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In a recent paper, Blumenfeld [1] outlined the continuous modeling approach to the description of the joint distribution of homes and workplaces in a city. In this note, the circularly symmetric form of the quarivariate normal model is further analyzed, and distributions of the desire line lengths and other variables are derived. [ABSTRACT FROM AUTHOR]

This paper develops formulas for estimating average distances associated with zones. The average distance between two points, one located at random in a zone and another located at random in another, is first investigated. The average distance from a fixed point to a point located at random in a zone, and the average distance between two points located at random in the same zone, are also examined. The accuracy of the approximations for these average distances are found by examining some simple cases. [ABSTRACT FROM AUTHOR]

Formulas are given for determining the cost and accuracy of a given sampling scheme. Home-based, work-based and roadside surveys are examined. As in any estimation problem, one may optimize either cost or accuracy but not both. For any required accuracy, formulas are given to minimize the survey cost. It is difficult to obtain a measure of accuracy that leads to tractable mathematics; however, a formula is given that will minimize a linear combination of the sample variances of the estimators of the traffic flows. Some approximations are made that lead to simple formulas for determining the sample size. An example for a home-based survey is worked assuming preliminary estimates given by the gravity model. [ABSTRACT FROM AUTHOR]

The distribution of hourly volumes is described and its form and characteristics are discussed. Theoretical models of the distribution are derived so that an estimate of the distribution may be obtained if only a fraction of the traffic data for the year is known. Depending on the size of this sample different estimation procedures are recommended. The hour has long been the conventional counting interval used for traffic counts over long periods. Other counting intervals are considered to determine if the hour is the best unit. The distribution of daily traffic volumes is found to be best represented by a displaced gamma distribution. [ABSTRACT FROM AUTHOR]