The adoption of the quantitative methods in Political Science has been facilitated by the invention and use of the new devices and techniques for collecting facts or data, storing and retrieving than, which are significantly called the “data revolution”. They are various kinds of electronic devices and techniques, the punch-card machines, and above all, various kinds of computers, and data banks.
Since 1945, Political Science has been transformed by the availability of these devices and techniques of collection, storage and retrieval of the huge amounts of data, which have made quantitative analysis and study of political events and processes not only easier but also more reliable.
They are particularly useful in such fields of political life as election forecasts, pollstering, personality studies of political leaders and elites, legislatures, bureaucracies, etc. It may be mentioned that these quantitative methods have enabled political scientists to begin the behavioural movement after 1950, which became the dominant method of political analysis for the next two decades in the U.SA.
The quantitative methods have, however, one drawback: these are very expensive methods. These are more predictive and, therefore, have made Political Science less speculative, but more scientific.