Problem description

Nine trucks with a couple hundred fish each. Each truck starts from the same location, but have a different destination across 3 years. For each truck, we have year, distance, and some water measurements. For a sample of fish, measures of stress were collected e.g. cortisol. Fish measurements were taken on different samples at times 0 (at hatchery), 2 (after arrival), 24, and 48 hrs.

Question

How can we perform an exploratory analysis on these data?

Consulting response

For an exploratory analysis, plot the fish measurements vs explanatory variables and times (or different plots for each time).

Calculate a mean and sd across the fish for each of the 36 combinations of truck and sample times. For an exploratory analysis, plot the mean (and sd) truck-time responses versus individual explanatory variables. Fit a regression model for the mean (and sd) truck-time responses versus individual explanatory variables.

Take a look at proportion of fish that died across the times as an additional measure of stress.