3 steps to design your visualization charts

Data visualization is quite important for analysts, researchers, or scientists. A few days ago, we saw many visualized charts on news, website, or slides, to emphasize the outbreak and affection of COVID 19. Today, I would like to follow this trend, using John Burn-Murdoch’s chart as a good example and providing you with 3-step tips to make better of your charts.

Source: https://twitter.com/jburnmurdoch

Step 1, Review materials

The material here means your data. There are tons of columns in your data sets and for a chart, you must need to understand what is your topic. In this step, you must decide which information you want to disclose in your charts. In our example, the number in the chart is the confirmed case with the testing process. Some countries had lower cases just because they haven’t started testing yet. Use the proper key figures is quite important.

Time Frame

The key point here for a chart is to compare with others and differentiated the present. So we need to put our data on the same page. In the example case, the time frame started from the point of the 100th case confirmed, which eliminate the date difference of the first case and the transmission gap.

Step 2, Decide that from what perspectives you want to show data to the audience

After the first step, you may have a clear map of the topic you want to present to the audience. In this step, you need to think about what kind of charts you would like to use to present. You have many choices such as bar, bubble, histogram, treemap, and more. I would have another article to discuss how to select the type of chart. Then we move to the next few points.

X-axis, Y-axis

• Think about what conclusion that you want your audiences to have
• Scale: log or linear or other scales (log scale bring small cases to the table )

The linear scale is the original scale to display data. But it would be affected by the total number of data. For example, when we compare the outbreaks in two countries, the country with more population might show higher growth or a larger number on the chart, which may mislead the conclusion. Consider using a log scale to eliminate the base-problem and bring small base objects to the table.

The below charts (source:https://www.wikiwand.com/en/Logarithmic_scale) show the log scale (blue ) can remove some bias compares to the linear scale(green).

Linear, exponential, and log scale

Unit

Use the same unite is important. And when you have large numbers, you can consider using $K, $M, or apostrophe to make a simple display on your charts.

Step 3, Optimize your chart

In this step, I will put some bullet points about what you need to improve after the basic chart has been made.

Color

• Emphasize the important information through using colors. In our example above, the US, UK, and Italy have been colored because the author wants to emphasize them and he kept other countries in the color gray.
• Align through charts in a report. For example, you may have two charts regarding the revenue portion of countries. In this case, for the same country, you need to use the same color in two charts.

Legend VS label

You should consider carefully while using legend or label to help the audience understand your charts. Here comes a chart that I don’t think legend is a good choice for it.

Too many subjects need to be mapped

In this chart, you can see obviously different in the display. You can feel that the right-hand side design is better to read.

Source: https://depictdatastudio.com/directly-labeling-line-graphs/

Auxiliary line

Use auxiliary lines to help the audience get into the scenario of your chart. For the chart below, it used the auxiliary lines to point out some meaningful prices in history, which help the audience to understand this stock more.

The Auxiliary lines help to point out the highest and lowest price within a period

The titles

Put the conclusion or the finding on the tiles, enabling your audiences to understand the message you want to deliver to them. The title of our example is pretty obvious and specific to deliver the message of the chart.

Most western countries are on the same coronavirus trajectory. Hong Kong and Singapore have limited the spread; Japan and South Korea have slowed it.

Okay, that is the 3-step tips I’d like to share. There are some details of each small topic that I can go deep dive into it. I will have more articles about those details, stay tuned.