14 May 2018

Spreadsheets, statistics, mathematics and computational thinking

We need to teach all our students how to design, create, test, debug and use spreadsheets. We need to teach this integrated with mathematics, statistics and computational thinking. Spreadsheets can be a valuable tool in many other subject areas including biology, physics, history and geography, thus facilitating integrated learning experiences. Spreadsheets are versatile and ubiquitous – and most have errors. A web search on “How many spreadsheets have errors?” gives alarming results. The commonly quoted figure is 88%. These spreadsheets with errors are not just little home spreadsheets for cataloguing your Lego collection or planning your next vacation. These spreadsheets […]
24 April 2017

Graphs – beauty and truth

Graphs – beauty and truth (with apologies to Keats) A good graph is elegant I really like graphs. I like the way graphs turn numbers into pictures. A good graph is elegant. It uses a few well-placed lines to communicate what would take a paragraph of text. And like a good piece of literature or art, a good graph continues to give, beyond the first reading. I love looking at my YouTube and WordPress graphs. These graphs tell me stories. The WordPress analytics tell me that when I put up a new post, I get more hits, but that everyday […]
9 May 2016

There's more to reading graphs than meets the eye

There’s more to reading graphs than meets the eye For those of us who know how to read a graph, it can be difficult to imagine what another person could find difficult. But then when I am presented with an unusual style of graph, or one where the data has been presented badly, I suddenly feel empathy for those who are less graph-literate. Graphs are more common now as we have Excel to make them for us – for better or worse. An important skill for the citizens of tomorrow and today is to be able to read a graph […]
5 October 2015

Summarising with Box and Whisker plots

In the Northern Hemisphere, it is the start of the school year, and thousands of eager students are beginning their study of statistics. I know this because this is the time of year when lots of people watch my video, Types of Data. On 23rd August the hits on the video bounced up out of their holiday slumber, just as they do every year. They gradually dwindle away until the end of January when they have a second jump in popularity, I suspect at the start of the second semester. One of the first topics in many statistics courses is summary […]
23 April 2014

A helpful structure for analysing graphs

Mathematicians teaching English “I became a maths teacher so I wouldn’t have to mark essays” “I’m having trouble getting the students to write down their own ideas” “When I give them templates I feel as if it’s spoon-feeding them” These are comments I hear as I visit mathematics teachers who are teaching the new statistics curriculum in New Zealand. They have a point. It is difficult for a mathematics teacher to teach in a different style. But – it can also be rewarding and interesting, and you never get asked, “Where is this useful?” The statistical enquiry cycle provides a […]
24 June 2013

Difficult concepts in statistics

Recently someone asked: “I don’t suppose you’d like to blog a little on the pedagogical knowledge relevant to statistics teaching, would you? A ‘top five statistics student misconceptions (and what to do about them)’ would be kind of a nice thing to see …” I wish it were that easy. Here goes: Things that I have found students find difficult to understand and what I have done about them. Observations When I taught second year regression we would get students to collect data and fit their own multiple regressions. The interesting thing was that quite often students would collect unrelated […]
25 February 2013

Interpreting Scatterplots

Patterns, vocab and practice, practice, practice An important part of statistical analysis is being able to look at graphical representation of data, extract  meaning and make comments about it, particularly related to the context. Graph interpretation is a difficult skill to teach as there is no clear algorithm, such as mathematics teachers are used to teaching, and the answers are far from clear-cut. This post is about the challenges of teaching scatterplot interpretation, with some suggestions. When undertaking an investigation of bivariate measurement data, a scatterplot is the graph to use. On a scatterplot we can see what shape the […]
20 February 2013

Statistical Story-telling with time series data

Statistics is about story-telling. For people who understand them, graphs tell a story. To the initiated, even a p-value, and some summary statistics can help to tell a story. Part of the role of a statistician is to extract the story from the data. The role of a statistics teacher is to enable students first to recognise that there is a story, then to enable them to tell the story through the tools of analysis and communication. This idea of statistics as story-telling is explained in an award-winning paper byPfannkuch, Regan, Wild and Horton,Telling Data Stories: Essential Dialogues for Comparative […]
11 February 2013

Excel, SPSS, Minitab or R?

I often hear this question: Should I use Excel to teach my class? Or should I use R? Which package is the best? Update in April 2018: I have written a further post, covering other aspects and other packages. It depends on the class The short answer is: It depends on your class. You have to ask yourself, what are the attitudes, skills and knowledge that you wish the students to gain in the course. What is it that you want them to feel and do and understand? If the students are never likely to do any more statistics, what […]
12 November 2012

Beware of Excel Histograms

Excel histograms are a disgrace. Microsoft should be embarrassed to have them associated with their ubiquitous and generally wonderful spreadsheet, Excel. I have previously posted on how useful and versatile Excel is for enabling people to bypass the number crunching, and get to the ideas behind statistics. This is mostly true. But the histogram add-in should come with a health and safety warning. To start with, the default look for the histogram is outrageously poor. I have some data on times a person takes to solve a Rogo puzzle. (Collected as part of our research on what factors affect solution […]