BOOKS OF RtfiDIfGS - PAHO/WHO

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William 1. Abernothy ond John C. Hershey
maximize or minimize a specified criterion.
tives. for a regional planuer are apparent:
Several reanonable cla~.,es of objev.
1. tMa.o.niúc utilizatiopn. Mlaximize the total utilization of prinary health
services i¡u the region, i.e., m:L(xU.
2. JlinimUize dlisiace per capita. Tlhiu criterion mighlt be represmalted i¡ two
differenit -wa:ys: ta) .\Minimize the average distaxnce that cucrlh individual in the,
comminunity mu.st travel to reachi the enter of choice. (b) .\linimize the' averag,,
dista.l'e per :apita t ttlihe (lo.s-t te iter. Tlhe latter alternative is choiiine for su.l
~.lK'uent an-:lysis. .\[athenumti('ally, tlis t.ales the form minl( E.': :,' )./b"n
:. .l litimiz,. i slitlce per c/ i. ,tinmizi the average ix.r-visit travel di.t:mn",
to tlic n(arest eenrter, where all visits as computed in equation (2) are inchlulld.
i.e.. miáiZ:-L £ - . m i,b/l'). i An alternative statemenit of thi.i ,riterion is t(i
minimiz, thi- tvf.r:ige li.st.l:,. trav.hvdil IK r visit to thel u.ier's e, t(,Lr of choice. TI,.
lirst vertsion i.s 'omsidre(d preferable for nmost applications, howvever, imice tui¡
minnimum reqluired distanve exlusçive of c*hoiec better represont.i the effeet of di.tante
ea a barrier.
4. .lin&iilize percent deleyralalion in iutilizaíion. Thisi eriterion minimize.s ¡hei
averag