Elementary Statistical Methods

abscissa algebraic Appendix approximately arbitrary origin arithmetic arithmetic mean average called Chapter chart class interval Class Sort correlation coefficient corresponding cumulative frequency cumulative percentage data of Table entries equal equation estimate Figure formula frequency curve frequency distribution frequency polygon Galton given height histogram horizontal illustrated increase indicate individual intelligence quotient interval units Karl Pearson kurtosis language score large number mathematical mean and standard measure median midpoint mode multiplied negative normal curve normal distribution number of heads obtained ordinate percentile rank person population position quartile random samples range Reading Speed regression lines relationship represent result sampling distribution scale of scores score units skewness square standard deviation standard scores statistical method step interval student subtracted Suppose symbol T-scores Teachers tion trait variable variance variation vertical width of interval X₁ zero ΣΥ ΣΧ