PROFICIENT YEARS AT SPORTS

going hypothesis is a valid one. And, if valid, it will be possible to
determine, for groups of individuals, which particular chronological age
level, or fraction thereof, is most propitious both for the specific types
of behavior that have been mentioned herein and for many others
as well.

It seems obvious that, in much of the unorganized competition that
is constantly taking place between the various age groups, some of the
age groups are greatly handicapped, others of them are slightly handi-
capped, and some, perhaps only one, at any rate not more than a very
few, possess a distinct advantage. And the keener the competition, the
more valid, within limits, the foregoing statements. It seems likely that
future generations of psychologists may be able to express these facts
with mathematical precision. Indeed, it should be possible to construct,
for each specific type of measurable behavior, of a given standard of
excellence, something analogous to the mortality tables that have long
been utilized by life insurance companies. Like the mortality tables, the
probability tables that are here suggested would apply only to groups
of individuals of a given chronological age. Such tables obviously
would not apply to every individual within a given age group.

BIBLIOGRAPHY

I. (a) Lehman, H. C., “The Creative Years in Science and Literature,” The

Scientific Monthly, 43 (1936) 151-162.

(b) Heidler, J. B., and H. C. Lehman, “Chronological Age and Productivity:
Various Types of Literature,’ The English Journal, (College Edition)
27 (1937) 294-304.

(c) Lehman, H. C., “The Creative Years: ‘Best Books,’” The Scientific
Monthly, 45 (1937) 65-75.

(d) Lehman, H. C., and D. W. Ingerham, “The Creative Years in the Field
of Music,” The Scientific Monthly, 47 (1938) (Forthcoming).

2. Menke, F. G., All Sports Record Book, (New York: All Sports Record Book,
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3. Who’s Who in Baseball, (New York: Baseball Magazine Co., annual).

4. Romano, J. J. (Editor), Post Boxing Record and Sports Annual for 1935,
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5. Hendy, J. D. (Editor), Official National Hockey Guide for 1935, (New York:
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6. (a) Johnson, Harold (Speed), and Wilfrid Smith, Who’s Who in Major League

Football, (Chicago: B. E. Callahan, 328 South Jefferson Street, 1935)
94 pages.

(b) Johnson, Harold (Speed), Who’s Who in Major League Football, (Chi-
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4. Birth, Stillbirth, and Infant Mortality Statistics for the Birth Registration
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8. Billiards Magazine: Official Organ of the National Billiards Association of
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