# correlation matrix

### Correlation scatter-plot matrix for ordered-categorical data

April 7, 2010 |

When analyzing a questionnaire, one often wants to view the correlation between two or more Likert questionnaire item’s (for example: two ordered categorical vectors ranging from 1 to 5). When dealing with several such Likert variable’s, a clear presentation of all the pairwise relation’s between our variable can be ... [Read more...]

### Comparison of different circle graphs

March 24, 2009 |

See in my Picasa here and get corrplot package here. Thanks Bob O'Hara's advice:)I found people's tastes differ, so input parameter col (fill color) and bg (background color) was added in new edition. What is more, now you can order your variables usin... [Read more...]

### Visulization of correlation matrix

March 12, 2009 |

Color Imagedata(mtcars)fit = lm(mpg ~ ., mtcars)cor = summary(fit, correlation = TRUE)\$correlationcor2 = t(cor[11:1, ])colors = c("#A50F15", "#DE2D26", "#FB6A4A", "#FCAE91", "#FEE5D9","white", "#EFF3FF", "#BDD7E7", "#6BAED6", "#3182BD", "#08519C")image(1:11, 1:11, cor2, axes = FALSE, ann = F, col = colors)text(rep(1:11, 11), rep(1:11, each = 11), round(100 * cor2))Ellipseslibrary(... [Read more...]