Статья представляет собой несложный обзор различных подходов к построению производственных функций и обсуждение связанных с этим проблем (агрегирование и т. п.). Функции затрат рассматриваются как заменитель производственной функции, так как первые намного легче оценить на практике. Во второй части статьи автор рассматривает все наиболее значимые попытки статистического исследования произвосдтвенных функций и функций затрат.

THE PURPOSE OF THIS STUDY IS TO PROVIDE DATA AND ANALYSIS FOR A DISCUSSION OF PRIVATE CARRIAGE. THE STUDY ATTEMPTS TO ANSWER THREE QUESTIONS' 1. HOW HAS THE GROWTH OF PRIVATE ROAD HAULAGE COMPARED WITH FOR-HIRE HAULAGE AND OTHER MODES OF TRANSPORTATION{ 2. WHAT FIRMS IN WHAT INDUSTRIES AND REGIONS ARE NOW MAKING EXTENSIVE USE OF PROPRIETARY HAULAGE{ 3. WHAT ARE THE CHARACTERISTICS OF A TYPICAL FIRMS TRANSPORTATION REQUIREMENTS THAT LEAD IT TO EMPLOY PRIVATE CARRIAGE{ THE DATA WERE ANALYSED WITH THE AID OF AN ECONOMIC MODEL OF VERTICAL INTEGRATION WHICH ASSUMES THAT PROPRIETARY HAULAGE WILL BE EMPLOYED BY FIRM WHENEVER IT IS PROFITABLE FOR THE FIRM. THE HYPOTHESES THUS GENERATED WERE THEN SUBMITTED TO STATISTICAL TESTING. THIS RESEARCH WAS PERFORMED FOR THE TRANSPORTATION CENTER AT NORTHWESTERN UNIVERSITY. /RRL/