Writing your first paper: Step Eight: Discussion
This post is part of a series (that is taking a long time to write) on writing your first research paper. I plan to use this information for my graduate students. So feel free to send your thoughts, comments, and hysterical rejoinders. Also, all data is completely made-up so don't quote me on anything.
The discussion section is intended to explain the significance of your data, discrepancies and limitations of experimental design, the theory/meaning of the cumulative result, and its broader impact. So for the ice cream example paper the first part of the discussion would discuss case by case data analysis.
Liquid nitrogen ice cream displayed superior texture to hand crank and electric machine-made ice cream, but equal texture to store bought as determined by viscosity testing. Additionally, liquid nitrogen ice cream was preferred to hand crank and electric machine ice cream in taste tests. Thus, liquid nitrogen can produce ice cream with superior texture and taste, comparable to store-bought, when manufactured in the home.
This part of the paragraph summarizes the data presented in results and ties it together with our message: LN2 is a viable home alternative for creating ice cream. Next, we will discuss the limitations of our data, experimental design, and hypothesis.
However, because the test group consisted of a narrow age range, additional testing may be required to determine the appeal of LN2 ice cream in a broader population size. Additionally, our sample size was not sufficient to differentiate preferences between LN2 ice cream and the store-bought positive control. While we found that LN2 ice cream was preferred to other home techniques, it is unclear how this preference will affect consumers in the market for home ice cream makers. LN2 ice cream can be made very quickly and displays superior texture to other home methods. However, some users expressed concerns as to the safety of an LN2 system. Although we demonstrated that our self-contained system can be used safely by the average consumer, this negative perception would most likely have to be addressed in the marketing campaign. Additionally, it is not clear whether the superiority of LN2 home ice cream machines would translate into an increase in the size of the consumer market or simply an increase in the market share. Ice cream consumers will most likely continue to rely on store purchase as the primary method of obtaining ice cream products.
So in this section we talk about experimental difficulties. i.e., we tested only college kids, small sample size, no market research. We also talk about potential problems with our hypothesis, i.e., consumer safety concerns, and suggest how these could be addressed (marketing campaign). It is important here to air all your dirty laundry. If you can criticize yourself effectively and suggest possible alternative explanations, experiments, etc to address your deficiencies you will leave very little for a reviewer to pick apart, and they will be impressed with your 'tight' paper.
Finally, the impact of the theory and its broader implications are discussed.
Home ice cream machines represent a large market in the US. However, when polled the majority of users say that use is limited by poor texture and long freezing times. We have designed a home ice cream system using liquid nitrogen as the freezing medium. This system can be operated safely by the average user, and produces ice cream in seconds with texture and taste equivalent to that of store bought varieties. The LN2 machine represents a significant advance in home ice cream making, with the potential to address most consumer concerns. Although additional testing is needed to confirm, it's introduction to the marketplace could substantially increase the number of home ice cream machine users, or at least the frequency of machine use with existing consumers.
This last paragraph is the most important and is your final chance to impress the reader with what you have done. Use the paragraph wisely. This is why I like to put limitations in previous paragraphs, so the last one can discuss the positive impact of your work as much as possible.
Well, more later, I think all we have left are references!!!