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 Moodle. 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.
set.seed(1)
rnorm(30, mean=c(1,5,15), sd=c(1,10,50))
##  [1]   0.3735462   6.8364332 -26.7814306   2.5952808   8.2950777
##  [6] -26.0234192   1.4874291  12.3832471  43.7890676   0.6946116
## [11]  20.1178117  34.4921618   0.3787594 -17.1469989  71.2465459
## [16]   0.9550664   4.8380974  62.1918105   1.8212212  10.9390132
## [21]  60.9488686   1.7821363   5.7456498 -84.4675848   1.6198257
## [26]   4.4387126   7.2102247  -0.4707524   0.2184994  35.8970780
  1. Simulate 2 continuous variables (normal distribution) (n=20) and plot the relationship between them
set.seed(2)
{x=rnorm(20,10,1)
y=rnorm(20,5,2)
plot(x,y)}

  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.
set.seed(3)
{
  x1=runif(20,0,100)
  x2=runif(20,50,100)
  y=rnorm(20,0,10)
  z=lm(y~x1+x2)
  z
  
}
## 
## Call:
## lm(formula = y ~ x1 + x2)
## 
## Coefficients:
## (Intercept)           x1           x2  
##     -2.2102      -0.1276       0.1325
  1. Simulate 3 letters repeating each letter twice, 2 times.
set.seed(4)
{
  rep(letters[4:6],each=2, times=2)
}
##  [1] "d" "d" "e" "e" "f" "f" "d" "d" "e" "e" "f" "f"
  1. Create a dataframe with 3 groups, 2 factors and two quantitative response variables. Use the replicate function (n = 25).
set.seed(5)
{
z=replicate(n=25,expr=data.frame(group=rep(LETTERS[1:3]),factor(letters[1:2]),x=rnorm(12,5,1), y=rnorm(12,0,3)),simplify = FALSE)
z
}
## [[1]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.159145 -3.2411778
## 2      B                    b 6.384359 -0.4726031
## 3      C                    a 3.744508 -3.2152801
## 4      A                    b 5.070143 -0.4169584
## 5      B                    a 6.711441 -1.7919393
## 6      C                    b 4.397092 -6.5519003
## 7      A                    a 4.527834  0.7224518
## 8      B                    b 4.364629 -0.7780662
## 9      C                    a 4.714226  2.7015358
## 10     A                    b 5.138108  2.8256082
## 11     B                    a 6.227630  4.4038857
## 12     C                    b 4.198221  2.1202833
## 
## [[2]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 5.819009 -3.0285979
## 2      B                    b 4.706518 -6.0014182
## 3      C                    a 6.418589 -5.2865576
## 4      A                    b 6.498774 -0.4278244
## 5      B                    a 4.342918  4.6501811
## 6      C                    b 4.147205 -2.4072695
## 7      A                    a 5.315915 -0.2237368
## 8      B                    b 6.109694  5.6870039
## 9      C                    a 7.215461 -1.3697068
## 10     A                    b 6.217104  1.6866701
## 11     B                    a 6.479222 -2.6610255
## 12     C                    b 5.951574 -1.3807337
## 
## [[3]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.275672 -3.4097484
## 2      B                    b 4.930789  2.5644913
## 3      C                    a 6.463249 -1.7351113
## 4      A                    b 5.187726  1.4890846
## 5      B                    a 6.022023 -2.2801738
## 6      C                    b 4.408165 -1.0241588
## 7      A                    a 4.887799 -6.3069874
## 8      B                    b 4.075047 -0.9051068
## 9      C                    a 5.753305 -3.8171503
## 10     A                    b 4.887391 -0.8389983
## 11     B                    a 4.935909 -0.6122920
## 12     C                    b 5.233275 -0.6768426
## 
## [[4]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 5.347028  2.0270534
## 2      B                    b 5.032368 -2.1309288
## 3      C                    a 5.413531  7.1616979
## 4      A                    b 4.844652 -1.4202960
## 5      B                    a 5.973485 -0.2273177
## 6      C                    b 5.121090 -1.5655202
## 7      A                    a 5.189174  2.7781414
## 8      B                    b 4.437115 -3.1872335
## 9      C                    a 5.498416  1.6711016
## 10     A                    b 3.257698  2.7021918
## 11     B                    a 5.975529  2.9698371
## 12     C                    b 4.975917  1.1508243
## 
## [[5]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.653416 -2.2605313
## 2      B                    b 4.459811  3.8404549
## 3      C                    a 4.817444 -2.8587149
## 4      A                    b 4.940700  4.8671382
## 5      B                    a 3.004613  7.8004261
## 6      C                    b 6.135311  0.4189455
## 7      A                    a 5.675795 -4.0521590
## 8      B                    b 5.208483  