Logistic Regression: Model Building and Interpretation

Logistic regression is a widely used modelling approach, however little is known about the modelling processes and interpretation of model outputs. This post demonstrates how to build a logistic model with R and how to interpret the results.

Zoom Your Plots with ggforce

You can use facet_zoom from the ggforce package to zoom out graphs instead of using your mouse (Contextual zoom).

Formatting axis labels in ggplot

With the ggplot2 package, you've got full control over the axes labels in charts. Here we are going to look at some of the most commonly needed formatting options in order to make your graph aesthetically pleasing

Weighted LOESS (LOcal regrESSion)

LOcal regrESSion (LOESS) or LOcally WEighted Scatter-plot Smoother (LOWESS) LOESS or LOWESS is a nonparametric technique to fit a smooth curve through points in a scatter plot. This approach uses locally estimated linear regression at its core. The following code illustrates how to include a loess line using the ggplot2 package. library(ggplot2) set.seed(1) x <- rnorm(60) y <- c(rnorm(40), 10, rnorm(19)) df <- data.frame(x=x, y=y) ## Without weights ggplot(data=df, aes(x=x, y=y)) + geom_point() + geom_smooth(method=loess, legend=FALSE) Furthermore your can plot loess smoothing weighting the observations as follows:

Highlight data points in a scatterplot

Highlight selected points in the scatterplot

Customizing boxplots with ggplot2

Boxplot is probably one of the most common type of graphics. This will show how to customize boxplots.