SUPPLEMENTS—ADDITIONAL REFERENCES. 391 
(18) MARSHALL, A., Money, Credit, and Commerce, Macmillan, London, 1923. 
For the student of the cost of living in Great Britain the following 
are useful : — 
(19) *“ Labour Gazette Index Number: Scope and Method of Compilation,” 
Lab. Gaz., March 1920 and Feb. 1921. 
(20) ** Final Report on the Cost of Living of the Parliamentary Committee 
of the Trades Union Congress” (The Committee, 32 Eccleston Sq., 
London, 1921) ; critical notices of the same in the Labour Gazette, Aug. 
and Sept. 1921 ; and review by A. L. Bowley, Econ. Jour., Sept. 1921. 
(21) BowLEy, A. L., Prices and Wages in the United Kingdom, 1914-20, 
Oxford, 1920 (Clarendon Press). 
(22) MarcH, L., ‘Rapport sur les indices de la situation économique,” 
Bulletin de I’ Institut International de Statistique, t. xxi., pt. 2, p. 3. 
(23) Gxt, C., ‘“‘Quelques considérations au sujet de la construction des 
nombres indices des prix, ete.,” Metron, vol. iv., 1924, p. 3. 
(24) EpceworrH, F. Y., “The Plurality of Index Numbers,” Economic 
Journal, vol. xxxv., 1925, p. 379. 
(25) EpcEworTH, F. Y., “The Element of Probability in Index Numbers,” 
Jour. Roy. Stat. Soc., vol. Ixxxviii., 1925, p. 557. 
(26) BowLEY, A. L., ‘‘The Influence on the Precision of Index Numbers of 
the Correlation between the Prices of Commodities,” Jour. Roy. Stat. 
Soe., vol, 1xxxix., 1926, p. 300. 
Correlation : History (p. 188). 
(27) Pearson, K., “Notes on the History of Correlation,” Biometrika, vol. 
xiii., 1920, p. 25. 
Fit of Regression Lines (p. 209). 
(28) PEARsox, Karr, “On the Application of Goodness of Fit Tables to test 
Regression Curves and Theoretical Curves used to describe Observa- 
tional or Experimental Data,” Biometrika, vol. xi., 1916-17, p. 237. 
(Criticises and extends the work of Slutsky.) 
(29) FisuER, R. A., ‘“The Goodness of Fit of Regression Formule, and the 
Distribution of Regression Coefficients,” Jour. Roy. Stat. Soc., vol. 
Ixxxv., 1922, vp. 597. 
Correlation in Case of Non-linear Regression (p. 209). 
(80) WicksELL, S. D., “On Logarithmic Correlation, with an Application to 
the Distribution of Ages at First Marriage,” Meddelande fran Lunds 
Astronomiska Observatorium, No. 84, 1917. Svenska Aktuarie- 
forenings Tidskrift. 
(81) WickseLL, S. D., “The Correlation Function of Type A,” Kungl. 
Svenska Vetenskapsakademiens Handl., Bd. lviii., 1917. 
(32) Pearson, K., “Ou a General Method of Determining the- Successive 
Terms in a Skew Regression Line,” Biometrika, vol. xiii., 1921, p. 296. 
(38) Pearsox, KArr, “On the Correction necessary for the Correlation 
Ratio »,” Biometrika, vol. xiv., 1923, p. 412. 
Correlation : Effect of Errors of Observation, etc. (p. 225). 
(34) Harr, BERNARD, and C. SPEARMAN, ‘General Ability, its Existence 
and Nature,” Brit. Jour. Psychology, vol. v.,.1912, p. 51. 
There has been a good deal of controversy about these formule and 
their applications in psychological work : ¢f. (119) Brown and Thomson, 
and the references there given, critical notice of the same in Brit. Jour. 
Psych. , vol. xii., 1921, p. 100, and—