The daily morning journal and courier. [volume] (New Haven, Conn.) 1894-1907, 1897-03-20

Lecture IN Shemeld CourSe-COmnOn MIS-
takes of Census Takers-SOme Striking
Examples of Errors-Edward Atkinson
Facts Presented.
Labor Commissioner Carroll D.
Wright is credited with the remark
that Figures don't lie,' but liars will
figure" Prof. Arthur II. Hadley, be-
fore large audience in the Sheffield
lecture course last evening, showed
how many fallacious results were OBJ
tained by many who count themselves
experts in the manipulation of figures
Speaking on the use and Misuse of
Statistics" Prof Hadley said in part:
ut is a common error to suppose that
by taking a large enough number of
men and striking an average we can
determine the normal types of people,
and the normal ways of doing various
things. We may roughly classify sta
tistical errors into fallacies of enumer-
alton and fallacies of inference. Fal-
lacies of enumeration arise out of the
attempt to express by means of figures
what it is impossible thus to express.
II is very much like what has been said
of the Concord school of philosophy,
that 1t 'scrutes the inscrutable and
posses the impossible
An example of this kind of fallacy
is that of a statistician who estimated
that the average man drank 271 kinds
of liquor. OF course this is absurd. 1t
is like the newspaper report of an ac-
cident which stated that it was quite
bad accident, and three or four were
killed.
Another cause of mistake of enumer-
alton is where the inquiries on which
the enumerations are based are all right
but the enumerations themselves are
inefficient. An example of this kind
occurred in New York some time ago
when it was desired~to ascertain the
number of unemployed persons in the
city The Columbia college students in
| terested in the statistics offered to do
| the work, but the police authorities
| thought they would prefer to do it
themselves. Accordingly each police
man was ordered to fill out blank
| form for every family on his heat, as
to the number in the family, number
| ordinarily employed and now out of
| work The students of the college were
| requested to tabulate these reports, and
| they had plenty of fun. Here are spec
| iments of the way the blanks were fill
ed out by the policemen:
| Number in the family ly.............. 10
| ill
| Number out OF work ................ Z
Another
| Number In family. ................. 300
Ordinarily employed. d................ 0
| Now out of work. Observation-Disclosures. 300
Note: This family is an orphan asy-
| lum.
Few people have any idea of statisti
cal theory. They think if they base
their estimates ON 100 persons they get
a good average. If they take all the
people they get correct average. Now,
this is, of course fallacy. An ex-
ample of this is found in the estimates
based on the budgets of workingmen's s
expenditures. Many of the working
| men keep no account of their expen-
| ditures and those that do are of the
more intelligent class, so that any es-
| innate based on the statistics must be
based on the budgets of the working
| men who are most intelligent and
would not be accurate for the entire
laboring class.
"The same is true in all labor and
wage statistics which are of necessity
based on the answers of the most intel
ligent laborers who are the most ac-
cessible.
"Another example of this was the all
absorbing question last fall as to wheth-
er gold had been appreciating or depre-
ciating in value. Many would take a
large number of articles, and taking
the per cent of increase or decrease,
would strike an average of the whole.
This would not give a true result, for
one article of merchandise, which
would be sold perhaps in great quanti-
ties, would be counterbalanced by an
other sold in much smaller quantities.
Suppose, for example, pepper had ad-
vanced in value to ITO per cent. of its
former price, and wheat, on the other
hand, had shrunk to so per cent. of its
former value. An average made of the
two would show an average of 95 per
cent of its former value, which. of
course, would not be accurate. consid-
ering the much larger quantities of
wheat than pepper which are sold
What scientific statistcians are now
doing is not to base their estimates up
on so large g number of articles, but
to take a few and study the circum-
stances in connection with these care
fully.
"Fallacies of ignorance are authenti-
cal and logical, authentical fallacies be-
ing the result of adding and subtract
ing figures not made up in the same
way and logical fallacies resulting from
the reasoning processes.
"An example of authentical fallacy is
that found in the estimates of the cap
italization of railroads. 1t is remarka-
BILE that in this matter the statistician
of the interstate commerce commission
does not know the true capitalization
of the railroads of the United States
and it is not given properly in Poor's
or any of the other manuals The error
lies in this: Taking the number of miles
of road at 100000, they divide the total
stock and bond amounts of the rail.
roads by it and get a capitalization OF
$50, 900 per mile, which is about SO O0(
too much.
This error results from the reckon.
ing into the capitalization of one road