I am old enough that I have both observed and given presentations on clear film with an old school overhead projector. I was thinking about time and visualizing time and studying statistical process control and using charts to help with decision making. Suddenly, I had a perfectly clear visual of a stack of overhead film with run chart plots overlaid with each other for comparing data.
Statistical Process Control, specifically Run Charts (a line graph where a measure is plotted over time), are useful tools that allow us to:
- Display data to make process performance visible
- Determine if a change resulted in improvement
- Assess whether improved performance has been sustained
What does that have to do with my overhead projector moment?
Let’s use a legal example. Perhaps I want to see my time working in one practice area compared another. A run chart will help me see if there are patterns. If I have some data (which is available in my time and billing system), I could plot that in a run chart. Comparing data in an overlay format works well if you can keep the scales for the charts the same. If the scale is too dissimilar, I can reformat the data by showing both sets as percentages of a whole. If I have lots of data, I can plot averages or rational subgroups.
Maybe I just want to compare my billable time before and after an event (hiring staff, new client group, research questions answered in CanLII vs. a fee based service. It is pretty easy to make a chart in Excel and visualize data.
What is the point (pun intended). Plot points that appear on a visual chart are much easier to pick out than if you are looking at a list of numbers. Visualizing data makes decision making based on that data an easier task.