Overview
This lecture covers how data visualisation is used to make data easy to understand, but also how it can be manipulated to misrepresent facts.
Data Visualisation Basics
- Data visualisation translates complex data into visual formats like charts and graphs to reveal patterns and trends.
- Visual aids make large sets of numbers easier to interpret and understand.
Methods of Data Misrepresentation
- Cherry picking data is selecting only data that supports a desired outcome, giving a false impression.
- In the veterinary industry, positive results are often selectively reported, especially in industry-funded studies.
- Human drug trial results funded by industry are more likely to show positive outcomes than those funded by the government.
Manipulative Visualisation Techniques
- Using cumulative data instead of annual data can falsely show consistent growth by always increasing the graph.
- Pie charts can mislead if survey participants can vote for more than one option, resulting in totals exceeding 100%.
- Bar graphs can exaggerate trends by adjusting the y-axis scale to make small differences appear significant.
Consequences and Awareness
- Data manipulation is common in politics, media, and industry to influence public perception in their favor.
- Being aware of these techniques allows individuals to critically evaluate presented information and make informed decisions.
Key Terms & Definitions
- Data Visualisation — converting raw data into visual formats like charts or graphs for easier understanding.
- Cherry picking — selecting only supportive data points, ignoring evidence that does not fit the desired narrative.
- Cumulative Data — data that adds up over time, always making the graph look like it is rising.
- Annual Data — data shown separately for each year, revealing year-to-year changes.
- Y-axis Manipulation — altering the scale of the graph to exaggerate differences.
Action Items / Next Steps
- Review examples of misleading charts in news media.
- Practice identifying potential misrepresentations in charts and graphs encountered in everyday life.