Directions

The objective of this assignment is to introduce you to R and R markdown and to complete some basic data simulation exercises.

Please include all code needed to perform the tasks. This is an R Markdown document. Markdown is a simple formatting syntax for authoring HTML, PDF, and MS Word documents. For more details on using R Markdown see http://rmarkdown.rstudio.com.

To submit this homework you will create the document in Rstudio, using the knitr package (button included in Rstudio) and then submit the document to your Rpubs account. Once uploaded you will submit the link to that document on Canvas. Please make sure that this link is hyperlinked and that I can see the visualization and the code required to create it.

Questions

  1. Simulate data for 30 draws from a normal distribution where the means and standard deviations vary among three distributions.
# place the code to simulate the data here
set.seed(16)
rnorm(30, mean = c(50,5,20), sd=c(1,5,20))
##  [1]  50.476413   4.373100  41.924324  48.555771  10.739146  10.631759
##  [7]  48.994049   5.317813  40.499452  50.573142  14.235911  22.238667
## [13]  49.253963  13.291068  34.434411  48.336920   7.879548  29.455202
## [19]  49.457268  10.638435 -12.955952  49.685826   4.086592  49.409570
## [25]  49.134101  12.637335  41.083561  51.030071   9.200804  24.339294
  1. Simulate 2 continuous variables (normal distribution) (n=20) and plot the relationship between them
# place the code to simulate the data here
x= rnorm(20, mean = 0, sd =1)
y= rnorm(20, mean = 0, sd =1)
plot(y~x)

  1. Simulate 3 variables (x1, x2 and y). x1 and x2 should be drawn from a uniform distribution and y should be drawn from a normal distribution. Fit a multiple linear regression.
# place the code to simulate the data here
x1 = runif(100, min =1, max = 2)
x2 = runif(100, min = 200, max = 300)
y = rnorm(100, mean = 0, sd = 1)
model = lm(y~ x1+x2)
plot(model)

  1. Simulate 3 letters repeating each letter twice, 2 times.
# place the code to simulate the data here
rep(letters[1:3], each = 2, times =2)
##  [1] "a" "a" "b" "b" "c" "c" "a" "a" "b" "b" "c" "c"
  1. Create a dataframe (n = 27) with 3 groups, 2 factors and two quantitative response variables. Use the replicate function.
# place the code to simulate the data here
simlist = replicate(n = 27, expr = data.frame(group = rep(letters[1:3], each = 2),factor = rep(LETTERS[3:4],each=3), response = rep(1:2,2,each =3)),simplify = FALSE)
str(simlist)
## List of 27
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...
##  $ :'data.frame':    12 obs. of  3 variables:
##   ..$ group   : Factor w/ 3 levels "a","b","c": 1 1 2 2 3 3 1 1 2 2 ...
##   ..$ factor  : Factor w/ 2 levels "C","D": 1 1 1 2 2 2 1 1 1 2 ...
##   ..$ response: int [1:12] 1 1 1 2 2 2 1 1 1 2 ...