Regression & ANOVA Practice
Interpret correlation, fit and use least-squares regression lines, and read one-way ANOVA output.
1 Practice
Type your answer and press Check answer (or Enter). A wrong answer earns a hint; a second miss earns a stronger hint; a third miss walks you through the full solution. Scores and streaks are session-only.
2 What you’ll practice
Every problem is generated fresh from templates across several question types — a problem never repeats until its whole pool is used up.
Interpret r
Sign = direction, |r| = strength.
Slope
b = r·(sy/sx).
Intercept
a = ȳ − bx̄.
Fit data
Least squares on 5 points.
Predict
Plug x into ŷ = a + bx.
r-squared
% of variation explained.
ANOVA F
F = MSB/MSW.
3 Watch out for these
The mistakes students make most often on these problems.
r measures association. Causal claims need experiments or strong theory — check for lurking variables.
Predictions are only trustworthy near the observed x-range.
a is the prediction at x = 0, which is often outside the data and sometimes nonsensical.