Back in the lab, conducting the second round of experiments, you – annoyingly – find yourself in a situation similar to one you have faced before.
One of your data points looks completely wrong. This time, however, you are pretty sure that you yourself caused the strange data. If you accidentally pollute your sample, you would expect exactly the kind of strange data that you have. Pollution can easily happen in this particular experiment.
You run the second round of the experiment again, taking special care to avoid pollution. This time the data looks as you expect.
You kept notes on both runs in your logbook, but do you mention the erroneous measurement in your report? It will take up space, and it might also make you look sloppy as this is not the first time you make an error.
