Lab 05: Paired Data t-test

Use the dataset finches. Download the data and save the CSV file into your Lab05 directory (so that it is submit when you upload your Lab05 folder). Load the dataset into R.

Read the help file about finches, to better understand the data set.

Please submit a folder containing your Quarto input (qmd) and output (html) documents for this lab, named Lab05, to our shared Google Drive folder when you are finished.

Compare finches beakheight to beakwidth.

  1. Make a scatter plot of the two numerical variables. Add to your plot geom_abline(slope = 1) to help your eye visualize where on the plot finches with equal beakheight and beakwidth are.

  2. State one interesting thing about your plot in context of the data.

  3. Make a 90% confidence interval for the mean difference in beak height and beak width.

  4. Interpret your confidence interval in context of the data.

  5. State more clearly what your confidence interval suggests about the mean difference between beakheight and beakwidth.

  6. Perform a hypothesis test of these paired data, using a level of significance that appropriately matches your confidence interval above. Please state your hypotheses.

  7. Based on your test, which hypothesis is more likely given the data? State your conclusion as either “reject H0” or “fail to reject H0”, and explain why this conclusion is appropriate.

  8. Interpret in context of the data your conclusion of the hypothesis test.

  9. State more clearly what your hypothesis test suggests about the data.

  10. Conjecture why your conclusion might be biologically meaningful.