Google Maps and ggmap

December 22nd, 2013

The ggmap package can be used to access maps from the Google Maps API and there are a number of examples on various statistics related blogs. These include here, here and here. Read the rest of this entry »

Seasonal Trend Decomposition in R

January 11th, 2013

The Seasonal Trend Decomposition using Loess (STL) is an algorithm that was developed to help to divide up a time series into three components namely: the trend, seasonality and remainder. The methodology was presented by Robert Cleveland, William Cleveland, Jean McRae and Irma Terpenning in the Journal of Official Statistics in 1990. The STL is available within R via the stl function. Read the rest of this entry »

Graph Types: Pie Charts

October 13th, 2012

The pie chart is a frequently seen graph that uses area to compare percentages for a set of categories. Although this type of graph is based on comparing single metric for each category the display is two dimensional but sometimes even appears in three dimensions. Read the rest of this entry »

Graph Design Principles

June 25th, 2012

There are a set of basic principles that hold true for the design of many graphs and various authors have their own preferences. One author who is prominent due to his good work in the area of data visualisation and presentation of evidence to support decision making is Edward Tufte. Read the rest of this entry »

Statistics Books