CPR for Bad Scientific Writing

When your advisor or a peer reviewer writes on your paper comments such as, “unclear” or “ambiguous” or “obtuse”, do you think that s/he:

a)    is just picking on you
b)    doesn’t understand your unique “style”
c)    is making a subjective judgment
d)    might be right

If you picked d, you have taken the first step toward becoming a good writer. 

It’s true that some professors are a bit obsessed with grammar and punctuation, but the real obstacle to good scientific writing is poor style.  In fact, a paragraph with proper punctuation and grammar might be utterly incomprehensible, whereas one that has not followed grammatical rules is perfectly clear in its message.  Consider the following grammatically correct sentence:

Increasing foreign competition and technological change, in a variety of forms, are now, as they always have been, disrupting various well-established patterns in terms of industrial organization.

Difficult to understand, right?  That’s because the style is poor. 

Next, consider an ungrammatical, but quite understandable sentence:

The material applied to the blades of wind turbines age rapidly in tests.

It should be obvious that the first example would be much more difficult for an editor to fix than the second example.  I’m not saying that you should neglect grammar and punctuation.  My point is that style is crucial.

What you should strive for, above all else, is clarity in your writing style.  Clarity is an aspect of style that is particularly relevant to scientific writing, but is one of the most difficult for some scientists to achieve. So how do you develop clarity and other stylistic goals? 

If you are having extreme difficulty, there are a few things you can do immediately.  By attending to three aspects of writing: concision, precision, and revision (CPR), you can quickly improve your technical writing.

Concision

Begin by eliminating all unnecessary or meaningless words:  “it is noted”, “as we have seen”, “in terms of”.  By dropping extraneous words, we not only reduce the wordiness, but can better see what other revisions are necessary.

Precision

Precision can be improved by selecting those phrases that are not exact in their meaning and rewriting them.  Pay particular attention to those noun clusters that scientists are so fond of: “nutrient use efficiency respiratory rates” or “plant trait plasticity variation” The best way to improve a paragraph’s meaning is to choose clear, meaningful nouns and follow them with verbs that explain the noun’s meaning in the sentence: “Plasticity of plant traits varies among species.”

Revision

After cleansing our writing of excess verbiage and improving the meaning of the remaining words, we can now revise and improve the style of the writing.  The preceding posts provide guidance as to how to make transitions from one sentence to the next and to meet reader expectations in sentence structure.  However, some very simple approaches such as using connecting words (this, also, as well as, recently) will go a long way toward improving the reader’s understanding.

To take the next steps in improving your technical writing skills, you must delve into writing guides, particularly ones that focus on style and clarity.  The best known of these is The Elements of Style by Strunk and White.  There are many others readily found on the internet.

More Principles of Scientific Writing

In the last post, we covered the first principle of scientific writing dealing with subject-verb separation.  We are using an example of scientific writing (an abstract) selected randomly from the literature to examine principles of writing proposed by Gopen and Swan (1990).  In this post, we'll consider the "stress position" and the "topic position" and how to use these concepts to improve our writing.

The Stress Position

Readers expect to see the point of a sentence appear in what is known as the "stress position", i.e., the place of emphasis in the sentence.  The idea here is that readers naturally look for the “pay-off” at the end of a sentence.  We begin reading a sentence with a sense of expectation that builds as we approach the reward at the end of the sentence.  Our original example does not do this:

The discrete-dipole approximation (DDA) for scattering calculations, including the relationship between the DDA and other methods, is reviewed. Computational considerations, i.e., the use of complex-conjugate gradient algorithms and fast-Fourier-transform methods, are discussed. 

Instead, the first two sentences in the original example end limply with “is reviewed” and “are discussed”.  These sentences leave the reader feeling annoyed by promising, but not delivering information. On top of this, the sentences are more difficult to follow (because of undue separation of subject and verb) and are not very interesting (being written in passive voice).

To revise, I moved the verbs closer to their subjects and tried to place the material to be emphasized at the end of the sentence:

We review the discrete-dipole approximation (DDA) used in scattering calculations and its relationship to other methods.  Other computational considerations include the complex-conjugate gradient algorithms and fast-Fourier-transform methods.


The stress position is where the reader needs and expects closure and the information that is being emphasized ("...complex-conjugate gradient algorithms and fast-Fourier-transform methods."). 
We can summarize the first aspect of the stress position as:  "Save the best for last."  However, we also have to worry about the beginning of the sentence:  the topic position.

The Topic Position

The topic position provides the reader with perspective.  Whatever begins a sentence is what the reader interprets as being what the story is about: "Squirrels hide acorns" vs. "Acorns are hidden by squirrels".  Both sentences are correct, but the first indicates to the reader that the discourse is focused on squirrels, whereas the second emphasizes acorns.  If you use the first version, but your topic is actually oak trees (or seed dispersal), then you will confuse your readers.

This concept of topic position gets tricky when we use first person in technical writing.  With sentences such as: "We review several methods for computing light scattering." or "We studied the role of salinity in determining distribution of coastal plant species.", the emphasis is placed on us, the investigators, rather than on the topic under investigation.  So let's reconsider my revision above.  The second sentence seems fine with respect to subject-verb separation, the stress position, and the topic position:

Other computational considerations include the complex-conjugate gradient algorithms and fast-Fourier-transform methods. 

The topic ("computational considerations") is introduced to the reader at the beginning of the sentence.  The information that is to be emphasized ("complex-conjugate gradient algorithms and fast-Fourier-transform methods") is placed at the end of the sentence, where the reader expects it.  And the subject and verb are in close proximity ("considerations include").

The first sentence, however, has the problem of emphasizing the authors ("We review...") instead of the science topic.  This first-person style is certainly acceptable and not a major problem, in my opinion, if it is used sparingly.  But if we wanted to revise this sentence to adhere to the third principle, how would we do it?  Here is one possibility (I'm making some assumptions here, being unfamiliar with the topic, but it illustrates the point):


The discrete-dipole approximation (DDA) is [often] used in scattering calculations, but its accuracy is unclear in relation to that of other methods.

This sentence now tells the reader what the topic is (DDA), places the point of the sentence (its questionable accuracy) in the stress position toward the end of the sentence, and also explains the "problem" that the paper will address. All the subjects are in close proximity to their verbs.  Although the sentence is now written in passive voice, this is the choice one must make to ensure the reader knows what the actual topic is (acorns vs. squirrels).

The first-person version "We review..." is perfectly fine, as is "This study provides...".  However, the new version puts the actual topic (DDA) in the topic position and also tells us more explicitly why the study needed to be done.  Another option would be to combine the first two sentences:

The discrete-dipole approximation (DDA) is [often] used in scattering calculations, but its accuracy is unclear in relation to that of other computational methods such as complex-conjugate gradient algorithms and fast-Fourier-transform methods.   

This sentence is quite long, but flows well and is easy to understand.  It also prepares the reader for the next sentences that explain what was done and what the results were:


The accuracy of the DDA was tested in computations of scattering and absorption by different targets: isolated, homogeneous spheres and two contiguous spheres. For dielectric materials ((¦m¦ ≲ 2), the DDA permitted calculations that were accurate to within a few percent.

We now have covered the first three principles proposed by Gopen and Swan:


1.    Follow a grammatical subject as soon as possible with its verb.

2.    Place in the stress position the "new information" you want the reader to emphasize. 

3.    Place the person or thing whose "story" a sentence is telling at the beginning of the sentence,  in the topic position.