2-15_ggplot2_practicals_questions.qmd

## ggplot: Questions {.unnumbered}

Load the ggplot2 library (install it if you have to) and the diamonds data set using data()

```{r, eval=F}
# if needed install.packages("ggplot2")
library(ggplot2)
data("diamonds")
```

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### Question 1

Explore the data set using dim(), str() and help(), which variables are continuous, which variables are discrete? Is this data set ready for plotting with ggplot?
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### Question 2

Use ggplot to plot a scatterplot of the relationship between the diamonds' carat a
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### Question 3

Make all dots darkblue and set the alpha value to 0.1
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### Question 4

Visualize the influence of the color of a diamond on its price by mapping the diamond color to the color aesthetic
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### Question 5

Use a ggplot barplot to visualize diamond clarity depending on color, map diamond color to x and diamond clarity to fill
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### Question 6

Create a boxplot of the carat of a diamond based on its clarity and add whiskers using stat_boxplot
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### Question 7

Add a geom_point layer to the previous plot mapping the diamonds price to the color
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### Question 8

Create a histogram of the price of the diamonds and separate the histograms into facets using diamond color, choose a good binwith or number of bins
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### Question 9

Create a grid of facets of the same histogram by comparing both color and cut
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### Question 10

Use `aggregate(diamonds, by = list(cut = diamonds$cut, color = diamonds$color), mean)` to calculate the mean of all variables by cut and color. Create a heatmap of the mean prices by cut and color using geom_tile
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### Question 11

Change the title of the heatmap to "Average prices"
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### Question 12

Change the gradient of the fill scale using 'scale_fill_gradient2'. Have it go from darkblue to white to darkred, set the midpoint to 4500
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### Question 13

Choose and add a theme to the heatmap, or create a theme yourself using the options listed at <http://ggplot2.tidyverse.org/reference/theme.html>
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