This paper examines changes in agricultural productivity in 18 developing countries over the
period 1961–1985. We use a nonparametric, output-based Malmquist index and a
parametric variable coefficients Cobb–Douglas production function to examine, whether our
estimates confirm results from other studies that have indicated declining agricultural
productivity in LDCs. The results confirm previous findings, indicating that at least half of
these countries have experienced productivity declines in agriculture.

Nonparametric productivity analyses performed to date show that most developing countries
are experiencing relatively rapid technical regress in agriculture. We discuss the plausibility
of these results and argue that they stem from the existence of biased technical change and
the definition of technology used. We reestimate the Malmquist index for a group of
developing countries using a different definition of technology and find that most developing
countries in our sample are experiencing positive productivity growth with technical change …