Researchers for the North Temperate Lakes Long-Term Ecological Research program have collected fish from a number of lakes in Wisconsin since 1981. The total lengths and weights of Yellow Perch (Perca flavescens) captured from Trout Lake from 1981-2006 are recorded in YPerchTL.csv (view, download, meta). Use these data to answer the following questions. [Note that these data came from this website. See the site for more information about the sampling protocol that produced these data.]
Load these data, isolate Yellow Perch captured with only fyke nets in 2005, and answer the following questions.
- Complete this Plotting exercise.
- Describe the relationship between weight and length.
- Describe the relationship between log-transformed weight and length.
- Compute the weight-length relationship with an appropriate linear regression.
- Plot the results (data and the fitted relationship) on both the transformed and raw scales. Comment on the fit.
- Construct a residual plot. Comment.
- Express your results as an equation on the transformed scale.
- Express your results as an equation on the raw scale.
- Carefully interpret the meaning of the slope of the weight-length relationship.
- Is there statistical evidence for isometric or allometric growth?
Continue with these data for weight-length comparisons.
from Derek H. Ogle , created 09-Nov-15, updated 09-Nov-15, Comments/Suggestions.