normality
(nɔːˈmælɪtɪ)
[f. normal a. + -ity: cf. F. normalité, It. -ita, Sp. -idad.]
1. a. The character or state of being normal.
| a 1849 Poe Eureka Wks. 1865 II. 153 In a condition of positive normality or rightfulness. 1866 Athenæum 29 Dec. 873 Normality..gives us only the negative notion of the absence of defect. 1896 Allbutt's Syst. Med. I. 150 Those parts in which it is their business to maintain constancy, that is normality. |
b. spec. in Statistics (cf. normal a. and n. A. 2 e).
| 1928 Amer. Jrnl. Psychol. XL. 348 We can change 0·93 into a P.E. [sc. probable error] by multiplying by 0·845 (assuming normality of distribution). 1938 A. E. Waugh Elem. Statistical Method vi. 95 In most statistical problems there is no a priori reason for expecting normality of distribution—no reason for believing in advance that the data will be distributed as are the coefficients of the expansion (½ + ½)n. 1968 Brit. Med. Bull. XXIV. 211/1 The assumption of Normality is central to the most powerful statistical techniques. 1974 Nature 22 Mar. 288/1 A weighted least squares analysis of the two sets of correlations..provides (given normality) a test of goodness of fit of the model. |
2. Chem. The concentration of a solution as a proportion of the normal concentration.
| 1903 Sci. Abstr. VI. 315 Boric acid was agitated..with an excess of aqueous hydrochloric acids of different normalities. 1928 A. W. Wellings Volumetric Analysis ii. 41 The normality of the acid solution will be 0·1N. × 18·6/50. 1966 McGraw-Hill Encycl. Sci. & Technol. III. 361/2 In double-decomposition reactions normality may be an ambiguous concept unless referred to a specific reaction. 1972 Nature 8 Sept. 69/3 At higher concentrations of the salt..the viscosity was considerably smaller (1·60 at a normality of 0·50). |