How to Read a Paper

1. First pass #

• The first pass is a quick scan to get a bird’s-eye view of the paper. You can also decide whether you need to do anymore passes. This pass should take about five to ten minutes and consists of the following steps:
  1. Carefully read the title, abstract, and introduction
  2. Read the section and sub-section headings, but ignore everything else
  3. Glance at the mathematical content (if any) to deter-mine the underlying theoretical foundations
  4. Read the conclusions
  5. Glance over the references, mentally ticking off the ones you’ve already read
• At the end of the first pass, you should be able to answer the five Cs:
  1. Category: What type of paper is this? A measurement paper? An analysis of an existing system? A description of a research prototype?
  2. Context: Which other papers is it related to? Which theoretical bases were used to analyze the problem?
  3. Correctness: Do the assumptions appear to be valid?
  4. Contributions: What are the paper’s main contributions?
  5. Clarity: Is the paper well written?

2. Second pass #

• In the second pass, read the paper with greater care, but ignore details such as proofs. It helps to jot down the key points, or to make comments in the margins, as you read.
  1. Look carefully at the figures, diagrams and other illustrations in the paper. Pay special attention to graphs.Are the axes properly labelled? Are results shown with error bars, so that conclusions are statistically significant? Common mistakes like these will separate rushed, shoddy work from the truly excellent.
  2. Remember to mark relevant unread references for further reading (this is a good way to learn more about the background of the paper).
• The second pass should take up to an hour for an experienced reader. After this pass, you should be able to grasp the content of the paper. You should be able to summarize the main thrust of the paper, with supporting evidence, to someone else. This level of detail is appropriate for a paper in which you are interested, but does not lie in your research specialty.

3. Third pass #

• To fully understand a paper, particularly if you are a re-viewer, requires a third pass. The key to the third pass is to attempt to virtually re-implement the paper: that is,making the same assumptions as the authors, re-create the work. By comparing this re-creation with the actual paper,you can easily identify not only a paper’s innovations, but also its hidden failings and assumptions.
• This pass requires great attention to detail. You should identify and challenge every assumption in every statement. Moreover, you should think about how you yourself would present a particular idea. This comparison of the actual with the virtual lends a sharp insight into the proof and presentation techniques in the paper and you can very likely add this to your repertoire of tools. During this pass, you should also jot down ideas for future work.
• At the end of this pass, you should be able to reconstruct the entire structure of the paper from memory, as well as be able to identify its strong and weak points. In particular, you should be able to pinpoint implicit assumptions, missing citations to relevant work, and potential issues with experimental or analytical techniques.