In 2012 the National Post ran an article by Joe O’Connor where he argued that couples who don’t have children are selfish. It certainly generated a lot of mail, and I imagine that was the point of running it. Joe’s premise that couples who choose not to have children are selfish was probably meant to start arguments and drive readership, and I’ll admit, it caught my eye. But the REALLY interesting facet of that article wasn’t in the writing at all. It was in the graphic that accompanied it.

There have been quite a few stories generated by the last batch of census data, and certainly there are a lot of fascinating implications coming from this work. So it’s not surprising that in this story the National Post would include some data showing changes in family structure in Canada over the last thirty odd years. But, one of these graphs caught my eye, and the more I looked at it, the more I realized that it is patently wrong.


National Post: September  19 2012

National Post: September 19 2012

Look at the graph for the Distribution of Same Sex Couples. Notwithstanding the fact that there was no discussion of same sex couples in the article, so therefore no reason for this graphic to be included, it seems to suggest that there has been a dramatic increase in the number of same sex couples in Canada between 2006 and 2011. In fact, it looks like the number more than doubled between those years, and mostly in the subcategory of married couples. But, if you look closer you see that the numbers that make up each category are stated. Adding the provided number of married and common law same sex couples in 2006 gives us 45,320. In 2011, that number increased to 64,575. A large increase, yes, but certainly not more than double. In fact, if you graph these values you get a much more modest graph that looks like this:

What the Data SHOULD Look Like.

What the Data SHOULD Look Like.

Graphs are often manipulated to emphasize aspects of the data, and quite often we don’t have the skills or comfort with mathematics to look critically at them. This graphic went uncommented for a week, and it’s only because I’m teaching a course on numeracy that I even stopped to look at it anyway. Most of the time, even those of us who like numbers and math would see that graph, think, wow, that’s a big increase in same-sex couples, and move along with our lives. Why? Because we live in a largely math-illiterate society.  We live in a society where it’s common to believe that if a number hasn’t been chosen in the 6/49 draw lately, it must be more likely to be chosen in the next draw. We live in a society where you can hear a weather forecaster say “the chance of rain on Saturday is 50%, and the chance of rain on Sunday is 50%, so there is a 100% chance of rain this weekend.”

Mathematical illiteracy is a big problem, because these skills are crucial in business, science, medicine, and politics, and, as it turns out, crucial for reading the newspaper. If you think you’re immune to sloppy thinking where numbers are concerned (and I know I’m not immune!) imagine shopping for kitchen appliances, or sporting equipment, or clothes. I often decide not to buy something because it’s too expensive, but studies have shown that regardless of the price, we are more likely to buy something if there is a more expensive model sitting right beside it.  That’s because the only thing better than buying something new is buying something new and thinking you got a deal on it. We are all influenced by the numbers around us, and without the tools to interpret what we see, we can be manipulated very easily.

We really need to examine how we teach math and how math is represented in popular media, and a good start is to be very critical of statistics and data that are presented to us. This isn’t to say that we should completely distrust anything numeric, which actually makes the problem worse – a bad case of throwing the baby out with the bath water. Instead, we need to relearn how to think about math. Mathematics is a powerful tool and an incredible language for describing the world. There are countries where math is not considered the realm of the irredeemably nerdy, and Canada is in danger of losing our edge on not just science and technology, but economically and politically, if we don’t learn to speak this crucial language.