Mentorship notes: The XYZ Rule and The Most Important Question

So, I had been taking a break from my “online presence” of late to prioritize my offline life, but I have had two breakthroughs of sorts lately that I wanted to get written down, even if imperfectly. They both have to do with student mentorship, something that I deeply enjoy—how can I demystify this process of “science-ing” for students? That’s a challenging question to answer, which makes finding relevant tools that work all the more gratifying!

The first of these things is what I will call the XYZ rule. I used to use this rule back when I taught Intro Ecology, but my use of it then wasn’t as clean as it is now. I am sure this is not an original idea, but I am unsure who I would have gotten it from. If you recognize it, feel free to let me know and I will attribute it. Anyway, the rule is actually a sentence:

“If X is true, I expect to see Y when I do Z.”

In this sentence, X is a hypothesis, a statement about how the world might work. Y is either a prediction or a result—something one would expect to observe if X were accurate, or something one did observe, if the data have already been gathered. I used to call Z an experiment, but I realized recently that Z is really just any type of data-gathering process, of which an experiment is just one type. So, to put it all together, “If the world works [in this way], I expect to see [results that look like this], when I [go get the relevant data and summarize it].” This sentence is meant to be an answer to a scientific question. For example, “Why does nitrogen fertilization make leaves greener?” Well, “If nitrogen is an important nutrient for plants because it is an important part of chlorophyll, which is green, then I expect to see more chlorophyll in the leaves of plants fertilized with nitrogen when I conduct a fertilization experiment.”

For me, this “rule” unites the most critical pieces of the project development process: The question, the hypothesis, the data-gathering process, and the predictions/(expected) results. Once you have these well established, you are well on your way to a successful project! At least, that’s been true in my own personal experience. Lately, we have had several students join our lab to conduct independent research projects for their Intro Biology classes. During the mentorship process for these students, especially, I have been finding this rule especially helpful. It helps me take this task that feels so amorphous for many students—crafting a research project—and give it much more specificity. So far, at least, it’s meant that it only takes one or two back-and-forths before the students and I have hammered out a good direction for the project instead of several, so the students must be finding it helpful as well.

What I think is maybe the most important benefit of framing the project design process around this rule is that it leads to what I think is the most important project design question: What will be the graph (or graphs) that you will make at the end of your data-gathering process that will show us whether your hypothesis did/did not have merit? This is how I usually approach the Y part of the XYZ rule; I ask them to consider this question. This is such a useful question to ask for sooo many reasons. Here are a few that come to mind: 1) If a student can’t draw anything, it might be because they don’t know enough about graphs, which is a solvable problem; 2) If a student draws an incomplete graph or a bunch of confusing graphs, they may be trying to gather more (or less) data than they need to actually answer the question they have posed; 3) If a student can’t figure out a graph type or label the axes meaningfully, it may be because their hypothesis is not measurable enough for the subsequent results to be easily graphable; and 4) If a student can’t decide how to arrange the data, they may not have the concepts of the topic down enough yet to know how the variables should relate. In other words, it’s a single question that can reveal any number of issues at a point in the project when it’s still easy to fix them. On the other hand, if the student can answer this question, we now have a firm project endpoint to work toward—we just need to help the student get the data (and the R training, and writing mentorship, and so forth) that will enable them to draw that graph and slot it into the narrative of their paper and/or poster.

So, yeah, going forward, I definitely think these are two mentorship tools I will refine and use: 1) “Show me your question and your XYZ sentence(s) and 2) “What is your graph for the Y part?”

This probably wasn’t the most elegantly written post, but did you find it useful anyhow? Please let me know!