After read chapter 1 of book《Head First Statistics》, I found there are some good points about how to use different charts in reports. So I summarized below to share with everyone.
1. Pie charts are used to compare the proportions of different groups or categories. It’s usually easy to tell at a glance which groups have a high frequency compared with the others. Pie charts are less useful if all the slices have similar sizes, as it’s difficult to pick up on subtle differences between the slice sizes.
2. Bar charts are ideal in situations where categories are roughly the same size, as you can tell with far greater precision which category has the highest frequency. It makes it easier for you to see small differences.
Vertical bar charts tend to be more common, but horizontal bar charts are useful if the names of your categories are long. They give you lots of space for showing the name of each category without having to turn the bar labels sideways.
With a bar chart, it’s also easy to show multiple sets of data on the same chart.
The split-category bar chart: You can compare frequencies by showing related bars side by side. This sort of chart is useful if you want to compare frequencies, but it’s difficult to see proportions and percentages.
The segmented bar chart: You also can show proportions and total frequencies by stacking the bars on top of each other.
3. Histograms are like bar charts but with two key differences. The first is that the area of each bar is proportional to the frequency, and the second is that there are no gaps between the bars on the chart. Here’s an example of a histogram showing the average number of games bought per month by households in Statesville:
4. Line charts are good at showing trends in your data. They are often used to show time measurements. What you shouldn’t do is use a line chart to draw lines from category to category. It should only be used to show categorical data if you’re showing trends for each category, and use a separate line for each category.
