Question

In: Statistics and Probability

Create a data file frame in R called musseldata which has the following observations: species length...

Create a data file frame in R called musseldata which has the following observations:

species length drywght tidehght

calif 113 14.3 low

tross 48 6.9 med

calif 72 8.1 high

calif 82 8.7 med

tross 33 4.9 high

tross 51 7.0 med

calif 94 11.6 low

Type the name of the data frame and copy/paste your R command the result into the green box.

Use a logical condition with the subset() function to create a subset of the data called cal which contains only the observations on Mytilus californianus species (i.e. calif in the data frame). Type the name of the new data frame and the copy paste the R command you used to create the data frame, its name, and the resulting list of its contents into the green box below.

Use the order() function to create a listing of the data in the musseldata data frame sorted first by species, and within species, sorted by length. Copy/paste your R command and the resulting listing into the green box below.

Using the musseldata data frame, create a numeric vector called ratio that equals the dry weight (drywght) divided by the length. Add the ratio vector as a new variable (column) called ratio into the musseldata data frame, then type the name musseldata to display the data. Copy/paste your R commands and the resulting output into the green box below.

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orchestra answered 2 years ago

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