R video tutorial number 2

READ TEXT FILES, RUN MODELS

The Decision Science News R video tutorials continue with number 2. (If you missed that last one, you will want to watch R Video Tutorial Number 1 first.) The Goldstein pedometer dataset can be downloaded from http://www.dangoldstein.com/flash/Rtutorial2/pedometer.csv

Topics covered this week include:

• Tricking R into starting in your working directory
• Reading in text files
• Accessing columns in data frames
• Creating histograms
• Side effects and optional parameters of function calls
• Fitting simple linear models
• Adding least-squares and loess lines to plots

The commands in the tutorial are:

myData=read.table("pedometer.csv", header=TRUE, sep=",")
x=hist(myData$Steps,col="lightblue")
x=hist(myData$Steps,breaks=20,col="lightblue")
plot(myData$Steps ~ myData$Observation,col="blue")
myModel=lm(myData$Steps ~ myData$Observation)
summary(myModel)
lines(fitted(myModel))
lines(fitted(loess(myModel)),col="red")


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Tags: Encyclopedia, R, statistics