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Scientific Experiments
       Most “experiments” carried out in school classes are exercises, rather than actual experiments. An exercise is usually a single trial with a single result that reinforces a desired concept. In actuality, a scientific experiment is repeated multiple times to collect data that can lead to conclusions that either support or refute hypotheses. As Ernst Mayr noted in Towards a New Philosophy of Biology, in the nineteenth century “the controlled experiment was considered the only respectable scientific method, whereas observation and comparison were viewed as considerably less scientific.” Unfortunately, this still has an influence on many people’s perspective.
       In the summer of 1969, I worked at the Biological Image Processing Lab at MIT’s Research Lab or Electronics. I was working on a program that would allow a computer to scan slides to separate out those that showed potential evidence of sickle cell anemia which could then be viewed more carefully by medical staff. A decade later, I spent part of a summer working with my father, carrying out repeated trials of his Irristat, an advancement in irrigation technology. These were examples of actual experimentation.
       When Edison was inventing the light bulb, he carried out over 3000 experiments between 1878 and 1880, seeking meaningful feedback. I remember later learning in an interview that the inventor of the plastic soda bottle carried out over 10,000 experiments to work out optimal conditions to meet the desired needs. These are drastically different from the experience our students get in their science classes!
       The mistaken image of experiments based on school labs may have a lasting negative impact on our society. It may contribute to the public questioning of why scientific experts change their minds and offer qualified conclusions. An all too visible example is professional feedback regarding COVID-19. This uncertainty in science is because the input and evidence continue to change. The public distrust may be in part the result of what people experienced in most science classes!
       Back when I was in high school, I was the manager of the school’s basketball team. Volunteers would help at games, recording where members made shots and which ones went in. Analyzing this data helped work out practice and advice for team members. An important point was that no single game told how well someone played. Enough data was needed to see patterns. Similarly, weather predictions are based on the analysis of existing information and observed patterns. In both cases, patterns and probabilities are involved – not simple black-or-white results.
       As a chemistry teacher, when my students were learning solubility, a lab would be done where each team worked with a different solution concentration. Pooling their results, they were able to fairly confidently identify the solute by seeing the results’ pattern and comparing that to a graph in the text. I also had students do experiments where no procedure was supplied. They had to actually experiment to reach a conclusion, such as finding out how many moles of chalk were required to write out Avogadro’s number (the number of items in a mole). Each team had different measurements, but analyzing the data let them work out good results.
       In the beginning of the year, I held a seminar on graphing. I used a scatter plot of a previous year, looking at the relation of missed assignments to the final grade. While the figures for individual students varied, they could discern that there was a correlation between the two factors. Having the information regarding about a hundred students let them see that there was an actual pattern, even though there was a range of variation.
       This aspect of experimentation needs to be included in school classes. It will better enable individuals to understand and interpret information that appears in news reports. An important concept people should learn is that uncertainty is an aspect of scientific research.
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