[PEINTO-GEN]

Visualize

Introduction

Datasets often look like this—a huge bunch of numbers arranged in a matrix. Doesn’t seem to be saying anything understandable, right? This is where data visualization comes in.

One commonly used data visualization tool (particularly in gene expression analysis) is the heat map. A heat map assigns different colors to different values in a matrix. As seen above, we can choose to represent positive and negative values with shades of red and turquoise, respectively. The farther from zero a value is, the brighter the color that represents it.

Without the numbers, it becomes easy to pinpoint extreme values and compare rows or columns. This aids researchers in interpreting the data, enabling them to make hypotheses and helping them decide what to do next. Data visualization can be used as a preliminary step to know what other computations must be done with the data; or a way to summarize the results of computations already done.

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A Gentle Reminder

In exploring the following visualizations, we would like you to focus on how they are able to summarize data (paint the big picture), not on the identities and actual biological functions of the individual genes.

In your exploration, you will see information like this:

You are free, of course, to try and understand what each gene is for, but we aren’t putting pressure on you to do so.

Visualization Methods

Heat Maps Intro

Heat Maps

Crawl Network Intro

Crawl Network