Inch Lake

Examine relative weight as a measure of condition for Inch Lake Bluegill.
Relative Weight

Derek H. Ogle


Mar 8, 2019


Dec 27, 2022


This exercise is a continuation of this data wrangling exercise and, thus, depends on data frames constructed there. Please load/run your script from that exercise to access the Bluegill only data frames.


Basic Analysis I

Further prepare the Bluegill only data frame for computation of relative weights by adding a relative weight variable and reducing the data frame to only fish with lengths for which a standard weight should be computed.

  1. For Bluegills captured only in 2007
    1. Compute the number of observations and mean, standard deviation, and standard error of relative weight for each Gabelhouse length category.
    2. Determine if the mean relative weight differs among Gabelhouse length categories.
    3. Construct a plot, with confidence intervals and appropriate significance letters, that depict your results.


Basic Analysis II

  1. Repeat the previous question for Bluegills captured only in 2008.
  2. Empirically compare your results between years. Provide at least three observations from your findings and at least two plausible explanations for what you observed.


Solution Code:

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