Data cards are a wonderful way for students to get a feel for data. As a University lecturer in the 1990s, I found that students often didn’t understand about the multivariate nature of data. This may well be an artifact of the kind of statistics they studied at school, which was univariate (finding the confidence interval for the mean of a set of numbers) or bivariate at best. And back then, when statistical analysis was done by hand calculation, this was all you could expect. How times have changed!
At the NZAMT (NZ Association of Mathematics Teachers) conference in 2015, both Dick de Veaux and Rob Gould suggested in their keynote addresses that students need to be exposed to multivariate data. Rob endorsed the use of data cards to enable this. Data cards are a wonderful tool for all levels of learning. In the New Zealand “Figure it out” series, there are several lessons that use data cards, generally made by the students themselves. We were inspired by this and have developed a set of 240 data cards with information about dragons, to help teachers and students learn and be successful in their statistical endeavours. In an earlier post I discuss the pros and cons of fictional data.
The Dragonistics data cards are now available to purchase, and we have a range of supporting materials for lessons and activities at various levels. You can find out more about data cards by clicking on this link.
Using data cards gives a wonderful opportunity to explore the concepts of evidence and of distribution. The students lay out their cards in a nice bar chart arrangement, and say, “See – there is a difference.” Teachers should then ask for evidence. Students need to be able to articulate what evidence there is for the effect they have observed, and place it in context. We have found this to be a useful process when teaching students of all levels.
With regard to distribution, if we work only with numbers, and find the medians of the two groups and observe that the median is higher for one group than the other, this is rather limited information. By observing the distribution of the dragon cards between the two sexes, we can see that there is overlap. It is not a clearcut difference. Additionally we may observe other effects, such as due to colour, which we might like to explore further in another journey around the Statistical Enquiry Cycle.
It is fascinating that the concept of data cards is so new. It seems like an obvious idea, and makes concrete some very tricky abstract ideas. Data cards are useful at almost any level of understanding. As the need for understanding of statistics grows, there has been an emphasis on finding out better ways to teach for understanding. Clearly data cards are a win!