# practice

5 April 2018

## Statistical software for worried students

Statistical software for worried students: Appearances matter Let’s be honest. Most students of statistics are taking statistics because they have to. I asked my class of 100 business students who choose to take the quantitative methods course if they did not have to. Two hands went up. Face it – statistics is necessary but not often embraced. But actually it is worse than that. For many people statistics is the most dreaded course they are required to take. It can be the barrier to achieving their career goals as a psychologist, marketer or physician. (And it should be required for many other […]
20 January 2014

## The Myth of Random Sampling

I feel a slight quiver of trepidation as I begin this post – a little like the boy who pointed out that the emperor has  no clothes. Random sampling is a myth. Practical researchers know this and deal with it. Theoretical statisticians live in a theoretical world where random sampling is possible and ubiquitous – which is just as well really. But teachers of statistics live in a strange half-real-half-theoretical world, where no one likes to point out that real-life samples are seldom random. The problem in general In order for most inferential statistical conclusions to be valid, the sample […]
23 September 2013

## On-line learning and teaching resources

Twenty-first century Junior Woodchuck Guidebook I grew up reading Donald Duck comics. I love the Junior Woodchucks, and their Junior Woodchuck Guidebook. The Guidebook is a small paperback book, containing information on every conceivable subject, including geography, mythology, history, literature and the Rubaiyat of Omar Khayyam.  In our family, when we want to know something or check some piece of information, we talk about consulting the Junior Woodchuck Guidebook. (Imagine my joy when I discovered that a woodchuck is another name for a groundhog, the star of my favourite movie!) What we are referring to is the internet, the source […]
12 August 2013

## Teaching with School League tables

NCEA League tables in the newspaper My husband ran for cover this morning when he saw high school NCEA (National Certificates of Educational Achievement)  league tables in the Press. However, rather than rave at him yet again, I will grasp the opportunity to expound to a larger audience. Much as I loathe and despise league tables, they are a great opportunity to teach students to explore data rich reports with a critical and educated eye.  There are many lessons to learn from league tables. With good teaching we can help dispell some of the myths the league tables promulgate. When […]
5 August 2013

## Parts and whole

The whole may be greater than the sum of the parts, but the whole still needs those parts. A reflective teacher will think carefully about when to concentrate on the whole, and when on the parts. Golf If you were teaching someone golf, you wouldn’t spend days on a driving range, never going out on a course. Your student would not get the idea of what the game is, or why they need to be able to drive straight and to a desired length. Nor would it be much fun! Similarly if the person only played games of golf it […]
8 July 2013

## Oh Ordinal data, what do we do with you?

What can you do with ordinal data? Or more to the point, what shouldn’t you do with ordinal data? First of all, let’s look at what ordinal data is. It is usual in statistics and other sciences to classify types of data in a number of ways. In 1946, Stanley Smith Stevens suggested a theory of levels of measurement, in which all measurements are classified into four categories, Nominal, Ordinal, Interval and Ratio. This categorisation is used extensively, and I have a popular video explaining them. (Though I group Interval and Ratio together as there is not much difference in […]
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 […]
10 June 2013

## The flipped classroom

Back in the mid1980s I was a trainee teacher at a high school in Rotorua. My associate teacher commented that she didn’t like to give homework much of the time as the students tended to practise things wrong, thus entrenching bad habits away from her watchful gaze. She had  a very good point! Bad habits can easily be developed when practising solving equations, trigonometry, geometry. Recently the idea of the “flipped classroom” has gained traction, particularly enabled by near universal access to internet technology in some schools or neighbourhoods. When one “flips” the classroom, the students spend their homework time […]
25 March 2013

## Less is more

“Less is More” is a bit of a funny title for a mathematical blog! Garlic bread and Ice Cream Sundaes Back in the seventies, garlic bread became very popular in our household. I loved its buttery, salty, garlicky goodness, and made it quite often. One time I decided that if a little bit of garlic was yummy, then lots of garlic would be even more delicious. I was wrong! The garlic bread was barely edible, and the house and its occupants gave off a distinctive aroma for several days. More garlic did not mean “better”. From then on whenever I […]
1 October 2012

## Statistical muscle memory

I am forever grateful to the teachers at my convent high school. In my first year I was required to take thirteen different subjects, one of which was typing. At the time computers were still objects mainly occurring in science fiction and operated by punch-cards, but the nuns thought we should get a wide exposure to different subjects (just in case I decided to be a typist/linguist/artist/scientist… instead of a maths teacher). Consequently I can touch-type, a skill which has been invaluable in my career as an academic. I don’t think about where my fingers are going – in fact […]