11

checked against what would be expected in a perfect market. Their conclu-

sions were that, "average seasonal price movements correspond rather well

with the cost of storage; that intermarket price correlations were somewhat

less than might be hoped for; that year-to-year price movements were generally

in accord with supply and marketing conditions; but that week-to-week price

changes showed signs of serious random disturbances consistent with the

hypothesis that traders were poorly informed about episodic changes in the

conditions of supply and transport"---"In terms of the tasks that marketing

systems are asked to perform, the African ones that we studied are not

performing badly" (15). Despite this assessment of the existing marketing

system, Jones points out the critical need for attention to marketing in

economic development planning where major technological and institutional

changes are being contemplated. Jones closes his article with the observa-

tion that, "the invisible hand cannot be trusted completely to guide

economies in socially acceptable directions, nor can the state rely on the

marketing system to perform the tasks assigned to it without appropriate

facilitating services best provided by government" (15).

 A major problem with the research framework developed in most of these

diagnostic assessments is the lack of concern for the dynamic impacts which

marketing services can have both on production and consumption. The static

focus of the research has been on whether prices and cost relationships over

space and time behave as predicted by the perfectly competitive model.

Relatively little effort had been made to better understand how the effective-

ness of marketing services influences supply and demand functions, especially

for small scale farmers and low income consumers.