written reports suggestions for good scientific writing
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Written ReportsSuggestions
for Good Scientific Writing
John E. SilviusProfessor of BiologyCedarville University
Written ReportsSuggestions
for Good Scientific Writing
Part I
General Suggestions
Written ReportsSuggestions for Good Scientific Writing
1. You may use first person plural (e.g. We estimated plant cover by using a …) or passive voice (e.g. Plant cover was estimated by …) 2. Place the subject of each sentence as early as possible in the sentence. Poor: “In order to determine plant height diversity, we measured …” Better: “Plant height diversity was based upon 3 Robel pole measurements…” 3. Make two concise sentences rather than a long string of clauses. 4. Be precise so that the reader could repeat your “Methods” and obtain your materials and instruments from your wording or via citation of Lab Manual.
Writing METHODS – A Few Suggestions
Cedarville U. Prairie RestorationRank-Abundance: August, 2001 and Sept., 2002
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Abundance Rank (Top 28 Species)
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i) 20
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Figure 1
2001
2002
Figure 1. Rank-abundance curves for plant species of the Cedarville University Prairie Restoration, based on quadrat sampling during two different summers. A slightly greater species evenness was evident among the ten most abundant species in 2001 compared to 2002. Such comparisons, however, must consider the larger sample size in 2001. The 52 quadrat samples in 2001 expressed a more accurate estimate of species richness than the 19 samples in 2002.
What’s in this figure?
Where?
Method?
Brief interpretationor save detail for
“Results” if instructed.
Writing a Figure Legend
Cedarville University Prairie RestorationRank-Abundance Curves for Two Consecutive Years
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0.05
0.10
0.15
0.20
0.25
1 3 5 7 9 11 13 15 17 19 21 23 25 27
Abundance Rank (Top 28 Species)
Prop
ortio
nal A
bund
ance
(P
i)
0.00
0.05
0.10
0.15
0.20
0.25
2001
2002
Figure 1. Rank-abundance curves for plant species of the Cedarville University Prairie Restoration, based on quadrat sampling during two different summers. A slightly greater species evenness was evident in 2001 compared to 2002. Such comparisons, however, must consider the larger sample size in 2001 (52 quadrat samples) as compared to 2002 (19 samples).
Preparing Figures:Read the “bubbles” to understand the intent: Chart title explains
subject under investigation and its
location and time frame. Axes labels
give parameters.
Legend repeats chart title (what-where-when), and cites “Methods” (how)…
…and, notes any cautions.
…then, helps reader interpret
the data...
Suggestions for Good Scientific Writing
Suggestions for Good Scientific Writing
Preparing Figures: Some ExamplesRead the “bubbles” to understand the intent: Chart title explains
subject under investigation. Axes labels give
parameters.
Legend repeats chart title (what-where-when), and
refers to “Methods” (how)…
…then, helps reader interpret
the data...
Suggestions for Good Scientific Writing
Preparing Figures: Some ExamplesRead the “bubbles” to understand the intent:
Legend states the“what-where-when”
…then, helps reader interpret
the data...
Written ReportsSuggestions for Good Scientific Writing
SENTENCE A:“Table 2 shows that the most dominant plant species are Indian Grass and Tall Goldenrod.”
SENTENCE B:“The most dominant plant species of the prairie restoration site based upon random plot sampling are Indian Grass and Tall Goldenrod (Table 2).”
Which of the following sentences states the experimental results best?
Writing RESULTS or DISCUSSION:
SENTENCE A:“Table 2 shows that the most dominant plant species are Indian Grass and Tall Goldenrod.”
Concise Scientific WritingSuggestions for Good Scientific Writing
You need not “show” the reader the data.
See reference to “(Table 2)” in SENTENCE B.
But how is this judged?Include reference to
method used to determine (see Sentence
B.
“Table 2” above makes
a poor subject. See SENTENCE B.
RESULTS -- critique of SENTENCE A:
SENTENCE B:“The most dominant plant species based upon random plot sampling are Indian Grass and Tall Goldenrod (Table 2).”
But how are “dominants” judged?Include reference to
method used to determine (see Sentence
B.)
Written ReportsSuggestions
for Good Scientific Writing
Part II
Using Statistics in Your
Results and Discussion
Written ReportsSuggestions for Good Scientific Writing
SENTENCE A:“Figure 1 shows that plants grown under high light intensity had longer stem internodes as shown by our t-value of 2.81 which was significant p < 0.05 for 12 degrees of freedom.”
SENTENCE B:“Increased light intensity caused significantly greater internode elongation in radish plants (p < 0.05) (Figure 1).”
Which of the following sentences states the RESULTS best?
Writing RESULTS – Referring to Statistical Testing
Concise Scientific WritingSuggestions for Good Scientific Writing
SENTENCE A:“Figure 1 shows that plants grown under high light intensity had longer stem internodes as shown by our t-value of 2.81 which was significant at the 95% level for 12 degrees of freedom.”
SENTENCE B:“Increased light intensity caused significantly greater internode elongation in radish plants (p < 0.05) (Figure 1).”
You need not “show” the reader
the data. See “(Figure 1)” in SENTENCE B.
The t-value itself is not significant. Rather it may indicate that the
difference between two means is significant.
You need not go into this detail in RESULTS if you have explained what statistical test you used
in METHODS.
Your variable (light
intensity) should be the subject. See SENTENCE B
RESULTS -- critique of SENTENCE A:
SENTENCE B:“Increased light intensity caused significantly greater internode elongation in radish plants (p < 0.05) (Figure 1).”
Concise Scientific WritingSuggestions for Good Scientific Writing
SENTENCE A:“Figure 1 shows that plants grown under high light intensity had longer stem internodes as shown by our t-value of 2.81 which was significant at the 95% level for 12 degrees of freedom.”
Here is a critique of two sentences which refer to statistical probability.
Low probability supports your claim of “significantly greater” meaning that you can reject Ho with < 5% chance of Type I error. “Methods” will note that you used t-test.
The “significantly greater” indicates that you have based your claim on statistical tests
(see blue bubble below).
Reader encounters subject first
Reader will know where
to find data by this brief reference.
Exhibit A: The probability suggests that disturbance does not enhance species richness (p > 0.10; Table 2).
Poor subject Good (biology) subject
Exhibit B: The null hypothesis for species richness per sample shouldnot be rejected. What was treatment in question?
“Statistics subject” “biology is object of prep.”
Exhibit C: According to the calculated “p” value (p > 0.10), soil disturbance does not have an effect on species richness because there is more than a 10% chance that our null hypothesis
would be correct.
Can you fix this one? Mid-summer mowing did not affect species richness (p > 0.10).
Omit so “bio subject” is up front
● ●♦(
Table 2. [Enter descriptive legend here when table is complete]Parameter Control Disturbed
Total Sample Points (n) 15 36Statistical Analysis of Response Variable Means:
Control Disturbed df t-value pSpecies Richness per Sample 10.8 12.5 49 1.53 > 0.10
Mean Cover
Additional Parametersof your choice
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