TT, ~ 1
Statures, correlation of, for father ' matical expectation of moments,
and son, 160; diagrams, facing 395; distribution of means, 395 ;
166, 174 ; constants, (qu. 3) 189; Korrelations theorie, 397.
testing for normality, 322-328; Type of array, def., 164.
for isotropy, 329-331; diagram
of diagonal distribution, 325, of UrtiMATE classes and frequencies,
fitted contour-lines, 327. def., 12; sufficiency of, for tabu-Stead,
 H. (5., correlation-coefficients, lation, 12-13.
ref., 392. Universe, def., 17; specification of,
Stevenson, T. H. C., refs., birth- 37, 18.
rates, correction of, for age-dis- U-shaped frequency - distributions,
tribution, 226. 102-105.
Stigmatic rays on poppies, frequency,
 78; unsuitability of VALUE, annual, of dwelling-houses,
median for such distributions, 116. table, 83; median, (qu. 4) 131;
Stirling, James, expression for fac- quartiles, (qu. 3) 155.
torials of large numbers, 304. — of estates in 1715, table, 100 ;
Stratton, F. J. M., refs., errors of diagram, 101.
agricultural experiment, 396. Variables, theory of, generally, 75-“Student
 (pseudonym), refs., law 253; def, 7, 75.
of small chances, 273, 393 ; prob- Variance, for square of standard deable
 errors, 355, 395; deviations viation, 144.
from Poisson's Law, 393; prob-  Variates, def., 150.
able errors of Spearman’s corre- Variation, coefficient of, 149 ; stan
lation-coefficients, 395; method dard error of, 351, 352.
of cereal testing, 396. Variety, tests, errors in, refs., 396.
Surface, F. M., refs., errors in variety ~~ Venn, John, refs., Logic of Chance,
tests, 396. sex-ratio, 273, 361.
Symmetrical frequency - distribu- ~~ Verschaeffelt, E., relative dispersion,
tions, 87-90. See also Frequency- 149. Refs., measure of relative
distributions ; Normal curve. dispersion, 154.
Symons, G. J., use of word “sta- Vigor, H. D., data cited from, 163.
tistics *’ in British Rainfall, 3. Refs., sex-ratio, 273.
TABULATION, of statistics of attri- WAGES of agricultural labourers. See
butes, 11-14, 37 ; of a frequency- Earnings.
distribution, 81-83 ; of a correla- Wages, real, refs., 390-391.
tion table, 164. Warner, F., refs., study of defects in
Tatham, John, refs., standardisation school children, notation for staof
 death-rates, 226. “tistics of attributes, 15.
Thomson, G. H., refs., The Essentials ~~ Water analysis, methods, refs., 393.
of Mental Measurement, 396. Waters, A. C., refs, estimating
Thorndike, E. L., refs., methods of intercensal populations, 130.
measuring correlation, 333; Weather and crops, correlation, 196
Theory of Mental and Social 197 ; refs., 208.
Measurements, 361. Weight of males in U.K., table, 95 ;
Time-correlation problem, 197-201 ; diagram, 94; mean, median, and
refs., 208-209, 392. mode, (qu. 2) 131; standard
Tocher, J. F., refs., contingency, 390. deviation, mean deviation,. and
Todhunter, I., refs., History of the quartiles, (qu.) 155.
Mathematical Theory of Prob- Weighted mean. See Mean,
ability, 6. weighted ; also Mean, geometric ;
Trachtenberg, M. I., refs., property Median; Mode.
of median, 154. Weldon, W. F. R., dice-throwing
Tschuprow, A. A., refs., mathe- experiments, 258-259, 373-376.

INDEX A