Tips on Literature Surveys
CMSC 601 -- Spring 2009
Prof. Marie desJardins

Finding Relevant Papers

• Google is a useful tool, but should not be the only place you look! Also, as you get to know the field you're investigating, you can keep going back to google (and other sources) with new keywords (buzzwords) you've discovered.
• CiteSeer, an online citation index and paper database originally developed by NEC, is a terrific resource. Many of the top google hits will likely be to CiteSeer papers. In CiteSeer, you can search by keyword/title/author, and can follow citation links forward and backward from important papers. There are also other nifty features like semantically similar papers, and "importance" measured based on number of citations. Many papers have associated (but possibly incomplete/incorrect) BibTeX entries.
• For AI papers, if you really don't know where to start, AI Topics is sometimes helpful. It's a AAAI-maintained website that has some introductory material, a collection of links on various topics, news articles, and other interesting pointers. But the actual content is on the non-technical side (it's more at the high-school term-paper level), so it should just be one resource, not your primary one.
• Identify a few important and relevant (recent or classic/seminal) papers, and work forwards and backwards through citation links (following references in the paper, and looking in CiteSeer to see who later cited this paper).
• It's important to know what are the key publications (top journals and conferences) and researchers (most published and cited authors) in your field of interest. You may be able to find this out early in the process by asking somebody who's knowledgeable, or by stumbling on (or starting from) the key seminal paper(s). Or you may have to discover it more gradually. (If you see a citation or a name repeatedly, look it up! It's important! But also note: "important" is not synonymous with "good" -- sometimes everybody cites a paper just because everybody else does, not because it's actually a particularly good or useful paper.)
• Also pay attention to institutions -- you'll quickly learn which places are doing important work in your area. (And my list of top institutions for AI won't be the same as your list of top institutions for graphics, or whatever. In fact, my list of top institutions for my particular subareas of AI might not be the same as that of some other AI researcher with a different focus. Of course, these things are subjective, so my list might not even be the same as that of a researcher with the same focus...)

Locating and Reading Papers

• If you can't find a paper online, try the library, other students, your advisor or outside reader. (For example, I have most volumes of the Machine Learning Journal in my office. Also, as a AAAI member, I have online access to all AAAI publications.)
• Be sure you use your time wisely, using the paper-reading tips we've already gone over to figure out which papers are worth reading closely, and which only deserve a cursory review.
• Don't make the mistake of "depth-first search" of the paper space. Instead, look at papers closely enough to know how important they are, and to start creating clusters of "similar" papers (i.e., identifying themes, threads, or styles of research within the field). Then organize your reading by clusters. This is a much more efficient way to read than a scattershot approach. Also, doing this as you go along will help you to organize the literature survey itself.
• As you read papers, make note of important citations to follow up on (and what cluster those citations seem to belong to).
• Know when to stop. There will be more related fields than you can possibly follow up on. Be prepared to say "Researchers in statistics and physics also touch on these topics," perhaps (if you're lucky) with a pointer to relevant survey papers on those areas, and leave it at that.
• Take notes and keep them in an organized system -- notebook, online, whatever. Don't just scribble on pieces of paper. I like to make notes in the margins of papers, but also to write short bulleted summaries of papers that are particularly relevant for an area that I'm trying to synthesize.