An R Introduction to Statistics

matrix

Significance Test for Kendall's Tau-b

  A variation of the standard definition of Kendall correlation coefficient is necessary in order to deal with data samples with tied ranks. It known as the Kendall’s tau-b coefficient and is more effective in determining whether two non-parametric data samples with ties are correlated.

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.

Kendall Rank Coefficient

  The correlation coefficient is a measurement of correlation between two random variables. While its computation is straightforward, it is not readily applicable to non-parametric statistics.

Matrix Construction

A discussion on various ways to construct a matrix in R.

Matrix

fractal-09hA matrix is a collection of data elements arranged in a two-dimensional rectangular layout. The following is an example of a matrix with 2 rows and 3 columns.

    [         ]
      2  4  3
A =   1  5  7