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Common Errors in Student Research
Papers From Rice University-- Created by David
R. Caprette (caprette@rice.edu), Rice University 31 Jul 96.
Updated 20 Aug 07 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. 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. 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. 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. 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." 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. 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. 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. 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.' 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]. 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. 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. |