A quadratic polynomial as a nonlinear model (Data file: swan96) The data were collected by the Minnesota Department of Natural Resources to study the abundance of black crappies, a species of fish, on...

A quadratic polynomial as a nonlinear model (Data file: swan96) The data were collected by the Minnesota Department of Natural Resources to study the abundance of black crappies, a species of fish, on Swan Lake, Minnesota in 1996. The response variable is LCPUE, the logarithm of the catch of 200 mm or longer black crappies per unit of fishing effort. It is believed that LCPUE is proportional to abundance. The single predictor is Day, the day on which the sample was taken, measured as the number of days after June 19, 1996. Some of the measurements were taken the following spring on the same population of fish before the young of the year are born in late June. No samples are taken during the winter months when the lake surface was frozen.