Statistics, data and evidence · Perspectives

Can the same data support opposite conclusions depending on how it is shown?

Axes can start at zero or not, scales can be linear or logarithmic, and time periods can be chosen carefully. Each choice can be defended, and each changes what a reader sees. This question asks whether visualising data is a neutral act.

Claims

Different scales reveal different true features of the data, so using several views gives fuller knowledge, not distortion.
Good conventions, such as labelled axes and stated sources, let readers interpret a graph correctly.

Counterclaims

Most readers look at the shape of a graph, not its axes, so the designer's choices shape belief in ways readers do not notice.
Graphs are often made to persuade, so they always carry the perspective of whoever made them.

Real-life situations from mathematics

COVID-19 graphs on log scales

In 2020 many news outlets showed case numbers on logarithmic scales, which make steady exponential growth look like a straight line. Some readers took a straightening line to mean the epidemic was slowing when it was not.

Truncated axes

A bar chart whose vertical axis starts at 95% instead of 0% can make a difference of two percentage points look enormous. The numbers are correct; the impression is not.

Check dates and figures in a reliable source before you use them, and cite that source.

Use this in your TOK work

Essay. Fits titles about representation, bias or the role of images in knowledge.

Exhibition. Two versions of the same graph, one on a linear and one on a log scale, make an excellent object pair.

Link it to the prescribed title or the exhibition prompt you are working on, in your own words. See using maths examples in your essay and choosing exhibition objects.

Themes and study heading

Knowledge and language Knowledge and politics Perspectives

Different views of what mathematics is and whose it is.