1 О. Б. Шейнин Статьи по истории теории ... - Sheynin, Oscar

Yours very sincerely Simon Newcomb
Professor Karl Pearson, University College, London, England
7. Letter Pearson – Newcomb 2 Jan. 1905
Postcard in KP’s hand, no address provided, unsigned
Professor Karl Pearson 7.1 is very much obliged for your letter re
Carnegie Institute Proposals. He still considers the matter extremely
difficult of execution. He has also to heartily thank Professor
Newcomb for his memoir [1904] duly received & read. He must plead
to very great pressure on his time, if he finds himself unable to write at
length at present. He thinks, however, that the memoir might be
strengthened had it been accompanied by the probable errors of the
quantities involved.
8. Letter Newcomb – Pearson of 1 Nov., 1907 [1909]
[…] Washington D. C.
Dear Professor Pearson: – When, more than a year ago, you
published Miss Gibson’s paper in the Monthly Notices R. A. S. [Gibson
& Pearson 1908], I was minded to write you expressing my pleasure
that you were extending your statistical methods into astronomy, but
pointing out that the method adopted by Miss Gibson was not likely to
lead to any conclusive result. This, not from any inherent positive error
in the method, but from the meagreness and uncertainty of the data,
and the omission to consider relations known a priori among the
quantities classified. But I was so much occupied at the time as to be
unable to make a careful study of the paper, nor can I spare the time to
do so now. But, having noticed the recent discussion in Nature
[Pearson 1907; Hinks 1907], I venture to submit a few remarks which
you can yourself apply to the case according to your own judgement.
When we seek to find a correlation between two systems of
observed quantities, it is requisite to a certain result that the quantities
of each series be not in the nature of purely accidental ones and that
there be something we can consider definite. Examples are when either
system is the result of random sampling, or when the number of
quantities is sufficiently large to establish some law among the
magnitudes, even when purely accidental. In the case of stellar
parallaxes regarded simply as observed quantities without reference to
known conditions affecting their value, neither of these requirements is
satisfied.
My main point is that in order to reach definite results in this field,
the known relations between magnitudes, distances, and parallaxes
must be taken as the basis of the investigation. Moreover, the adopted
method must be that of trial from hypotheses, by deduction and
comparison with observations, rather than by pure induction. The
stellar universe consists of stars having definite, absolute luminosities,
distributed in space somewhat at random, and endowed with certain
absolute speeds of motion in various directions.
It seems to me the only method by which we can obtain results is
that of making hypotheses as to the several distributions, and
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