How to write a strong introduction into a research paper?
How does one write a strong (good) introduction into a research paper? Some introductions make me really curious about the rest of the paper while others do not. Although it is relatively easy to say which introductions are good and which are not, I find it difficult to distill what makes the difference. There is a previous question about writing introductions (How to write a Ph.D. thesis Introduction chapter?) but it is about Ph.D theses.
write the paper first, then tack on a beginning and end. that way you will know what its about.
Here's a bit of meta-advice on this point. One major way I've learned how to improve introductions is by thinking hard about negative referee reports. In my experience, when a paper gets a referee report that I disagree with, the explanation is often that the introduction needed to be clearer about something.
@Noah's advice is spot on (although one might aspire to write a good introduction earlier in the day than this) and really points to the importance of the question: the difference between an average introduction and a good one is often the difference between your paper being grokked or not by some fairly random referee who has sufficient subject-level expertise but is not closely clued in to your particular perspective.
This is very area specific. I'll start with the caveat that I write papers in computer science, so YMMV.
The way I think about introductions (which is not to say they are GOOD introductions) is that they tell the story of the paper in brief. Every paper has a story to tell, starting with
- Here's a fascinating question
- Here's what people have tried to do (in brief: not a full related work section, but a high level assesment)
- here's the key challenge preventing further progress
- Voila: here's our complete/partial/intermediate/awesome solution
- (additionally) and here's how it works.
The intro is typically the "hook" to read the rest of the paper, so you have to provide a birds-eye view that draws the reader in without drowning them in details.
The thing that separates a good intro from a bad one is knowing where that right level of detail is, so you're not either totally vacuous or mired in details. Getting this right is an art and depends on your field, your results, the problem, and your understanding of the target audience.
A few pure theory papers begin with "Let X be a..." instead of "Hey look at this shiny rock I found."
I was recently forwarded (what I think) is a guide full of excellent advice, Writing Tips for Ph. D. Students by John Cochrane. In it, Cochrane has a brief section of advice on the introduction:
The introduction should start with what you do in this paper, the major contribution. You must explain that contribution so that people can understand it. Don’t just state your conclusion: “My results show that the pecking-order theory is rejected.” Give the fact behind that result. “In a regression of x on y, controlling for z, the coeﬃcient is q.”
The ﬁrst sentence is the hardest. Do not start with philosophy, “Financial economists have long wondered if markets are eﬃcient.” Do not start with “The ﬁnance literature has long been interested in x.” Your paper must be interesting on its own, and not just because lots of other people wasted space on the subject. Do not start with a long motivation of how important the issue is to public policy. All of this is known to writers as “clearing your throat.” It’s a waste of space. Start with your central contribution.
Three pages is a good upper limit for the introduction.
This just reiterates the point both Oldboy and Suresh made that the introduction should clearly state what the paper is about, and also some more detailed advice about avoiding generic intro. statements. (Note the upper bound is good for social science articles that may be from 20~40 pages, it should be much lower for briefer articles in different fields or journals.)
Yes, I read something somewhere before about these types of generic introductory phrases, calling the practice "grandfathering" ... which is the idea of writing passages out of a sense of tradition in such a way that they are extremely familiar only to experts and incomprehensible to anyone else. Hence these passages are utterly useless since nobody learns anything. It seems introductions to papers are littered with them. I do it myself I guess. Bad habits. :)
After I read this advice @badroit I went through my current papers and edited such things out. When I first write something I don't care very much about specific sentences, and if writing such things helps get the ball rolling then that is fine - but they should be deleted or copy-edited later on.
I've seen suggestions to use such statements as hyperbole to establish interest in the work in the introduction. E.g. if I wrote a paper about police stops in New York City I may allude to the Diallo shooting in the intro. This is IMO bad practice though, as they tend to be such aloof references to the current work they are basically meaningless. This post discusses similar behavior in citing generic original work, Sociology citing Becker.
Some points to take into consideration (not an exhaustive list):
- Correct grammar: for obvious reasons.
- Proper literature review: many readers find annoying when the authors claim to be the first people attacking the problem of interest, while the reader is well aware of other relevant references.
- State clearly the aims and main results in the introduction. It is frustrating when you have to read the entire paper to understand its purpose.
- Not too long, not too short. A long introduction will make the idea of skipping this section really tempting, while a short introduction might compromise clarity or points 2 and 3.
- Cover points of interest for different audiences. For example, try to explain the impact of the paper or the topic in terms of both theoretical and practical issues.
- Make a concrete analogy. A concrete analogy will intertwine to the text and allow room for the readers to project their background into it.
- Make the ideas constantly contradict each other. "Contradiction" here doesn't mean as a logical contradiction, but more about "a surprising, but still logical step of development". It introduces why the topic is important, and is the source of excitation, enlightenment, and satisfaction. Being able to solve contradictions is the reason why the ideas survive and are worth the attention.
- Notice where the flow emerges and dissipates. This will help overcome the jargon barrier without having to oversimplify them. Imagine the article is like a heatmap, and each jargon/theorem/proof is a heat source, then the writer's job is to locate them not too hot (too dense) or too cold (too uninformative). The introduction is also the same.
I have an article for this, you can check it out: Making concrete analogies and big pictures.
Start writing the body paragraphs then use the basic ideas of all of them and then create an introduction and concluding paragraphs!