Data Visualization
IntermediateData visualization is the presentation of data in graphical form, such as charts, graphs and maps, to make information easier to understand, analyse and communicate.
Large amounts of numbers can be difficult to interpret. Visualizations help people see patterns, trends, comparisons and outliers that might be hidden in tables of figures.
Different types of visualization suit different purposes. Line charts show changes over time, such as a share price or GDP growth. Bar charts compare quantities across categories, such as sales by region. Pie charts show parts of a whole, although they can be hard to read with many slices. Scatter plots show relationships between two variables. Heat maps use colour to show values across a grid.
For example, a line chart showing a company's revenue and profit over ten years can quickly reveal whether profit margins have improved or declined, which would take much longer to see from a table.
Good data visualization is clear, accurate and honest. Poor or misleading visualizations can distort understanding, for example by starting a chart's vertical axis well above zero to exaggerate small changes, using inconsistent scales, or cluttering charts with unnecessary detail. In finance, visualizations are widely used in reports, presentations, dashboards and investment research.
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