| 释义 |
normality|nɔːˈmælɪtɪ|
[f. normal a. + -ity: cf. F. normalité, It. -ita, Sp. -idad.]
1. a. The character or state of being normal.
a1849Poe Eureka Wks. 1865 II. 153 In a condition of positive normality or rightfulness. 1866Athenæum 29 Dec. 873 Normality..gives us only the negative notion of the absence of defect. 1896Allbutt'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).
1928Amer. 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). 1938A. 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. 1968Brit. Med. Bull. XXIV. 211/1 The assumption of Normality is central to the most powerful statistical techniques. 1974Nature 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.
1903Sci. Abstr. VI. 315 Boric acid was agitated..with an excess of aqueous hydrochloric acids of different normalities. 1928A. W. Wellings Volumetric Analysis ii. 41 The normality of the acid solution will be 0·1N. × 18·6/50. 1966McGraw-Hill Encycl. Sci. & Technol. III. 361/2 In double-decomposition reactions normality may be an ambiguous concept unless referred to a specific reaction. 1972Nature 8 Sept. 69/3 At higher concentrations of the salt..the viscosity was considerably smaller (1·60 at a normality of 0·50). |