Written for readers who have never studied statistics, so that reading one page at a time traces the line of reasoning. Every page uses the same primate dataset and nothing else.
The data are the primate portion of PanTHERIA (Jones et al. 2009, Ecology 90: 2648), also used in the courses Statistics I and II. Some species lack records for some variables, so the number of species differs from page to page.
- LOOKING AT DATA
- 01SUMMARIZING DATA
Does the mean describe a typical species?
Mean, median, and spread. Which number should summarize skewed data.
- 02GRAPHS
Change one axis, and the data look different
Histograms, scatter plots, and log scales for data spanning orders of magnitude.
- 03CORRELATION AND CAUSATION
Do longer-lived species range more widely?
The correlation coefficient, and the third variable behind a relationship.
- INFERRING THE WHOLE FROM A PART
- 04SAMPLING
Why one spoonful tells you how the soup tastes
Samples and the central limit theorem. More data does not fix a biased sample.
- 05CONFIDENCE INTERVALS
What exactly is 95% about a 95% interval?
Estimating the whole from a part, with a range rather than a single number.
- 06HYPOTHESIS TESTS
When a real difference is “not significant”
Measuring whether chance could produce a result. p-values and effect size.
- PROBABILITY AND EQUATIONS
- 07PROBABILITY AND BAYES
Do large species form large groups, or the other way round?
The direction of conditional probability, and Bayes’ theorem.
- 08REGRESSION
If body mass is ten times larger, how much larger is the home range?
Regression lines, reading the slope, and residuals.
Links to the courses
Each page ends with links to the course sessions that cover the same idea. The course map shows which session of which course covers what. The course sites are in Japanese.