Ikea Furniture

Setting up R Packages

library(tidyverse)
library(mosaic)
library(skimr)
library(ggformula)
library(ggridges)

Plot Theme and Fonts

```{r}
#| code-fold: true
#| message: false
#| warning: false

knitr::opts_chunk$set(
  fig.width = 7,
  fig.asp = 0.618, # Golden Ratio
  # out.width = "80%",
  fig.align = "center"
)
##
## https://stackoverflow.com/questions/36476751/associate-a-color-palette-with-ggplot2-theme
##
my_colours <- c("#fd7f6f", "#7eb0d5", "#b2e061", "#bd7ebe", "#ffb55a", "#ffee65", "#beb9db", "#fdcce5", "#8bd3c7")
my_pastels <- c("#66C5CC", "#F6CF71", "#F89C74", "#DCB0F2", "#87C55F", "#9EB9F3", "#FE88B1", "#C9DB74", "#8BE0A4", "#B497E7", "#D3B484", "#B3B3B3")
my_greys <- c("#000000", "#333333", "#666666", "#999999", "#cccccc")
my_vivids <- c("#E58606", "#5D69B1", "#52BCA3", "#99C945", "#CC61B0", "#24796C", "#DAA51B", "#2F8AC4", "#764E9F", "#ED645A", "#CC3A8E", "#A5AA99")

my_bolds <- c("#7F3C8D", "#11A579", "#3969AC", "#F2B701", "#E73F74", "#80BA5A", "#E68310", "#008695", "#CF1C90", "#f97b72", "#4b4b8f", "#A5AA99")

library(systemfonts)
library(showtext)
## Clean the slate
systemfonts::clear_local_fonts()
systemfonts::clear_registry()
##
showtext_opts(dpi = 96) # set DPI for showtext
sysfonts::font_add(
  family = "Alegreya",
  regular = "../../../../../../fonts/Alegreya-Regular.ttf",
  bold = "../../../../../../fonts/Alegreya-Bold.ttf",
  italic = "../../../../../../fonts/Alegreya-Italic.ttf",
  bolditalic = "../../../../../../fonts/Alegreya-BoldItalic.ttf"
)

sysfonts::font_add(
  family = "Roboto Condensed",
  regular = "../../../../../../fonts/RobotoCondensed-Regular.ttf",
  bold = "../../../../../../fonts/RobotoCondensed-Bold.ttf",
  italic = "../../../../../../fonts/RobotoCondensed-Italic.ttf",
  bolditalic = "../../../../../../fonts/RobotoCondensed-BoldItalic.ttf"
)
showtext_auto(enable = TRUE) # enable showtext
##
theme_custom <- function() {
  font <- "Alegreya" # assign font family up front

  theme_classic(base_size = 14, base_family = font) %+replace% # replace elements we want to change

    theme(
      text = element_text(family = font), # set base font family

      # text elements
      plot.title = element_text( # title
        family = font, # set font family
        size = 24, # set font size
        face = "bold", # bold typeface
        hjust = 0, # left align
        margin = margin(t = 5, r = 0, b = 5, l = 0)
      ), # margin
      plot.title.position = "plot",
      plot.subtitle = element_text( # subtitle
        family = font, # font family
        size = 14, # font size
        hjust = 0, # left align
        margin = margin(t = 5, r = 0, b = 10, l = 0)
      ), # margin

      plot.caption = element_text( # caption
        family = font, # font family
        size = 9, # font size
        hjust = 1
      ), # right align

      plot.caption.position = "plot", # right align

      plot.background = element_rect(fill = "navajowhite"),
      axis.title = element_text( # axis titles
        family = "Roboto Condensed", # font family
        size = 12
      ), # font size

      axis.text = element_text( # axis text
        family = "Roboto Condensed", # font family
        size = 9
      ), # font size

      axis.text.x = element_text( # margin for axis text
        margin = margin(5, b = 10)
      )

      # since the legend often requires manual tweaking
      # based on plot content, don't define it here
    )
}

## Use available fonts in ggplot text geoms too!
update_geom_defaults(geom = "text", new = list(
  family = "Roboto Condensed",
  face = "plain",
  size = 3.5,
  color = "#2b2b2b"
))

## Set the theme
theme_set(new = theme_custom())
```

Introduction

This is a dataset pertaining to furniture prices at IKEA, modified for ease of analysis and plotting.

Data

ABCDEFGHIJ0123456789

item_id <dbl>	name <chr>	category <fct>	price <dbl>	old_price <chr>	sellable_online <lgl>
29123958	MINNEN	Beds (208)	395.0	SR 445	TRUE
49278341	BRIMNES	Beds (208)	895.0	SR 925	TRUE
50461230	SMÅGÖRA	Beds (208)	595.0	No old price	TRUE
89326463	PLATSA	Beds (208)	2111.0	SR 2,205	TRUE
50468953	VATTVIKEN	Beds (208)	995.0	No old price	TRUE
69326609	SLÄKT	Beds (208)	540.0	No old price	FALSE
59099136	BRIMNES	Beds (208)	795.0	No old price	TRUE
40395245	NEIDEN	Beds (208)	99.0	No old price	TRUE
69277307	LEIRVIK	Beds (208)	1195.0	No old price	TRUE
70395239	NEIDEN	Beds (208)	199.0	No old price	TRUE

Next

123456

...

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1-10 of 3,211 rows | 1-6 of 15 columns

Download the Modified data

Data Dictionary

Quantitative Variables

Write in.

Qualitative Variables

Write in.

Observations

Write in.

Plot the Data

Task and Discussion

Complete the Data Dictionary. Create the graph shown and discuss the following questions:

• What is the kind of plot used in the chart?
• What variables have been used in the chart?
• What can you say about the scale on X-axis?
• What can you say about prices of items that are available in single colour versus those that are available in more than one colour?
• What is a good hypothesis to interpret the double-humped nature of some of the curves?