This is not an exhaustive list. With every new lab protocol,
you folks come up with the darnedest ways of messing up
a perfectly good paper. However, if you heed the comments
here your reports stand a much better chance of being mistaken
for professionally written research papers.
Quotes
When you write a paper related to literature, history,
current events, and many other fields, direct quotes may
be essential to a full discussion of the subject. In science,
there is very rarely any call for a direct quote. On student
papers, there is no reason at all to include direct quotes,
except in the case when the student doesn't understand
the concept and uses the quote to avoid having to explain
it his/herself. Obviously, this doesn't go over too well
with the grader. As a rule, do not use direct quotes in
a scholarly technical paper. Your own thoughts must be
expressed, not those of someone else.
Verb tense
Use of the wrong verb tense, at best, is irritating to
read and reflects poorly on the student's writing skills.
At worst, the reader can be confused as to what facts are
already known and what was newly discovered in the actual
study that is the subject of the paper. As a rule, use
past tense to describe events that have happened. Such
events include procedures that you have conducted and results
that you observed. Use present tense to describe generally
accepted facts.
We sought to determine if
mating behavior in Xiphophorus helleri is related
to male tail length by placing combinations of two male
fish with different length tails in the same tank with
a female fish.
We found that protein synthesis
in sea urchin embryos treated with actinomycin D was considerably
less than in untreated embryos. This finding agrees with
the model stating that protein synthesis in 24 hour sea
urchin embryos is dependent on synthesis
of new messenger RNA.
Reference to results of a specific study should also be
in past tense.
Abercrombie and Fitch reported that
30% of the public is allergic to wool.
Mixing tenses is even worse - this sort of thing hurts
my ears. Unfortunately, the people who read the news in
television and radio broadcasts are frequently unaware
of verb tense at all.
Two guys rob a liquor store downtown.
The robbery occured at midnight last
night.
[from a newspaper article] Two inmates hide in
trailer to escape S.C. prison.
The last one had me puzzled. I was thinking, if they know
the inmates are in the trailer, why don't they just go
in and get them? What the article actually reported was
that the two had hidden in a trailer which was driven out
of prison, allowing them to escape. I grew up speaking
and reading English (the American version, that is). Imagine
the difficulty faced by a non-native speaker who learns
proper English and then reads the local rag or tries to
make sense out of reports by "talking heads" on
new shows.
Proofread!
Incomplete sentences, redundant phrases, obvious misspellings,
and other symptoms of a hurriedly-written paper can cost you.
Please start your work early enough so that you can proofread
it. Check spelling of scientific names, names of people, names
of compounds, etc. Spelling and grammatical errors can be embarrassing.
Since many very different terms have similar names, a spelling
error can result in a completely incorrect statement.
When you print off your paper, please make sure that tables
are not split over more than one page, that headings are not "orphaned," pages
submitted out of sequence, etc. Remember, someone has to read
this thing! If the reader is an editor or reviewer, you might
get a rejection notice because you were too sloppy.
Irrelevant information
Anecdotal information
Sometimes you may feel the need to justify a statement or
procedure by stating "'the instructor told us to do this
instead of that." You might think it appropriate to write "we
used Microsoft Excel to produce a graph of x versus y." Such
information is anecdotal and is considered to be superfluous.
In some cases omission of anecdotal information is unfortunate.
Papers in the older literature tend to be a lot more exciting
and often more informative for those not 'in the know,' because
the researcher could report how a conclusion was reached, including
the reasoning and various sidetracks that led him/her to conclusions.
The writer could actually tell the story of the investigation
process. Modern papers omit such information because the volume
of literature is so great, most of us doing a search don't
have time to wade through more material than we need. Publication
costs are too high to permit printing of superfluous information.
A research paper summarizes a study. It does not identify
who did what. Reference to instructors, fellow students, teams,
partners, etc. are not appropriate, nor is it appropriate to
refer to "the lab."
Unnecessary background
If you state facts or describe mechanisms, do so in order
to make a point or to help interpret results, and do refer
to the present study. If you find yourself writing everything
you know about the subject, you are wasting your time (and
that of your reader). Stick to the appropriate point, and include
a reference to your source of background information if you
feel that it is important.
Including material that is inappropriate for the readership
It isn't necessary to tell fellow scientists that your study
is pertinent to the field of biochemistry. Your readers can
figure out to what field(s) your work applies. You need not
define terms that are well known to the intended readership.
For example, do you really think it is necessary to define
systolic blood pressure if your readership consists of physicians
or cardiovascular physiologists?
Subjectivity and use of superlatives
Technical writing differs from the writing of fiction, opinion
pieces, scholarly English papers, etc. in many ways. One way
is in the use of superlatives and subjective statements in
order to emphasize a point. We simply do not use such writing
styles in science. Objectivity is absolutely essential.
