An R Introduction to Statistics


Hierarchical Cluster Analysis

  With the distance matrix found in previous tutorial, we can use various techniques of cluster analysis for relationship discovery. For example, in the data set mtcars, we can run the distance matrix with hclust, and plot a dendrogram that displays a hierarchical relationship among the vehicles.

Significance Test for Logistic Regression

A tutorial on performing the significance test for a logistic regression.

Distance Matrix by GPU

A comparison of computing the distance matrix in CPU with dist function in core R, and in GPU with rpuDist in rpud.

Logistic Regression

fractal-12h We use the logistic regression equation to predict the probability of a dependent variable taking the dichotomy values 0 or 1. Suppose x1, x2, ..., xp are the independent variables, α and βk (k = 1, 2, ..., p) are the parameters, and E(y) is the expected value of the dependent variable y, then the logistic regression equation is:

E (y) = 1∕(1 +e- (α+  kβkxk))

Mann-Whitney-Wilcoxon Test

A tutorial of performing statistical analysis with the Mann-Whitney-Wilcoxon test.

Population Mean Between Two Independent Samples

A tutorial on statistical inference about population mean between two independent samples.

Data Frame Row Slice

A tutorial on retrieving a collection of row vectors in a data frame. Discussion on the usage of numeric, name and logical indexing.

Data Frame Column Slice

A tutorial on retrieving a collection of column vectors in a data frame with the single square operator. Discussion on usage of numeric and name indexing.

Data Frame Column Vector

A tutorial on retrieving individual column vectors in a data frame with the double square operator.