Getting Started with R Part 2

Question 1

walks_before <- c(79, 108, 41, 145, 135)

wanted_walks <- 100

n_seasons <- 6

walks_needed <- n_seasons * wanted_walks - sum(walks_before)

walks_needed

## [1] 92

Juan_Walks <- c(79, 108, 41, 145, 135, walks_needed)

mean(Juan_Walks)

## [1] 100

sd(Juan_Walks)

## [1] 38.20995

max(Juan_Walks)

## [1] 145

min(Juan_Walks)

## [1] 41

summary(Juan_Walks)

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   41.00   82.25  100.00  100.00  128.25  145.00

Question 2

n_1 <- 7
n_2 <- 9

y_1 <- 102000
y_2 <- 91000

salary_average <- (n_1 * y_1 + n_2 * y_2) / (n_1 + n_2)

salary_average

## [1] 95812.5

Question 3

doubles_hit <- read.csv("doubles_hit.csv")

doubles <- doubles_hit$doubles_hit

doubles_mean <- mean(doubles)
doubles_mean

## [1] 23.55

doubles_median <- median(doubles)
doubles_median

## [1] 23.5

doubles_n <- length(doubles)
doubles_n

## [1] 100

doubles_sd <- sd(doubles)
doubles_sd

## [1] 13.37371

doubles_w1sd <- sum(abs(doubles - doubles_mean) / doubles_sd < 1) / doubles_n

doubles_w1sd

## [1] 0.58

doubles_w1sd - 0.68

## [1] -0.1

doubles_w2sd <- sum(abs(doubles - doubles_mean) / doubles_sd < 2) / doubles_n

doubles_w2sd

## [1] 1

doubles_w2sd - 0.95

## [1] 0.05

doubles_w3sd <- sum(abs(doubles - doubles_mean) / doubles_sd < 3) / doubles_n

doubles_w3sd

## [1] 1

doubles_w3sd - 0.9973

## [1] 0.0027

hist(
  doubles,
  main = "Histogram of Doubles Hit",
  xlab = "Doubles Hit",
  col = "green",
  border = "red",
  breaks = 8
)