Visualizing Presidential Speeches with Tag Clouds

I’ve written about word clouds before, but many more options for visualizing information have become available since my first post about Wordle.  Some newer applications include Tagxedo, Tagul, WordSift, TagCrowd, each of which has slightly different features and ways to customize the look of your tag cloud.

Why are these applications so popular?  A lot can be gleaned from looking at a text in this format.  There are many more complex ways to analyze a text (one of my favorites is Xiaofei Lu’s Synlex, which can analyze a wide range of features from the frequency of structures to the complexity of the text) but word clouds are simple and straightforward.

A great example is the US Presidential Speeches Tag Cloud page by Chirag Mehta.  It’s based on Tagline, the Timeline-based Tag Cloud Generator that he developed.  This is actually a series of tag clouds with a slider bar that allows the viewer to scroll though 200 years of presidential speeches.  It’s interesting to see how the most frequent words and themes change over time, something that is very easy to see as you scroll through the tag clouds.

How can students use these tools?  The more complex tools, which allow students to target specific features, might be the best option for analyzing one’s own writing.  On the other hand, tag clouds would be a better option if a student just needs a snapshot of a text.  For example, by feeding a reading assignment into a tag cloud generator, it would be very easy to pick out the most frequent terms and themes prior to reading it — a little like having the text skimmed for you.

Do you use tag clouds and other text analyzers with your students?  Leave a comment to share your tips and ideas.

Show Me The Money

I’ve posted about finding royalty- and copyright-free images on line before.  In this post, I’d like to share an often overlooked source: the U.S. Government.  Many government departments have images in the public domain, which usually means that teachers can use them in presentations, classroom activities, and almost any not-for-profit ways you can imagine.  Of course, there are exceptions, so be sure to read the fine print.

The U.S. Mint

The Mint publishes some very nice images of the money it produces including coins commemorating states, presidents, first ladies, national parks, and significant historical events.  Most are available for free download, though a few are copyrighted (such as the Sacagawea dollar coin).  There are also a few anti-counterfeiting restrictions on reproducing paper money, so be sure to read the fine print on the website.

NASA

The National Aeronautics and Space Administration has some amazing copyright-free images and videos available.  Whether you are looking for images of astronauts, rockets or other spacecraft, or images of outerspace, the NASA website has you covered.  Some of the images include those from the Hubble Telescope which has captured extraterrestrial images for over a decade.  There are lots of science- and engineering-related images, and the website makes it easy to search for them.

CDC

You might not ordinarily think to look on the website for the Center for Disease Control and Prevention, but but the Public Health Image Library has lots of interesting stock images available, related to topics such as home safety, personal hygiene, agriculture, child safety and more.  Of course, you’ll also find lots of images of bacteria, microscopic pests, and other diseases, some of which may not be suitable for children.

More

For links to photos from more U.S. Government photos and images, visit the USA.gov website.  You will find links to images from lots of other departments related to agriculture, the environment, defense, safety, science and technology and others.  In essence, these images are “free” because you’ve paid for them with your taxes.  So, don’t hesitate to take a look and use them if you need to.