Writing a Lab Report – the Results Section 2

Writing a Lab Report – the Results Section 2

This section is one of the most important parts of a scientific paper, because it contains the information that will allow you to determine the fate of your hypotheses and predictions.  For that reason, it is vitally important that you present your data clearly.  You should follow the guidelines in the writing handbook that is required for class, as well as the guidelines below.  These guidelines are important to follow because when it comes time to write up the results of your experiments in this (and later semesters) you will lose significant points if you fail to follow these guidelines.  If you are uncertain about this you should always check with your instructor, but some general guidelines to keep in mind are:

1. You need to address every variable you measured in your experiment. If you address it in the methods section, you need to address it here as well. This may involve text, tables, figures, and/or appropriate statistical analyses.
2. The results section must include text in it that explains the data. It cannot simply consist of a series of figures and/or tables.  This text may include results of statistical tests or explanations of the figures that are present in the section.  This text cannot simply say “the data are presented in figure 1” or something to that effect.  It is particularly important to present the highlights of your data.  For example, while you might have a data table that shows the results from a large number of measurements, it would not be sufficient to say “see table 1 for measurements”.  Instead, you should use the text of the section to point out important details and/or provide a relevant summary of the data. For example, you might say “The average height of the plants was 15.2 m, ranging from a minimum of 12 to a maximum of 20 meters.  See table 1 for individual measurements”.  This text gives the reader the main point of the data, points out a relevant point (the min/max of the data) while providing a reference to the table so that he/she can find more data. Note that this description goes beyond just reporting the values of the statistics for the data (although statistics are included as well – we’ll discuss statistics in TLAS 3b).
3. When you interpret the results in a figure or table, there a many things to keep in mind, but some of the most important rules are:[unique_solution]
   1. You need to be certain that what you say is not just a repetition of the information presented in the table/figure – you should not just repeat the numbers from a table or just describe the line on a graph without highlighting something important about the data. For example, examine figure 8 in this handout. You would not want to say that as temperature increased from 25 C to 35 C the amount of CO₂ produced increased, but after that point, further increases in temperature resulted in a decrease in CO₂ In this case you are just using a lot of words describing the shape of the graph without any new information. Your reader should be capable of determining the shape of the graph. Instead what you might say is that there was maximal CO₂ production at 35 C with reduced production above or below that value. In this case you’ve highlighted the most important observation (the maximum point) but you haven’t wasted your reader’s time describing the whole graph.
   2. You also need to make sure that what you say provides an accurate description of the data. It would not be appropriate to simply say that figure 8 shows that the amount of CO₂ produced increased with temperature. This is because CO₂ production did increase up to a point, but once you reached some critical temperature, the production of CO₂ decrease as temperature continued to rise. This requires you to use a more detailed explanation for the figure to show this more complex relationship.
   3. You can (where appropriate) address general trends in your data, but these must also be completely accurate. For example, you could mention that figure 8 seemed to show a linear increase in CO₂ production as temperature increased when below the maximum and a linear decrease at temperatures above the maximum. However, terms like “linear” and “exponential” have very specific, mathematical meanings, so you need to be sure that your use of the terminology is correct. After all, two points are always going to be on a line, so having two data points and saying they have a linear relationship isn’t suitable.
4. You generally will not include all your raw data in a table unless the amount of data is very If you are making a table with every single measurement, you should ask yourself why you are giving them all. In addition, you should look at how likely it is that a person will be able to read your table. If you want to provide all the data, it’s usually better to plot all the data on a graph (such as a scatterplot) and then report descriptive statistics in a table.
5. You should only include tables and figures if they help make your data easier to understand. Always ask what you want the reader to get from your figures before you go to the trouble to include them.
6. When you include a table/figure, it needs to be referred to in the text of the section, and it needs to be located in the part of the paper where it is first addressed. Note that this may apply to figures that you use in the
7. Do not get overly complicated with your figures – 3-dimensional graphs or excessive uses of color and specialized fonts are generally not needed, and often make the graph more difficult to read.
8. You do not make conclusions about your data in this section, you simply report it and summarize it for the reader. Trying to explain what you think the data means is contained in the final section of the paper, commonly called the “Discussion” or “Conclusions” section of the paper (covered in a later TLaS handout).
9. Remember the “hourglass” format for the lab report from TLaS 1. In this section you are focusing on your research primarily so you want to make sure that you avoid going off on unnecessary tangents.

Writing a Lab Report – the Results Section 2

Continuing on with the material addressed in the TLaS 3a handout, you need to be sure to report statistical results appropriately. There are a number of guidelines that you need to follow to do so properly.

1. You need to address every variable you measured in your experiment. If you address it in the methods section, you need to address it here as well. This may involve text, tables, figures, and/or appropriate statistical analyses.
2. Your statistics need to be integrated in other results (including figures, tables, and text). You should give thought to the way that you are presenting the information so that it is easy for the reader to understand
3. You do not provide the full output from your statistical program (e.g., the tables provided by Excel as shown in this handout) or results of calculations, just the required numbers from the test results.[unique_solution]
4. Results of statistical tests are reported in a sentence that follows the following general format: “The results of our test showed no significant difference in the number of times each side of the die was rolled (chisquare, ² = 5.024, 5 df, p>0.05)”. The proper formatting of this sentence is vital to accurately convey your results. It includes the following parts:
   1. Whether the results were significant or not, and, when appropriate, it identifies what the significant difference was (e.g., were the experimental plants shorter or taller than the controls?).
   2. Parentheses with the details on your statistical results. What you include will vary depending on the test you used (see the examples in each section above and in the handbook for the particular statistical program, where appropriate), but will include things such as:
      1. The specific name of the test you calculated (e.g., chi-square, unpaired t-test, etc.)
      2. The value of the test statistic (the chi-square value you calculated, the F-value for an ANOVA or regression, or a t-stat for a t-test).

• Degrees of freedom for the test

1. The p-value for your test. Give the exact value if it was calculated (as in our t-test and ANOVA examples) but if you don’t have exact value it is common to simply report it as “p > 0.05” or “p < 0.05” or something to that effect.
2. Any other values that are needed to interpret your test (e.g,, the R² value for a regression).

1. It is very important that you determine the significance or non-significance of your data correctly. Pay close attention to the p-value and how you obtained and interpreted it. An incorrect interpretation of these numbers will completely change your conclusions.

5. Remember the “hourglass” format for the lab report from TLaS 1. In this section you are focusing on your research primarily so you want to make sure that you avoid going off on unnecessary tangents.