Best way to display data question HELP!

[rui97]

Question:
The relationship between the variables size (small, med, large, XL, XXL) and number ordered is best displayed by
A. parallel boxplot
B. back to back stemplot
C. Histogram
D. Bar chart
E. Scatterplot

I think it's A since the data is a numerical and categorical variable, however the answers says its D. I thought bar charts were for 2 categorical variables?

[Zealous]

Bar chart would work better, think of it like this.

For example, the data we might receive could be like this:
Small: 14
Medium: 20
Large: 15
XL: 18
XXL: 7

So there were 14 orders of the small drink size, 20 of the medium size etc. The data here is categorical and numerical.
A boxplot would be better used when we have more numerical data. Boxplots work best when there are a lot of pieces of numerical data, as boxplots display Q1, Q3, etc.
In this case though, we have a category, then the frequency, which can be best viewed on a bar chart.

[rui97]

Ah yes I understand you. When I thought of the question, I thought maybe there were multiple orders from say, different outlets. Hopefully the exam wont have anything too ambiguous. Thanks for your help!

[BLACKCATT]

number ordered is more like a frequency rather than variable, so why is it stated as a variable..?
Plus bar charts are univariate which only involve a single variable

[Zealous]

number ordered is more like a frequency rather than variable, so why is it stated as a variable..?
Plus bar charts are univariate which only involve a single variable

That's a good way of putting it. The question isn't worded the best I guess then. I understand what you're saying.