Published online by Cambridge University Press: 18 August 2016
The publication of the Sickness and Mortality Experience of Registered Friendly Societies, the work of our late distinguished member, Mr. W. Sutton, has directed the serious attention of the Manchester Unity of Oddfellows to the question of the continued reliability of the Tables on which the Society has been accustomed to base its financial estimates, and as the result of the interest thus awakened, the Actuaries of the Order have been instructed to make a complete investigation of its experience during the five years 1893–97. From the immensity of the data to be handled in this investigation (these being contributed by about 3,500 branches and comprising, inter alia, some three million years of life and 40,000 deaths) it has been necessary, at the outset, to closely consider the methods of tabulation and classification to be adopted, and preliminary experiments on a somewhat elaborate scale have accordingly been required. The results of these experiments appear to possess a definite value in relation to the subject of friendly society experience, and I am emboldened on this account to offer the following notes respecting them for the consideration of this meeting.
page 276 note * In these comparisons I have somewhat freely used the term “expected deaths” as implying the product of the numbers exposed to risk multiplied by the tabular qx. This term is, however, scarcely accurate, the true “expected deaths” at any age being obviously a function of the “expected number at risk”, i.e., the expected number of survivors to the age computed on the assumption that at the earlier ages within the observations the tabular mortality had prevailed. The point has been touched upon by Mr. R. P. Hardy (J.I.A. xxxi, 253), who appears, from his remarks, to condemn the common usage in this respect. The fault would seem, however, to lie in the description “expected deaths” rather than in the method of calculating the quantity so designated—at any rate when the purpose to be served is the comparison of two experiences at individual ages.
page 284 note * The likelihood of a certain amount of difference between the aggregate rates of the three locality groups did subsequently appear, but this was due to a wholly independent cause (see pp. 295, 6).
page 295 note * In Ratcliffe's investigation of 1856-60, a comparison was made of the general tables on the bases of (1) miners included, (2) miners excluded, the difference being found to be insignificant. This result, however, was obviously due to the circumstance that the miners represented less than six per-cent of the lives at risk.
page 312 note * Sickness Benefits £1 per week for the first 13 weeks, 15s. per week for the second 13 weeks, 10s. per week for the second 26 weeks, and 5s. per week for the remainder.