Appendix 1 — Symbols and Notation (Cheat Sheet)
A quick reference to the symbols used in this book.
| Symbol | Meaning | Example |
|---|---|---|
| $$\Sigma$$ | Summation (add them up) | $$\Sigma X = 2+4+6=12$$ |
| $$\bar{X}$$ | Sample mean | $$\bar{X} = \tfrac{12}{3} = 4$$ |
| $$\mu$$ | Population mean | “The true average of all scores” |
| $$s$$ | Sample standard deviation | Spread of quiz scores |
| $$\sigma$$ | Population standard deviation | Spread of SAT scores |
| $$df$$ | Degrees of freedom | $$df = n-1 = 29$$ if $$n=30$$ |
| $$t$$ | t-test statistic | Compare two group means |
| $$F$$ | ANOVA statistic | Compare 3+ group means |
| $$r$$ | Pearson correlation | Strength of linear relationship |
| $$R^2$$ | Coefficient of determination | Proportion of variance explained |
| $$\chi^2$$ | Chi-square statistic | Compare observed vs. expected counts |
| $$p$$ | Probability value | “p < 0.05” → significant result |
Practice self-test quiz
In the space below, please find practice problems and self-test quizzes. For full access, please signup free.