Subjectivity refers to feelings, opinions, etc. For example,
in your discussion you might write, "We felt that the
fixative was bad, because we had difficulty finding flagella
on our Chlamydomonas." Another researcher is unlikely
to risk time and resources on the basis of your "feeling." On
the other hand, you might write, "The percentage of cells
with flagella was inversely proportional to the time they spent
in fixative, suggesting that the fixative was causing cells
to shed flagella." This is information that another scientist
can use.
Superlatives include adjectives such as "huge," "incredible," "wonderful," "exciting," etc.
For example, "the mitochondria showed an incredibly large
increase in oxygen consumption when we added uncoupling agent." Your
definition of incredible might be different from that of someone
else - perhaps a five fold increase is incredible to you, but
not for the next person. It is much better to use an objective
expression, such as "Oxygen consumption was five fold
greater in the presence of uncoupler, which is a greater change
than we saw with the addition of any other reagent."
Similarly, we don't write that we believe something. We present
the evidence, and perhaps suggest strong support for a position,
but beliefs don't come into play. In particular, we do not "expect" a
particular set of results, or "wire" a hypothesis
so that it appears that we correctly predicted the results.
That sort of practice is another example of lack of objectivity.
Proof
See my essay on
fact, hypothesis, and theory. The requirements for scientific
proof are extremely rigorous. It is highly doubtful that any
single experiment can be so well controlled that its conclusions
can be regarded as proof. In fact, for any result to be accepted
it must be confirmed independently. In fact, we can never know
if a model as we describe it presents an accurate picture of
any natural process. We can never look at the original blueprint
to check our conclusions. So... your data may strongly support
a position, or they may allow you to reject a hypothesis, but
they aren't likely to provide anything close to proof.
Grammar and spelling
Please avoid obvious grammatical errors. Granted, you aren't
writing an English paper (heck, an English teacher would tear
my own writing style to shreds). However, clear written communication
requires proper sentence structure and use of words. Make sure
that your sentences are complete, that they make sense when you
proofread, and that you have verb/subject agreement.
Spelling errors in a paper make you look amateurish. For example, absorbance is
read from a spectrophotometer. You don't read absorbencyfrom
a spectrometer. Worse, they can change the entire
meaning of your writing. One letter changes the chemical compound
you describe. I know the action of cycloheximide in
eukaryotic cells, but I do not know the action of cyclohexamide.
Inaccurate word or phrase
Changing temperature had the following affect on
the subject.
'Affect' is a verb. 'Effect' is a noun. What happened to the
subject was an effect. The temperature change affected the subject.
Please learn the difference.
The data lead to the assumption that x has
no relationship to y.
If you base a conclusion on data, then your conclusion is a deduction,
not an assumption. In fact, in experimental science assumptions
are usually avoided. A purpose of controls is to eliminate the
need to assume anything.
Our inability to ensure that all cells in the population
were in the same stage of development skewed our data.
This statement doesn't reveal very much. The writer intended
to say that the data points were more scattered, that is, the
non-uniformity of the population resulted in unacceptably high
experimental error. The word 'skew' means 'having an oblique
position; turned or twisted to one side; slanting; sloping.'
It can be used as an adverb or noun as well. In statistics, the
word refers to an asymmetric distribution of data. Nowhere in
the definition is there any reference to the state of being incorrect
or more scattered. Thus, not only is the word overused, it is
also misused.
We rationalized the finding that blocking
the sodium pump had no affect on uptake of glucose by suggesting
that the symport mechanism depends solely on the sodium gradient,
which persists long after the pump is shut down.
A definition of 'rationalize' is 'to explain or justify.' Another
is 'to attribute logical or creditable motives to actions that
result from other, perhaps unrecognized, motives.' In short,
to make excuses. As I learned in English class a long time ago,
the term's principal usage is to attempt to justify something
on dubious grounds. For example, 'he rationalized his poor behavior
by saying that he had just broken up with his girlfriend and
was distraught.' The definition does not include anything about
the explanation being valid, therefore another word would be
preferable. Try
A likely explanation for the finding...is
that...
The word 'data' is plural. However since investigators usually
refer to sets of data, there is a tendency to use the word as
though it was singular. Hence a writer will state, 'the data
was affected by the phase of the moon,' or 'the data suggests
that phase of the moon has no effect on mood.' As awkward as
it may seem to you, the proper phrases are, 'the data
were affected...,'
and 'the data
suggest...' By the way, the singular form
is 'datum.'
Oversimplification
We used a spectrophotometer to determine protein
concentrations for each of our samples. We used an oscilloscope
to measure resting potentials in crayfish muscle.
The spectrophotometer or oscilloscope may be a novel, mysterious,
and versatile device to you, but I suspect that even an expert
biochemist would have a hard time finding a protein concentration
using only a spectrophotometer. The first statement leaves
out the dye reagent, standards, pipettors, etc. that are required
to perform the assay. The second statement omits any reference
to the micropipets or the specialized electronic instrumentation
that is required in order to measure transmembrane potentials.
What information did you intend to convey? If you intend
to describe the methodology, then write a complete description.
