reliability
(rɪlaɪəˈbɪlɪtɪ)
[f. next + -ity.]
1. The quality of being reliable, reliableness.
| 1816 Coleridge Lett. (1895) II. 667 Either in the taste, courtesy, or reliability of his judges. 1817 ― Biog. Lit. iii. (Bohn) 33 Perfect consistency, and (if such a word might be framed) absolute reliability. 1847 in Webster. 1856 Geo. Eliot Ess. (1884) 126 An air of seriousness and reliability. 1860 Adm. Fitzroy in Merc. Marine Mag. VII. 355 The reliability and the universality of the laws of storms. 1887 Spectator 18 June 827/2 We want doctors to bear a stamp of reliability, like the coinage. |
2. Statistics. The extent to which a measurement made repeatedly in identical circumstances will yield concordant results.
| 1904 Amer. Jrnl. Psychol. XV. 238 The reliability with which any system of measurement represents any particular form of intelligence. 1925 F. C. Mills Statistical Meth. xvi. 561 By the study of successive samples, and by the testing of the subordinate elements in a given sample when broken up into significant sub-groups, much more may be learned as to the reliability of a given measure..than by unquestioning acceptance and uncritical employment of the usual mathematical formulas for probable errors. 1938 A. E. Waugh Elem. Statistical Meth. vii. 138 We can increase the reliability of the mean by studying more cases, and..the reliability is greater also when the variation among the original figures is small. 1950 J. P. Guilford Fundamental Statistics in Psychol. & Educ. (ed. 2) xvii. 473 Tests of differences and correlation coefficients may often prove to be insignificant merely because the measures used were lacking in reliability. 1978 R. J. Jesson Statistical Survey Techniques i. 15 In considering reliability we shall be referring to a measure of the closeness of each observation to its own average over repeated trials. |
3. attrib., as
reliability engineer,
reliability race,
reliability test,
reliability trial;
reliability coefficient, any of various measures of statistical reliability;
freq. the coefficient of correlation between two sets of measurements made of the same set of quantities.
| 1910 C. Spearman in Brit. Jrnl. Psychol. III. 281 A very convenient conception is that of the ‘reliability coefficient’ of any system of measurements for any character. By this is meant the coefficient between one half and the other half of several measurements of the same thing. 1930 Psychol. Rev. XXXVII. 140 The reliability coefficient of a variable, X, is a special type of correlation coefficient which indicates the degree to which individuals systematically differ from each other in the trait as measured. 1954 Psychol. Bulletin LI. 229/1 The several types of reliability coefficient do not answer the same questions and should be carefully distinguished. 1972 Jrnl. Social Psychol. LXXXVII. 48 The split-half method was employed and resulted in a reliability coefficient for the instrument of ·83. |
| 1969 Word Study Apr. 3/2 The reliability engineers, on the other hand, did not want to avoid taboo words; they were chiefly interested in alarming the program to potential failures. 1977 Chicago Tribune 2 Oct. xii. 57/4 (Advt.), Reliability Engineer, to direct and perform component reliability studies, coordinate with system requirements, and function as reliability consultant. |
| 1907 Strand Mag. Nov. 491/2 A result extraordinarily interesting should be worked out from this thousand-mile [car] reliability race. |
| 1904 Technics Aug. 114 As a ‘reliability test’, the car was driven from London to Newport (Mon.), a distance of about 160 miles. 1929 Even. News 18 Nov. 16/4 [He] crashed on his motor-cycle while taking part in a reliability test on Portsdown-hill. |
| 1902 Car 3 Sept. 43/1 The cars entered for the Automobile Club's Reliability Trials which are being held this week began to arrive at the Crystal Palace at a very early hour. 1904 To-Day 18 May 58/2 The Automobile Club has arranged to hold a reliability trial for motor boats. 1963 P. Drackett Motor Rallying i. 9 But the true progenitor of the rally was the reliability trial. 1970 Which? July 199/1 We have not done any extended reliability trials on the single samples of television sets we tested. |