The Analysis Factor
Statistical Consulting, Resources, and Statistics Workshops for Researchers
by David Lillis, Ph.D.
In this lesson, we see how to use qplot to create a simple scatterplot.
The qplot (quick plot) system is a subset of the ggplot2 (grammar of graphics) package which you can use to create nice graphs. It is great for creating graphs of categorical data, because you can map symbol colour, size and shape to the levels of your categorical variable. To use qplot first install ggplot2 as follows:
[Read more…] about Doing Scatterplots in R
by David Lillis, Ph.D.
In Part 20 of this series, let’s see how to create mathematical expressions for your graph in R. We’ll use an example of graphing a cosine curve, along with relevant Greek letters as the axis label [Read more…] about Graphing Non-Linear Mathematical Expressions in R
by David Lillis, Ph.D.
Today we see how to set up multiple graphs on the same page. We use the syntax par(mfrow=(A,B)) [Read more…] about R Graphics: Multiple Graphs and par(mfrow=(A,B))
by David Lillis, Ph.D.
In Part 7, let’s look at further plotting in R. Try entering the following three commands together (the semi-colon allows you to place several commands on the same line).
Let’s take an example with two variables and enhance it.
X <- c(3, 4, 6, 6, 7, 8, 9, 12)
B1 <- c(4, 5, 6, 7, 17, 18, 19, 22)
B2 <- c(3, 5, 8, 10, 19, 21, 22, 26)
[Read more…] about R Is Not So Hard! A Tutorial, Part 7: More Plotting in R
by David Lillis, Ph.D.
In Part 6, let’s look at basic plotting in R. Try entering the following three commands together (the semi-colon allows you to place several commands on the same line).
x <- seq(-4, 4, 0.2) ; y <- 2*x^2 + 4*x - 7
plot(x, y) [Read more…] about R Is Not So Hard! A Tutorial, Part 6: Basic Plotting in R