Module 3: Follow That Seal

Overview

With the aquaponics system compromised, the team must turn to wild-caught fish to supplement their food supply, but fishing in Antarctic waters comes with risks. Leopard seals are apex predators in the area, and the radio collars used to track them have been failing unexpectedly. Students are tasked with figuring out which collar manufacturer is to blame by comparing means numerically, visually, and statistically, first using t-tests to compare two groups, then extending to ANOVA and post-hoc comparisons when more than two groups are involved. By the end of the module, students can determine whether differences between groups are statistically meaningful and apply these tools to new ecological contexts.

Learning Objectives

By the end of this module, students will be able to:

  • explain the logic of hypothesis testing, including null and alternative hypotheses
  • distinguish between independent and dependent variables and identify each in a research question
  • determine when a t-test versus an ANOVA is the appropriate statistical test
  • run a t-test using the t.test() function and interpret the output, including t-value, p-value, and confidence interval
  • run a one-way ANOVA using the aov() and summary() functions and interpret the F-value and p-value
  • run a Tukey’s HSD post hoc test using TukeyHSD() and interpret pairwise comparisons
  • add a vertical reference line to a ggplot2 plot using geom_vline()

Lessons & Assignments

Lessons

Lesson QMD Data Files
3.1: Intro to Linear Regression Download collar_data.csv
3.2: More Linear Regression Download collar_data.csv
3.3: ANOVA and Comparisons Download more_collars.csv

Assignments

Assignment QMD Data Files Outputs
M3A1: Wind Turbine Analysis Download wind_turbines.csv Download
M3A2: Comparing Fish and Seal Populations Download fish.csv, seals.csv Download

GitHub

To clone the entire course, visit the course GitHub repository.