EAS327: A Few Suggestions on Writing Lab Reports

The more conscious you are about writing, the better. How about consulting a primer on writing/technical writing? There are many excellent books - to list a few:

• Writing Clear Paragraphs, Donald et al.
• The Elements of Style, Strunk & White
• Words, Sentences, Paragraphs, Essays, Moyles & Logan
• Communicating in Science, Booth

• Be tidy. As a rule, unless otherwise instructed, in technical writing that will be evaluated or reviewed use double-spacing.

• Importance of an Introduction... In any communication - oral or written - there ought to be a 3-part structure: Introduction, Main Body, Conclusion. The purpose of the Introduction is to gather the reader's attention, remind him/her what s/he is about to read, let him decide if he is interested, set the stage... the Introduction ideally achieves a focusing of the reader's mind from the infinity of all possible thoughts and distractions to something specific you have to say.

  It is a mistake to assume an Introduction is not needed. On the other hand there is no formula for an Introduction, other than avoiding dullness, repetition. Can you start out with something imaginitive, something individual, something provocative? A question? A hypothesis?

• Try to be aware explicitly of your own style. Do I use an essay style or a point style? Do I have neat printing/writing, or is this a deficiency? Ought I to use a word-processor? Are my figures artistic? Or are they, rather, rigorous/technical? Are they simply messy, nondescript, laborious, boring? Does my work give a good visual impression?

• One of the key challenges in writing is to give the reader a sense of pace, that s/he is rapidly and efficiently traversing your material. How do you achieve this? Again, there is no recipe, but these things help:
  • Use carefully chosen, informative headings (but don't go overboard with sub-sub-sub headings)
  • Be conscious and intentional about the effectiveness of your transitions from one paragraph to the next. If you don't know what this means, maybe do some reading; a good writer has a sense of natural transition from one paragraph to the next.
  • Be compact
  • Specifically direct the readers attention: eg. "Please refer to Figure 1 (attached) for Observed Step Response of the RC Lowpass Filter." Or again, "Please refer to Table 1, which lists the resistors (R₁, R₂, R₃, R₄) comprising our Wheatstone Bridge, and the theoretical (ΔV^T) and measured (ΔV^M) error-voltage (ie. bridge imbalance) for each choice of resistors."
  • In particular, a stack, plain and simple, of Tables and Graphs, stuffed one after the other and stapled together, does not make for an effective report. It is your job as writer to provide the logical connexions ("signposts") for the reader. One might call this task the "integration" of your technical results, as captured in your Tables and Graphs, into a coherent report.

• For your graphs, use real graph paper... not just lined writing paper, or the "big squares" writing paper. Graph paper has a mesh size of order 1mm, and can be bought at the university bookstore. Alternatively, use a computer graphing program: and if you take this latter course, don't spoil it by super-posing a hand drawn line.

• Go wild in labelling graphs and figures and tables. Label all axes as completely and helpfully as you can, giving units, of course. Add a title. Clearly demarcate measurements from theory.

• Use Tables creatively and informatively - with suitably detailed titles and legends - to save space. Represent and identify signals (in your tables and elsewhere) by introducing - and defining - some compact symbol. For example a signal that (verbally) might be defined as "Relative humidity according to the second Campbell Scientific 207 Probe" could be symbolised as "RH_C2". Introducing symbols allows you to write more compactly. And by the way, if your identifiers are verbal (as in the example above) then they will dictate the column widths in your tables - making for awkward, ugly tables.

• Don't underestimate the effectiveness of a key diagram that summarises the experiment you have performed. A well-executed, stylish - and correct - figure, can set your work apart. Try to develop your own style. Be artistic if that suits you, otherwise be technical. Don't spare the detail, use colour effectively. Don't try to fit it on a pin-head. Compare these examples:
  • Size was 2.5" by 7"
  • Size was 2" by 7"
  • Size was full 8.5 x 11" page
  • Size was full 8.5 x 11" page
  • Size was full 8.5 x 11" page

• Take the trouble to check your spelling. How about these miss-spellings of the company name "Vaisala," all in the same report! - "Visula," and "Viasalla," and "Visalla," and "Viasalla." It is not a good idea to irk your reader this way! Again, who ever heard of an "eponential" or an "expodential" curve?

• Where using data-loggers, report:
  • nature of the input signals
  • details of the logger program: in particular the sampling interval Δt, and the averaging interval (T) if averaging was performed. Also any key data-reduction steps performed by the logger (eg. conversion of measured voltage V to a function a_o + a₁ V + a₂ V² +...). Remember, in your Lab Report you can demonstrate you were attentive to detail, curious; that you are technically-literate and competent.

• Avoid pointless repetition.

• Do as instructed... if told to determine internal resistance (R_s) of a sensor then give a value for R_s... don't just quote the various measured voltages whence the value of R_s is implied.

• Look out for deficient or incomplete ideas. Eg., "The RC filter had a very short response time." The idea of short always begs a standard of comparison - short compared to what?

• Be concrete. Don't write "internal resistance of the signal generator was 50 ohms." Write "internal resistance of the HP ??? signal generator was 50 ohms." Such details prove you were attentive to detail, fully involved in the experiment.

• Give appropriate numbers of significant figures. For example, if you read a voltage from a multimeter, don't cite (eg.) "4 volts." The multimeter will be capable of providing at least one and probably two meaningful decimal places... 4.00 volts.

• Don't indulge in vague, shallow, meaningless analysis or justification. If you can't think of something precise and pertinent to write, write nothing.

• Don't give "Feel Good" Conclusions - like, "Overall the lab was effective in introducing us to the basics of..." Express some particular insight, show that you learned - by asking a question, pointing up a fault or an assumption in the lab, something.

• Symbols in diagrams must match symbols used in equations.

• On a graph or in a table, don't fail to compare measurements with theory, when theory is available.

• Set your tables and figures apart from the text, perhaps in boxes, with good separation. Make it easy for the reader to follow the flow of text. Point your reader to your tables and figures where appropriate, by referring to them by their number, in the text.

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Last Modified: 7 Jan. 2005 (minor corrections incl. font, 26 Mar. 2016)