Heatmaps are a common way to visualize matrices and R provides a variety of methods to generate these diagrams. One of the key features of a heatmap is the color scheme employed. By default the image method uses heat.colors which ranges from red (lowest values) to white (highest values). Other palettes include rainbow and topographical. […]
Correlating Continuous and Categorical Variables
At work, a colleague gave an interesting presentation on characterizing associations between continuous and categorical variables. I expect that I will be facing this issue in some upcoming work so was doing a little reading and made some notes for myself. Given a continuous variable Y and a categorical variable G, is the distribution of […]
Viewing Pathways
There are a variety of pathway databases such as KEGG, Reactome and Wikipathways. One of my projects involves pathway analysis, and it’d be nice to easily display them. In many cases, one can simply display a pre-generated image of the pathway (such as in KEGG), but in general, interactivity is nice. However, the latter would […]
Plate Well Series Plots in R
Plate well series plots are a common way to summarize well level data across multiple plates in a high throughput screen. An example can be seen in Zhang et al. As I’ve been working with RNAi screens, this visualization has been a useful way to summarize screening data and the various transformations on that data. […]
From Theory to Practice
Some time back, John Van Drie and myself had done some work on characterizing structure-activity cliffs, which are molecules that have very similar structures but very different activities. The term originated from Maggiora, who suggested that this was a reason for the failure of many QSAR models. At the same time, such cliffs can represent […]