The ecological consequences of climate change and its interaction with other environmental pressures, such as nutrient pollution, are little understood. For freshwater ecosystems, knowledge of these combined effects is required for water resource management and in particular for successful...

This paper provides a test of monotonicity of a regression function. The test is based on the size of a "critical" bandwidth, the amount of smooting necessary to force a nonparametric regression estimate to be monotone. It is analogous to Silverman's test of multimodality in density estimation.