In Chapter 3, Assignment Problem 23, you produced a box plot for the following data from Norton et al. (2011). The data are measurements of the amount of time, in seconds, that individual zebrafish with and without the spiegeldanio (spd) mutation at the Fgfr1a gene spent in aggressive activity over 5 minutes when presented with a mirror image of themselves. The researchers were interested in the role this gene plays in differences between individuals along the shy–bold behavioral spectrum.

a. With these data, estimate the magnitude of the effect of the mutation (the difference between the means) on the amount of time spent in aggressive activity. Put appropriate bounds on your estimate of the effect.

b. Perform an appropriate statistical test of the difference in mean aggressive activity between these genotypes.

Data from problem

As in other vertebrates, individual zebrafish differ from one another along the shy–bold behavioral
spectrum. In addition to other differences, bolder individuals tend to be more aggressive, whereas shy individuals tend to be less aggressive. Norton et al. (2011) compared several behaviors associated with this syndrome between zebrafish that had the spiegeldanio (spd) mutant at the Fgfr1a gene (reduced fibroblast growth factor receptor 1a) and the “wild type” lacking the mutation. The data below are measurements of the amount of time, in seconds, that individual zebrafish with and without this mutation spent in aggressive activity over 5 minutes when presented with a mirror image.

Transcribed Image Text:

Spd mutant: 96,96, 97,97, 100, 100, 127,127, 128,128, 156,156, 162, 162, 170,170, 190,190, 195195