If you intend only to summarize the procedures then you might
seek a phrase that sums up what was done without oversimplifying.
For example, "We used a colorimetric assay to determine
protein concentrations in each of our samples." Or, "We
measured resting membrane potentials using KCl-filled micropipets
with a microprobe system from [supplier and/or reference].
Superficiality
The purpose of a discussion is to interpret the results,
not to simply state them in a different way. In most cases
a superficial discussion ignores mechanisms or fails to explain
them completely. It should be clear to the reader why a specific
result came to pass. The statement, "The result agreed
with the known theoretical value," tells us nothing about
the mechanism(s) behind the result. What is the basis for expecting
a particular result? Explanations may not be easy and your
explanation may not be correct, but you will get most or all
of the available credit for posing a reasonable explanation,
even if it is not quite right. Superficial statements, on the
other hand, will cost you.
Anthropomorphism
Sometimes you cannot easily find the right wording in order
to explain a cause and effect relationship, or you may not
understand the concept well enough in order to write an explanation.
Anthropomorphism is a type of oversimplification that helps
the writer avoid a real explanation of a mechanism. A couple
of examples should make the point for you.
Sodium wants to move down the chemical gradient toward
the compartment with the lower concentration.
The thought behind the statement is correct, but the statement
does not represent the correct mechanism. Sodium has no free
will. It tends to move toward the compartment with lower concentration
because the probability of a sodium ion moving through a channel
on the more concentrated side of the membrane exceeds the probability
that an ion will move through a channel on the less concentrated
side. If you don't want to explain the principle behind osmosis,
you can simply state that osmotic pressure tends to drive sodium
from the more highly to less highly concentrated side of a
membrane.
The ETS works furiously in a vain attempt to restore
the chemiosmotic gradient
Wow. Well, the adverb "furiously" is not only subjective,
but it normally applies to a deliberate action. We know that
the ETS (electron transport system) is a set of carrier complexes
embedded in a membrane, and that it cannot be capable of a deliberate
action. Something that cannot act deliberately cannot think,
either. There is a physical cause and effect relationship between
the ETS and the chemiosmotic gradient that does not require attributing
a free will to any part of the system.
Common mistakes in reporting results
Converted data are data that have been analyzed, usually
summarized, and presented in such a way that only the information
pertinent to the objectives of the study is presented. Raw
data refers to results of individual replicate trials, individual
observations, chart records, and other information that comes
directly from the laboratory.
Once you have presented converted data, do not present the
same data in a different way. For example, if the data are
plotted, then don't include a table of data as well. Present
a figure (such as a graph) if appropriate. If the data are
better represented by a table, then use a table. The caption
with any figure or table should include all pertinent information.
One should not have to go into the body of the paper to find
out the results of statistical tests on the data, or the rationale
behind a curve fit.
Raw data are not usually included in your results. Raw data
include lists of observations, meaurements taken in order to
obtain a final result (e.g., absorbance, relative mobility,
tick marks on a microscope reticule).
Use an appropriate number of decimal places (if you need decimal
places at all) to report means and other measured or calculated
values. The number of decimal places and/or significant figures
must reflect the degree of precision of the original measurement.
See our analytical resources for information on uncertain quantities
and significant figures. Since the number of significant figures
used reflects the level of precision of the measurement or
calculation, there is never any need to qualify a measurement
or calculation as 'about' or 'approximate.'
Graphs and other pictures that represent data are called figures,
and are numbered consecutively. Tables are distinguished from
figures, and are numbered consecutively as well. For example,
a paper with two graphs, a reproduction of a segment of chart
record and two tables will have figures 1, 2, and 3, and tables
1 and 2. Do note that I distinguished graphs from chart records.
Not everything with gridlines is a graph. Graphs are analytical
tools. Chart records are raw data (which may be presented in
results as an example, if appropriate).
Do not draw conclusions in the results section. Reserve data
interpretation for the discussion.
The significance of 'significance'
We have a statistically significant difference when analysis
yields a very low probability that the difference was due to
sampling error (random error) alone. If sufficient data are
collected, and statistical significance is not achieved, the
investigator can conclude that the null hypothesis is supported ñ there
is no significant difference.
Lack of a significant difference does not mean that the result
itself is insignificant. A finding, for example, that there
are no intrinsic differences in fundamental mathematical ability
among racial groups would be a very significant finding. Significance
in this study refers to the importance of the result. "It
is significant that we found no significant differences among
the groups studied" is a valid, though perhaps confusing,
statement.
There is a tendency among students to reject a study as inconclusive
just because no statistically significant differences were
found. Such rejection suggests a misunderstanding of the scientific
method itself. You can conclude something from even the most
poorly designed experiments. In fact, most well-designed experiments
result in support for the null hypothesis. Be prepared to interpret
whatever you find, regardless of what you think you should
find. The purpose of experimental science is to discover the
truth - not to make the data conform to one's expectations.