In 
vy 
THE STATISTICAL VERIFICATION OF 
it is as a contribution to it that I have written this 
paper.’ ! 
This is not the place for an assessment of the value of 
Booth’s statistical conclusions from his examination into 
the conditions of London life, nor their influence in 
correcting current conceptions of fact and tendency, nor 
the remoter reactions on social and economic theory. 
An interesting and sufficient account may be found in 
Mrs. Sidney Webb’s autobiography, My Apprenticeship. 
Booth’s questions were hardly those of a theoretical or 
academic economist, but his method of ad hoc inquiry 
to test theories of social betterment were the forerunners 
of the specific investigation of later days. 
II. Modern Developments in Exposition of Theory. 
Professor Marshall’s volume on Principles may be 
taken as the great example of exposition of economic 
theory on lines new thirty-six years ago and hardly yet 
superseded. It is interesting to examine its dependence, 
not so much upon statistical illustration as upon statis- 
tical verification. There are several tables (population, 
growth of wealth, &ec.) used to aid the descriptive por- 
tions. When dealing with the nature of the ‘ demand 
curve’ and ‘elasticity ’, he refers to the study of exact 
lists of demand prices and to the difficulty of interpreting 
them, but he gives no examples, and indicates diagram- 
matically how to observe percentage increases over a 
period of years, or the rate of growth. He thinks that 
the statistics of consumption published by governments 
for many commodities are of very little service in help- 
ing inductive study, but elaborates the hint given in 
Jevons’ theory that traders could further it greatly by 
analysing their own accounts’. ‘If a sufficient number of 
tables by different sections of society could be obtained, 
they would afford the means of estimating indirectly 
1 Condition and Occupations of the People of the Tower Hamlets, 
1886-7, by Charles Booth, 1887, p. 7.