Introduction

This activity examines whether there is a relationship between a team’s playoff finish and its regular season wins during the 2012 and 2013 MLB seasons.

Create the Team Rank Vector

teamRank <- c(1,2,3,3,4,4,4,4,5,5)
teamRank
##  [1] 1 2 3 3 4 4 4 4 5 5

Exercise 1 - 2012 Season

Create the vector of regular season wins for the 2012 playoff teams.

wins2012 <- c(94,88,95,88,93,94,98,97,93,94)
wins2012
##  [1] 94 88 95 88 93 94 98 97 93 94

Calculate the correlation.

cor2012 <- cor(teamRank, wins2012)
cor2012
## [1] 0.3477129

Interpretation

The correlation between teamRank and wins2012 is 0.3477129. This indicates a weak positive relationship between regular season wins and playoff ranking during the 2012 season.

Exercise 2 - 2013 Season

Create the vector of regular season wins for the 2013 playoff teams.

wins2013 <- c(97,97,92,93,92,96,94,96,92,90)
wins2013
##  [1] 97 97 92 93 92 96 94 96 92 90

Calculate the correlation.

cor2013 <- cor(teamRank, wins2013)
cor2013
## [1] -0.6556945

Interpretation

The correlation between teamRank and wins2013 is -0.6556945. This indicates a moderately strong negative relationship between regular season wins and playoff ranking during the 2013 season.

Summary

results <- data.frame(
  Season = c("2012", "2013"),
  Correlation = c(cor2012, cor2013)
)

results

Conclusion

The 2012 season produced a positive correlation, while the 2013 season produced a negative correlation. Since the direction of the relationship changes between the two seasons, there is no consistent evidence that regular season wins predict playoff success based on these data alone.