The file sealion.csv (Source: Ahonen, H., Stow, A. J., Harcourt, R. G., & Charrier, I. (2014). Adult male Australian sea lion barking calls reveal clear geographical variations. Animal behaviour, 97, 229-239.) contains the durations (in milliseconds) of sea lion barking calls at 7 locations in Australia, namely Lewis Island, Liguanea Island, Olive Island, Blefuscu Island, Lilliput Island, North Fisherman Island, and Beagle Island.

1. [3] Read the file sealion.csv into R and run an ANOVA test.

# Hint: use read.csv("sealion.csv") to read this csv file, and make sure # your sealion.csv file is under your current working directory, # you may need to use setwd or getwd function to manipulate your workding directory 

1. [3] Is there any significant differences in the duration of sea lion barking calls across the 7 locations? Justify.
2. [2] Researcher B had already planned to test three contrasts before running the experiment. What multiple comparisons procedure would you suggest them to use?
3. [3] Using the Tukey's Honest Significance Difference (HSD), with familywise error rate controlled 5%, what do you conclude about the significance of the pair North Fisherman-Liguanea?

# Hint: consider qtukey(0.95, ...) 

e. [3] Run the Tukey's HSD using R. What pairs of locations are significantly different at the 5% familywise error rate?

# Hint: consider TukeyHSD(..., conf.level = 0.95) 

1. [3] Assess the normality of the residuals for North Fisherman Island in two ways (both visualization and formal test).
2. [3] Assess the equal variance assumption for the residuals (use a formal test).

# Hint: use funtion bartlett.test