[read note] How to Read a Paper

原文：How to Read a Paper.pdf

reasons

1. review paper for a conference or a class
2. keep current in the field
3. for a literature survey of a new field

three-pass approach

1. general idea about the paper
2. grasp the paper's content, not details
3. understand the paper in depth

the first pass (5-10 min)

quick scan, get a bird's-eye view of the paper. ... decide whether need more passes.

1. Carefully read the title, abstract, and introduction
2. Read the section and sub-section headings, but ignore everything else
3. Read the conclusions
4. Glance over the references, mentally ticking off the one's you've already read

answer 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?

the second pass (60 min)

read the paper with greater care, but ignore details such as proofs. ... jot down the key points, or make comments in the margins.

1. Look carefully at the figures, diagrams and other illustrations in the paper. Pay special attention to graphs. Are the axes properly labeled? Are results shown with error bars, so that conclusion are statistically significant? 
2. Remember to mark relevant unread references for further reading (a good way to learn more about the background of the paper)

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.

Sometimes you won't understand a paper even at the end of the second pass. This may be because the subject matter is new to you, with unfamiliar terminology and acronyms. Or the authors may use a proof or experimental technique that you don't understand, so that the bulk of the paper is incomprehensible. The paper may be poorly written with unsubstantiated assertions and numerous forward references. Or it could just be that it's late a night and you're tired. You can choose to:

• set the paper aside, hoping you don't need to understand the material to be successful in your career
• return to the paper later, perhaps after reading background material
• persevere and go on to the third pass

the third pass (240-300 min for beginners and 60 min for an experienced reader)

fully understand a paper... 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-creation with the actual paper, you can easily identify not only a paper's innovations, but also 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 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.

Doing a literature survey

1. use an academic search engine and some well-chosen keywords to find three to five recent papers in the area. Do one pass on each paper to get a sense of the work, then read their related work sections. You will find a thumbnail summary of the recent work, and perhaps, if you can find such an survey, you are done. Read the survey... good luck.
2. find shared citations and repeated author names in the bibliography. these are the key papers and researchers in that area. Download the key papers and set them aside. Then go to the websites of the key researchers and see what they've published recently. That will help you identify the top conferences in that field because the best researchers usually publish in the top conferences.
3. go to the website for these top conferences and look through their recent proceedings. A quick scan will usually identify recent high-quality related work. These papers, along with the ones you set aside earlier, constitute the first version of your survey. Make two passes through there papers. If they all cite a key paper that you didn't not find earlier, obtain and read it, iterating as necessary.

Related Work

• Timothy Roscoe's paper on Writing reviews for systems conferences
• Henning Schulzrinne's comprehensive website
• George Whitesides's overview of the process
• Simon Peyton Jones's website covers the entire spectrum of research