With the advance in the statistical theory and method and the recent tendency toward quantitative measurements in social situations, the relationship between Political Science and Statistics has become close and deep.
The quantitative evaluation of political and administrative phenomena is regarded by political scientists as an indispensable instrument of knowledge.
The statistical approach is usually employed in conjunction with other methods. Beatrice Webb records in her autobiography, “I had learnt the relation between personal observation and statistics, though, I never acquired the statistical instrument because I had not the requisite arithmetic. I became aware that every conclusion derived from observation or experiment had to be qualified as well as verified by the relevant statistics.”
There is now a school of opinion which describes statistics as a branch of Political Science. But this is not correct. Statistics is a separate field of investigation in itself, requiring experts to make applications of the method.
Yet, it cannot be ignored that the operation of cause and effect is made convincingly concrete and definite in many instances by the use of statistics, when the ordinary methods of observation and speculation fail to give the true reality involved therein.
As Wilson observes, “While a statistical result does not provide an ethic or a norm to be embodied in policy, once the policy has been supported by rational conclusions as to what men desire of political society, statistics is invaluable in attaining the result.” Modern governments essentially depend upon the statistical material and the data it provides in solving very many political riddles.
With a Welfare State throwing its full weight on planning, statistics and its extensive use has become indispensable and every department of government keeps its own statistical cell and the administration is centred around the statistical results.
Legislation aimed at public welfare must be guided by statistics and the various aspects of the welfare of the people, for example, taxation and expenditure policy, trade, natural resources, employment, social conditions in general as vice, crime, illiteracy, population, etc., have a statistical interpretation.
Whatever be the utility of statistics and its importance in most forms of political investigation, it must be remembered that statistics may show the failure of a given political or legislative project, but it does not establish the futility of the policy.