Masters Theses


"Traffic variables, such as volume, speed, gaps and lags, and headways can be described by probability distributions. In this study vehicle arrivals from three directions have been recorded at a four-leg, right-angled, at-grade intersection in Rolla, Missouri, and statistically analyzed. Two distinct probabilistic statistical concepts were used, the continuous (gap) and discrete (counting) distribution. The negative exponential distribution is discussed briefly, whereas the applicability of discrete statistical models for the traffic situation selected is elaborated in detail.

The purpose of this research was to investigate the impairment and distortion that various interferences such as upstream traffic lights, bottlenecks or other STOP sign controlled intersections would have upon approximative discrete frequency functions.

Traffic was counted and recorded on Friday, July 7, 1972, during three two-hour time periods, in the morning, at noon, and during the afternoon rush hours. Fifteen different situations, six each for the North and West approaches, and three for arrivals from the East direction were evaluated. For the counting distribution, vehicular arrivals were grouped arbitrarily into time intervals of 30 and 60 seconds for the North approach leg, because of the slightly higher traffic volumes, 60 and 120 seconds for the West, and 120 seconds only for vehicles approaching from the East.

The “Goodness of Fit” for acceptable approximation was tested by Pearson's Chi-square for the fifteen situations described before. Then, on the basis of the mean-variance criterion, a choice was made between the binomial and negative binomial distribution. The randomness of the observed frequencies was tested against the characteristics of these distributions again by the Chi-square test and compared with the results of the Poisson fit for acceptableness or rejection of hypotheses at appropriate predetermined significance levels"--Abstract, pages ii-iii.


Josey, James L.

Committee Member(s)

Gerig, Frank A.
Rockaway, John D.


Civil, Architectural and Environmental Engineering

Degree Name

M.S. in Civil Engineering


University of Missouri--Rolla

Publication Date



viii, 74 pages

Note about bibliography

Includes bibliographical references (pages 49-51).

Geographic Coverage

Rolla (Mo.)


© 1972 Horst Walter Kaminsky, All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Roads -- Design and construction -- Research -- United States
Roads -- Interchanges and intersections -- Design and construction
Traffic flow
Traffic signs and signals -- Research -- United States
Traffic signs and signals -- Research -- United States
Distribution (Probability theory)

Thesis Number

T 2824

Print OCLC #


Electronic OCLC #



Thesis Location