Elimination of Source A and B Errors in p-Median Location Problems

The p-median problem is a powerful tool in analyzing facility location options when the goal of the location scheme is to minimize the average distance that demand must traverse to reach its nearest facility. It may be used to determine the number of facilities to site, as well as the actual facility locations. Demand data are frequently aggregated in p-median location problems to reduce the computational complexity of the problem. Demand data aggregation, however, results in the loss of locational information. This loss may lead to suboptimal facility location configurations (optimality errors) and inaccurate measures of the resulting travel distances (cost errors). Hillsman and Rhoda (1978) have identified three error components: Source A, B, and C errors, which may result from demand data aggregation. In this article, a method to measure weighted travel distances in p-median problems which eliminates Source A and B errors is proposed. Test problem results indicate that the proposed measurement scheme yields solutions with lower optimality and cost errors than does the traditional distance measurement scheme.     

PREHISTORIC FLINT MINES AND THEIR IDENTIFICATION AS SOURCES OF RAW MATERIAL

This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed.     

Reviews of books

Historical Archaeology -     

Book reviews

Australian books

D. C. Dunphy, Cliques, Crowds and Gangs: Group Life of Sydney Adolescents, Cheshire, Melbourne, 1969, pp. 170 + xi, $4.50.

A. A. Congalton, Status and Prestige in Australia, Cheshire, Melbourne, 1969, pp. 160 + xvi, $7.50.

B. R. Davidson, Australia Wet or Dry? The Physical and Economic Limits to the Expansion of Irrigation, Melbourne University Press, Melbourne, 1969, pp. 264 + xiv, S3.60 (paperback), $6.60 (hard cover).

Brian Dickey (ed. and intro.), Politics in New South Wales 1856–1900, Problems in Australian History series, Cassell Australia, Melbourne, 1969, pp. 200 + xv, $3.25.

K. L. Needham, Charles Hawker, Forlib Books, Adelaide, 1969, pp. 165 + xiv, $4.85.

Edward St. John, A Time to Speak, Sun Books, Melbourne, 1969, pp. 280, $1.65.

Egon F. Kunz, Blood and Gold: Hungarians in Australia, Cheshire, Melbourne, 1969, pp. 240, $7.50.

H. Throssell (ed.), Ethnic Minorities in Australia: The Welfare of Aborigines and Migrants, Australian Council of Social Service, Sydney, 1968, pp. 184 + viii, $3.75.

Marnie Bassett, Letters from New Guinea 1921, Hawthorn Press, Melbourne, 1969, pp. 159 + x, $5.50.

Ken Turner, House of Review? The New South Wales Legislative Council, 1934–68, Sydney Studies in Politics, No. 8, Sydney University Press, 1969, pp. 164 + viii, $5.00.

Colin A. Hughes, Images and Issues: The Queensland State Elections of 1963 and 1966, Australian National University Press, Canberra, 1969, pp. 364, $7.95.

Non‐Australian Books

Miles Copeland, The Came of Nations: The Amorality of Power Politics, Weidenfeld and Nicolson, London, 1969, pp. 272, $6.65.

Kenneth N. Waltz, Foreign Policy and Democratic Politics: The American and British Experience, Longmans, London, 1968, pp. 331 +xii, $4.70.