery 0 km 159 2.2
Galery 2nd Hand 6957 97.3
Galery Classic 3 0.0
Galery Damaged 33 0.5
Owner 0 km 12 0.7
Owner 2nd Hand 1590 98.5
Owner Classic 7 0.4
Owner Damaged 6 0.4

To provide clear numerical information about Seller and Seller Status, we also give the number and percentage advertisements according to the Seller and Seller Status.

2.10 Gear and Brand Relationship

In this part, we give the relationship between Gear Type and Brand.

carmarket %>%
  group_by(Brand, Gear) %>%
  summarize(gear_type_count = n())  %>%
  mutate(gear_type_percentage = gear_type_count / sum(gear_type_count)) %>%
  #head(108) %>%
  ggplot(., aes(x = Brand, y = gear_type_count, fill = Gear)) +
  geom_bar(position = "fill",stat = "identity") +
  theme_minimal() +
  scale_y_continuous(labels = scales::percent_format()) +
  #geom_text(aes(label = format(gear_type_percentage, digits=3)), size=4, position = position_dodge(0.9)) +
  theme(axis.text.x = element_text(angle = 90), legend.position = "right") +
  labs(title = "Gear Type Comparison of Car Brands",
       subtitle = st,
       x = "Brand",
       y = "Percentage of Gear Type", 
       fill = "Gear Type")

The results show that,

  • The all cars of the Chyrsler and Volkswagen have only automatic gear type, in the 2020 online car market.
  • Geely, Lada, and Tofas have only manual gear type.
  • The other car brands have various gear type in their cars.

3. Conclusion

In this Exploratory Data Analysis we investigate the 2020 online car market data in Turkey. The main purpose of this study is to find the relationship between features and Price of the cars. Each car has different properties, for example body type, gear type, color, etc. These properties affect both the Price and the demand of car market in Turkey. For this reason, before conducting models for forecasting car price, first, variables and their sub-groups are analyzed. Then, graphical visualizations are introduced to present more understandable information about dataset. In the next section, some models to forecast price of cars will be addressed.