Statistics & Data· Study notes
Discrete and Data
Data displays, center and spread, the normal distribution, correlation and regression, sampling and experiments, random variables, and the logic of confidence intervals and hypothesis tests.
What you'll be able to do
- Choose and read the right display and summary for a data set
- Use z-scores and the normal model
- Fit and interpret a least-squares line
- Build a confidence interval and run a hypothesis test
Read the notes as a guided lesson
Walk the notes one box at a time — prose, worked examples, quick checks — with a timed practice round after every section. For the full course with interactive lessons, go back to the course.
Every test ends with a score by topic and a list of what to revisit. Test out of a topic with 80% or better to mark it mastered.
Topics
Center and Spread
4 lessonsMean, median, variance and standard deviation
Percentiles and Box Plots
4 lessonsThe five-number summary and outliers
The Normal Distribution
4 lessonsZ-scores, the empirical rule and the standard normal table
Two Variables
4 lessonsScatter plots, correlation and the least-squares line
Sampling and Experiments
4 lessonsWhere data comes from and what can go wrong
Random Variables
4 lessonsExpected value, variance and combining variables
Binomial and Geometric
4 lessonsCounting successes and waiting for the first one
Sampling Distributions
4 lessonsHow a statistic varies from sample to sample
Confidence Intervals
4 lessonsEstimating with a margin of error
Hypothesis Tests
4 lessonsIs the effect real, or could chance explain it?