Question: Many studies have documented a clear pattern of climate change towards warmer temperatures globally. A survey of the North Sea over a 25 year period from 1977-2001 was focused on whether, as sea winter temperatures have warmed up, fish populations have moved further North. Here are the data for mean winter bottom temperature and mean northern latitude of anglerfish populations each year over the 25 year study period.

a) Do a scatterplot of the Latitude of the fish stocks versus Temperature. Describe what you can conclude from this plot. [3]

b) Perform a regression analysis on Latitude versus Temperature, including a Residuals versus Fits plot. Give a full analysis. [6]

c) Perform a regression in the alternative way, by finding Temperature as a function of Latitude of the fish stocks, including a residuals versus fits plot. Remove the data for the point (59.06, 6.32) that could be regarded as an outlier. Perform the regression again. In both cases, do not bother with the hypothesis testing. Which do you view as the better model? [4]