1 Studies in the History of Statistics and Probability ... - Sheynin, Oscar

But then the newly appearing peculiarities of that material will havenot been noticed.What kind of peculiarities could happen? For example, on Fig. 2aand 2b a certain non-zero number of observations is shown in theregion µ* ≤ − 3. The probability of one observation being there(assuming that the Mendelian laws are valid) is 0.0014, and, of one outof approximately a hundred (to recall, the numbers of observationswere 98 and 123), about a hundred times higher; here, almost preciselyso. Thus, the probability of observations appearing in that region inboth series is about 0.14 2 ≈ 0.02, which means that a deviation fromnormality N(0, 1) is significant on the level ≈ 2%. So, are theMendelian laws nevertheless wrong? Well, first of all, we have chosena test corresponding to known data; second, a perfectly reasonableattitude does not mean dogmatically following tests of significance. Areasonable answer apparently means that the bulk of observationsperfectly agrees with the Mendelian laws but sharp deviations perhapsdo occur. It can be supposed that a deficiency in the number ofdisplayed recessive indications has some biological sense (if,according to a very simple explanation, there exists a connection withsurvivorship).Incidentally, the above sufficiently illustrates the simple idea thattruth in science is established by the work of a number of generationsand is not always attained at each separate investigation.2.2. No one knows the hour ... The ancient saying, No one knowsthe hour of his death, became somewhat shaken (certainly in thestatistical rather than individual sense) after life tables have beencompiled and it occurred that the probability of living up to a definiteage, is subject to fluctuations (depending on the conditions of life),which are, however, not too essential. A further step towards anindividual forecast based on multivariate statistical analysis is partlymade and partly being made. I am describing one of the mostoutstanding contributions in this field, the so-called Framinghaminvestigation (one of the pertinent publications is Truett et al 1967).The cardiovascular diseases are known to be one of the centralproblems of modern medicine. They are manifested in different ways;one of the most common kind is the so-called ischemic heart disease(IHD). According to the classification adopted in the cited work, itcomprises cases of myocardial infarction, coronary insufficiency,angina pectoris and deaths occasioned by disturbances of the coronaryblood circulation. We know well enough that the IHD often affectspeople yet being in the prime of creative power which makes theproblem especially acute.There exist some rather vague ideas on the part played by the factorsof modern industrialized life in the development of the IHD (littlephysical activity, nervous-emotional stress, irrational diet, etc) andalso by the possible influence of genetic factors. These ideas arecertainly extremely important but we would like to have, in addition togeneral (but insufficiently clear and incompletely proven) ideas someamount of scientific (i. e. trustworthy) information.That, perhaps not covering the entire problem, would provide areliable foundation for some practical conclusions. Important is, for106