2.3967931
## 9      C                    a 4.942154 -4.6649875
## 10     A                    b 5.893811  1.3911602
## 11     B                    a 4.771135  0.1572887
## 12     C                    b 3.034347 -0.6060954
## 
## [[6]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 6.170856 -3.72285175
## 2      B                    b 5.884845 -0.31211738
## 3      C                    a 3.682111  2.19891888
## 4      A                    b 3.356749  1.36703887
## 5      B                    a 6.059250  0.86423864
## 6      C                    b 5.290084 -3.22107273
## 7      A                    a 4.599967  1.94622762
## 8      B                    b 6.243096  0.89748684
## 9      C                    a 3.633589 -2.38798498
## 10     A                    b 3.558587 -0.08806019
## 11     B                    a 6.348549  6.54070710
## 12     C                    b 3.021472  2.87225541
## 
## [[7]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.694951 -1.0142854
## 2      B                    b 4.581597  3.5890991
## 3      C                    a 5.099954 -1.3299551
## 4      A                    b 4.770190  0.5583447
## 5      B                    a 3.584785 -7.8640344
## 6      C                    b 4.607401  6.7387639
## 7      A                    a 5.946089  0.2802950
## 8      B                    b 5.751771  4.8818403
## 9      C                    a 4.482623 -1.5327526
## 10     A                    b 5.808336 -1.9781425
## 11     B                    a 4.385465 -0.1205705
## 12     C                    b 6.238259 -0.3560820
## 
## [[8]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.980343  6.5449400
## 2      B                    b 4.514322 -2.0513199
## 3      C                    a 3.559852  2.2501776
## 4      A                    b 5.143769  2.9231479
## 5      B                    a 3.765413 -3.7934204
## 6      C                    b 3.247499 -0.8322643
## 7      A                    a 4.964504 -0.5681961
## 8      B                    b 5.332035 -1.1520748
## 9      C                    a 6.572288  2.2217641
## 10     A                    b 3.930529 -3.5050152
## 11     B                    a 5.916287  2.0026161
## 12     C                    b 4.405007  1.0987108
## 
## [[9]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.485057  0.8276948
## 2      B                    b 5.450568  1.2323449
## 3      C                    a 4.812280  1.8335495
## 4      A                    b 6.339069  2.8097122
## 5      B                    a 5.816219 -1.1026251
## 6      C                    b 5.082202  2.2211303
## 7      A                    a 4.349137  3.6555992
## 8      B                    b 5.726409  1.8874033
## 9      C                    a 4.886322  1.5832389
## 10     A                    b 4.704899 -1.4167659
## 11     B                    a 5.989168  2.4711455
## 12     C                    b 4.224868 -1.2833647
## 
## [[10]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 4.857356  -2.6523070
## 2      B                    b 6.418783 -10.4941770
## 3      C                    a 5.487134  -1.1459501
## 4      A                    b 5.603441   2.9330644
## 5      B                    a 5.210833  -1.6741228
## 6      C                    b 4.966701  -1.8793654
## 7      A                    a 7.025197  -1.5913537
## 8      B                    b 4.629213   5.6928648
## 9      C                    a 3.421766   4.1866220
## 10     A                    b 4.878428  -2.2380776
## 11     B                    a 3.203323  -0.9167192
## 12     C                    b 4.524408   3.5090345
## 
## [[11]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 5.304387  0.49246787
## 2      B                    b 4.882502 -1.18037684
## 3      C                    a 4.939914 -5.53121174
## 4      A                    b 6.470939 -4.62686480
## 5      B                    a 3.521852 -1.75872108
## 6      C                    b 4.316387 -2.55641673
## 7      A                    a 5.460541  2.33497367
## 8      B                    b 4.818498 -0.09095122
## 9      C                    a 3.841184 -4.36697275
## 10     A                    b 5.409019  0.28135477
## 11     B                    a 4.741793  2.94704767
## 12     C                    b 4.733101 -1.79013049
## 
## [[12]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 5.074805 -4.03132573
## 2      B                    b 7.197429  0.45388210
## 3      C                    a 5.795023  0.87002738
## 4      A                    b 4.461058 -0.36743498
## 5      B                    a 3.398717  0.37546316
## 6      C                    b 