Saturday, December 24, 2016

Writing a good related work section

I assigned the following as a writing assignment in my graduate course, "Applications of Fading Channels".  We had read about 30 papers in the research area of RF sensing, and I asked them to write a related work section that would then go in their final report. I wanted to give them specific instructions about how to write a good section, and to give them very quantitative instructions on how I would grade their submission.  I think it helped some of them write very good related work sections, that I would have no complaints about if they had appeared in a submission to a good conference or journal.
Here's what I told them.
Write a related work section describing the area of RF sensing.  I want you to focus on following these two tips.
  1. Tell a story.  Your story is about the state-of-the-art in the area, and cite papers to back up your story.  The papers themselves are not the story.  Don't cite the papers just so that you can cite them all.  One example of this: DO NOT start a sentence with a reference -- good citations are normally at the end of a sentence rather than at the start. For example, compare these two: (a) "Objects moving near a transmitter or receiver cause fading [6]", or (b) "Reference [6] shows that objects moving near a transmitter or receiver cause fading". Using (b) makes the subject "Reference [6]", which makes the reader believe that the paper [6] is doing the action, not "objects moving near a transmitter".  Using form (b) makes it seem like you just want to check off of a reference that you need to cite.  Using (a) tells part of a story about what object motion does to the channel, which then primes the reader to think about detecting it using fading measurements.  I expect that your paper will not have the papers you're referring to as the subject of a sentence.
  2. Divide or subdivide the area of research.  For each subcategory, describe generally this category of research, giving detail about one or two example papers in this area.  Your final sentence (or two) would then describe why your research is similar or dissimilar to this subcategory, or what the limitations / drawbacks of this category are.  To make up a formula for these paragraphs:
    1. Divide or subdivide the area of research:  Example: "Device-free localization may be subdivided into two categories of algorithms: model-based or fingerprint-based."  In some way, you are categorizing.
    2. For each subcategory, describe generally this category of research, giving detail about one or two example papers in this area.  Example:  "Model-based methods assume that the change in channel on any link can be described by a statistical and/or spatial model as a function of the link's endpoints and other measurable channel characteristics [1,2,3,4,5].  For example, [1] assumes that RSS will be attenuated when a person stands in an ellipse with foci at the transmitter and receiver coordinates.  Fingerprint-based methods measure a database of channel changes as a function of person position during a calibration period, and later match measured channel changes to the database."
    3. Your research in comparison or limitations / drawbacks: For example, in the above, if my project was on a new method that did neither, I would say "This paper explores a third category which neither requires a calibration database nor makes model assumptions.".  If I just wanted to explain the drawbacks, I would say, "The model-based methods are inaccurate because of any mismatch between the model and reality; the fingerprint-based methods require significant time to record the calibration database."
I will quantitatively judge how well you are following these two guidelines:
  1. Count how many references are used as the subject of a sentence.  Try to eliminate these. 
  2. Count how many divisions and subdivisions are used.  Try to maximize this number.

I'm interested in comments or suggestions.  I've always had a hard time providing specific mentoring for research writing, my typical approach is "I know it when I see it".  I'm hoping this is one step in being specific.