Reading and understanding charts correctly

In short: Charts present data clearly but can also deceive. Those who check axes, scales and source read them correctly.

In more detail: Each chart type suits a particular question.

In detail

• Bar chart: Compares categories.
• Line chart: Shows developments over time.
• Pie chart: Shares of a whole; from about six slices confusing.
• Histogram: Distribution of measured values (normalverteilung).
• Scatter plot: Relationship between two quantities (korrelation-und-kausalitaet).
• Deceptions: Truncated y-axis, unequal scales, 3D effects, choice of time period.
• Checking questions: Who collected the data, how many data points, which period?
• Absolute and relative: Percentages need a reference value (stichproben-und-umfragen-richtig-bewerten).