4.268626 -2.31730234
## 7      A                    a 4.644259 -3.03889837
## 8      B                    b 4.014586  2.90075880
## 9      C                    a 4.268829 -1.26998190
## 10     A                    b 6.465324 -2.49479836
## 11     B                    a 6.858615  4.19987180
## 12     C                    b 5.003497  0.05104188
## 
## [[13]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 6.847497  3.6304383
## 2      B                    b 4.313661  0.5659715
## 3      C                    a 4.781276  5.8874960
## 4      A                    b 5.682593  0.4161358
## 5      B                    a 5.524130 -4.7358821
## 6      C                    b 5.080550 -2.3910638
## 7      A                    a 5.053786  3.6730616
## 8      B                    b 4.262741 -1.0960007
## 9      C                    a 5.966438 -0.4877708
## 10     A                    b 5.984307  1.6814375
## 11     B                    a 5.187291 -2.5821769
## 12     C                    b 5.272986  3.7159035
## 
## [[14]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 5.767436 -2.8132828
## 2      B                    b 3.912591 -3.3421894
## 3      C                    a 5.067504  1.9031159
## 4      A                    b 6.605141 -0.6935787
## 5      B                    a 6.232229 -4.1045826
## 6      C                    b 4.620886 -2.2647223
## 7      A                    a 3.650133 -3.3767899
## 8      B                    b 5.364918 -0.6580777
## 9      C                    a 4.636405 -0.4029239
## 10     A                    b 6.374653 -2.4540618
## 11     B                    a 5.291896  1.4170025
## 12     C                    b 5.710592 -2.6077684
## 
## [[15]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 3.667712  0.41575917
## 2      B                    b 5.070563  3.55071481
## 3      C                    a 5.464093 -6.33166522
## 4      A                    b 5.289158  0.78202833
## 5      B                    a 2.115059  2.83670048
## 6      C                    b 2.665308 -1.85988186
## 7      A                    a 3.269109 -0.02730222
## 8      B                    b 5.825010  1.56067627
## 9      C                    a 3.954960  5.41877612
## 10     A                    b 4.122807 -5.73755969
## 11     B                    a 4.599610  0.59784623
## 12     C                    b 3.731811  0.82945486
## 
## [[16]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.163724 -5.6188250
## 2      B                    b 7.029597  1.5743536
## 3      C                    a 5.429106 -1.5438820
## 4      A                    b 6.063948  3.6327977
## 5      B                    a 4.394177 -1.5383861
## 6      C                    b 6.074373  3.2718770
## 7      A                    a 4.287652  1.4755347
## 8      B                    b 4.821140 -0.7278869
## 9      C                    a 5.499760  6.3481417
## 10     A                    b 4.800429  3.5659187
## 11     B                    a 5.089895  2.6857836
## 12     C                    b 6.004910  2.6056219
## 
## [[17]]
##    group factor.letters.1.2..        x         y
## 1      A                    a 6.656178 -1.776417
## 2      B                    b 6.445636  1.513631
## 3      C                    a 5.744600 -4.568091
## 4      A                    b 4.309810 -1.076626
## 5      B                    a 4.208588 -1.410379
## 6      C                    b 4.737919  1.407967
## 7      A                    a 4.592083 -4.426020
## 8      B                    b 5.201311 -2.747864
## 9      C                    a 4.268053  1.373925
## 10     A                    b 5.729136 -2.137507
## 11     B                    a 5.326649 -1.135315
## 12     C                    b 2.292122  6.020583
## 
## [[18]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 4.449832 -0.2114727
## 2      B                    b 3.019214  5.4124253
## 3      C                    a 6.034598  1.3339114
## 4      A                    b 4.155160 -3.5728203
## 5      B                    a 3.983051  0.7446873
## 6      C                    b 5.674756 -0.3569345
## 7      A                    a 4.966773  2.0609669
## 8      B                    b 7.245491 -4.2233334
## 9      C                    a 4.545853  1.7259661
## 10     A                    b 5.194875  1.9131046
## 11     B                    a 5.031498 -2.8443711
## 12     C                    b 3.210669 -4.5465959
## 
## [[19]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 5.266538  2.18955436
## 2      B                    b 5.291532  1.04627662
## 3      C                    a 6.708922  4.08410241
## 4      A                    b 5.476702 -0.86598639
## 5      B                    a 6.307552  5.66521099
## 6      C                    b 6.806013 -0.05212731
## 7      A                    a 6.035386  1.62324874
## 8      B                    b 5.516518 -1.62012334
## 9      C                    a 4.605896 -0.24254819
## 10     A                    b 3.489760 -0.08890187
## 11     B                    a 5.005990 -0.43575145
## 12     C                    b 5.855007 -0.03258779
## 
## [[20]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 3.621281  1.8048552
## 2      B                    b 5.671536 -2.8522985
## 3      C                    a 3.845795  4.0810978
## 4      A                    b 5.422598 -0.7995708
## 5      B                    a 4.613010 -9.1048373
## 6      C                    b 3.759474 -0.7164597
## 7      A                    a 5.456962 -0.8165602
## 8      B                    b 3.589207  3.5711904
## 9      C                    a 6.933908  0.1535883
## 10     A                    b 5.569561  0.9931441
## 11     B                    a 5.932780  1.5948573
## 12     C                    b 3.454653  1.8420944
## 
## [[21]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 5.076716 -2.01273614
## 2      B                    b 4.739121 -2.40275071
## 3      C                    a 4.078130  4.83284010
## 4      A                    b 5.117606  0.05555500
## 5      B                    a 2.861590 -3.25019802
## 6      C                    b 4.680580  3.86834927
## 7      A                    a 4.259306 -0.43173821
## 8      B                    b 4.074209 -6.86402651
## 9      C                    a 5.757934 -0.25415046
## 10     A                    b 5.359560  0.59717948
## 11     B                    a 4.170764  3.68947749
## 12     C                    b 4.554248  0.01365759
## 
## [[22]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 3.705392  1.9455401
## 2      B                    b 4.602839 -1.3194909
## 3      C                    a 6.739482 -2.5992626
## 4      A                    b 6.023021  2.5959018
## 5      B                    a 4.472433 -1.5294456
## 6      C                    b 5.845996 -2.2763290
## 7      A                    a 5.821549 10.2056161
## 8      B                    b 3.664231 -1.3512480
## 9      C                    a 6.043118  5.1875944
## 10     A                    b 3.877009 -2.1554649
## 11     B                    a 5.690923  1.6008588
## 12     C                    b 5.368606 -0.2105608
## 
## [[23]]
##    group factor.letters.1.2..        x          y
## 1      A                    a 3.449436 -2.8126134
## 2      B                    b 5.273428  1.2614219
## 3      C                    a 6.885235 -1.6176067
## 4      A                    b 5.843199  2.6057816
## 5      B                    a 5.334534  3.4504726
## 6      C                    b 5.020385  0.0530880
## 7      A                    a 3.992708 -2.7835330
## 8      B                    b 5.412694 -1.5171958
## 9      C                    a 4.232968  3.6771995
## 10     A                    b 5.924992  3.6311332
## 11     B                    a 5.309149 -5.0948211
## 12     C                    b 6.966845  0.2840891
## 
## [[24]]
##    group factor.letters.1.2..        x         y
## 1      A                    a 5.762139  1.218843
## 2      B                    b 7.367204  1.527138
## 3      C                    a 4.956297  4.760013
## 4      A                    b 5.067098  3.138935
## 5      B                    a 5.155297 -3.143815
## 6      C                    b 4.467127 -2.371802
## 7      A                    a 3.171026  1.401895
## 8      B                    b 5.600555  1.661481
## 9      C                    a 5.085340 -2.042935
## 10     A                    b 4.603426 -8.384879
## 11     B                    a 3.382586 -3.253758
## 12     C                    b 4.977095 -1.971293
## 
## [[25]]
##    group factor.letters.1.2..        x           y
## 1      A                    a 4.030709  0.85457470
## 2      B                    b 5.412763  1.99365312
## 3      C                    a 4.084590 -0.99292436
## 4      A                    b 4.551684  4.47479440
## 5      B                    a 4.201498  0.51627063
## 6      C                    b 3.982712  0.57348085
## 7      A                    a 6.014989 -0.83884502
## 8      B                    b 4.348492  2.32505869
## 9      C                    a 5.038216 -1.00753587
## 10     A                    b 5.184079 -0.03158848
## 11     B                    a 5.451723 -0.41740501
## 12     C                    b 5.307880 -0.16039784