Saturday, 21 January 2017

Changing percent of students at each PISA math proficiency level

This is a graphical summary of how Canadian students have trended in the triennial math tests offered by the PISA/OECD consortium.

It is not so much about their international standing, but about how their achievement levels have varied over the five rounds from 2003 through 2015.

For each participating region or country, PISA publishes how the students’ grades are distributed across seven different proficiency levels. The levels are the same for all jurisdictions, and they have remained the same for the five rounds since 2003.

The grades defining the boundaries of the proficiency levels are shown in boldface. (The ones in parentheses are what you get when the PISA-assigned grades are converted in a reasonable way to grades out of 100.)  The yellow and blue levels identify low performing and and high performing students. The interval widths for each of Level 1 through Level 5 are the same. PISA does not define the widths for the lowest (less than Level 1) and highest (Level 6) proficiency levels.

The table below summarizes the distributions for Canadian students for each of the five PISA rounds.

In effect, each row of the table is an estimated probability distribution. For example, if you were to randomly choose a Canadian student in 2003, the probability that he or she would have achieved Level 5 is 14.8 percent.

Actually, the reason I wrote this post was to try to figure out how to use slides in blogger -- I think slides give a more vivid visual depiction of the changes than a table does.

The following slideshow displays the table as a sequence of histograms. There is some concern that Canadian students are trending in the wrong direction. Perhaps this graphical representation may help you decide if the trend is cause for alarm.