Question

R Programming Exercise Book

Problem 57 (Difficulty: Easy)

A normal distribution has a standard deviation of 35 and mean of 15. From this generate 2 to 400 samples. After generating the samples utilize the plot command to plot the mean of the generated sample (x-axis) against the number of samples. Create a second plot of the density of the 400 samples that you generated.

This code can be solved in 4 to 8 lines.

For this problem use the following variables:

For the mean use: Mean_of_graph

For Standard Deviation use: Standard_deviation_of_data

Answer 1

> særnorm(400,15,35);s (1) 17.21392109-13.96711623 30.18211245 41.68563806 -35.25119099 (6) 46.07753 777 20.70320792 18.23545940 9.67142287 46.64203465 (391) 10.73692908 10.43572317 19.74686318 15.14383322 47.45652896 (396) -1.11665383 -25.51857890 -30.87765958 13.78505844 -20.34106965 > Mean_of_graph=mean(s); Mean_of graph (1) 14.268 > Standard_deviation_of_data=sqrt((399/400)*var(s));Standard deviation_of_data (1) 32.65197 >x=seq(Mean_of_graph-4*Standard deviation_of_data, Mean_of_graph+4* Standard_deviation_of_data,0.1) > pr=dnorm(x, Mean_of graph, Standard_deviation_of_data) > plot(x,pr,"") 0.012 0.010 0.008 jd 0.006 0.004 0.002 0.000 -100 50 100 150

>x=seq(15-4*35,15+4*35,0.1) > pr=dnorm(x,15,35) > plot(x,pr,"l") 0.010 0.008 0.006 pr 0.004 0.002 0.000 -100 -50 100 150