Module 6: Data Visualization Principles
- Choose the right chart type for the data and message
- Avoid common visual distortions like truncated axes
- Design dashboards that highlight the key insight, not just the data
A chart's job is to make a pattern visible faster than a table of numbers can. This module covers choosing the right form: line charts for trends over time, bar charts for comparing categories, and scatter plots for relationships between two variables, while avoiding pie charts for more than four or five slices, where they become hard to read accurately. You will learn how a truncated y-axis (one that doesn't start at zero) can make a small difference look dramatic and why this is considered misleading practice in professional reporting. Finally, you will practice applying a visual hierarchy: using color, size, and labels to draw the eye to the one number or trend that matters most, rather than presenting every data point with equal visual weight.
1. A bar chart with a y-axis that starts at 90 instead of 0 risks:
2. To show how monthly revenue changed over two years, the most appropriate chart is generally a:
3. Good dashboard design generally aims to: