Posts filed under Education (86)

February 12, 2012

More on telly viewing statistics ….

Media 7 last week featured our very own mistress of stats, Rachel Cunliffe, discussing why you can’t take a monthly cumulative audience and divide by four to get the weekly cumulative audience.

Media 7 host Russell Brown, in his latest Public Address column, looks at how a distinctly dodgy ‘statistic’ that came out of former broadcasting minister Jonathan Coleman’s office to justify Cabinet’s decision not to renew TVNZ 7’s funding was perpetuated through the media …   a must-read.

February 8, 2012

Breakfast wars

“High carb breakfasts boost brain power”.  Now, why does that sound familiar.. Oh, yes.  Last month it was the Egg Foundation pushing “Eggs may increase alertness”. This time it’s the Glycemic Index Foundation.

As the school year gets under way, new research is adding further weight to evidence that breakfast is the most important meal of the day, especially for children.

Research published last June, so it’s hardly new for the new school year. And the research only studied children who regularly eat breakfast, so it can’t really be evidence that breakfast is the most important meal of the day, or say whether this is more true for children.

Research by three British institutions 

Author names? Journal names? Institution names?  I’ve seen at least five universities in Britain with my own eyes, and am reliably informed there are several more.

has shown a strong link  between low GI, higher carbohydrate breakfasts and better academic  performance.

We can allow “strong link” as mere puffery, but the research did not include any data whatsoever about academic performance

The study, which involved 60 students, found that a low GI,  higher carbohydrate breakfast helped students do maths tasks more  quickly and accurately, and improved attentiveness.

I suppose counting backwards from 100 by 7s just about qualifies as a maths task, even for teenagers, but it’s a bit of a stretch.

The Glycemic Index (GI) is a measure of how effective  carbohydrates – sugars and starches – are on blood glucose levels.

GI is a measure of how fast or slowly carbohydrates affect blood glucose levels.  Wikipedia has it much more clearly Carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream have a high GI; carbohydrates that break down more slowly, releasing glucose more gradually into the bloodstream, have a low GI.”

At least, by quoting Dr Alan Barclay, of the Glycemic Index Foundation, the story did make it possible to track down the real research. Dr Barclay’s blog has a link to the paper, which was published in the European Journal of Clinical Nutrition.   Unless you’re at a university, you will have to pay to read it, so I will summarise.

Of the 60 children recruited, 19 had a “High GL, low GI” breakfast. This meant they were in the lower half for GI and the upper half for glycemic load (total carbohydrates), not that their breakfasts were high or low GI on an absolute scale.  There were three other groups, from the three other combinations of high/low GI and  GL.

The children had seven cognitive function tests. Three of the seven didn’t show any differences between the breakfast groups. For the other four tests the results were mixed:

Specifically, high-GI was associated with better immediate recall (short-term memory), high-GL with better matrices performance (inductive reasoning), and low-GI and high-GL with better speed of information processing (vigilance, sustained attention) and serial sevens performance (vigilance, working memory).

And this is before we start worrying about the correlation vs causation issue, the fact that the high-GL,low-GI breakfast averaged more total calories, or the fact that 13 of the 19 teenagers in the high-GL, low-GI group were girls.

December 31, 2011

Student multitasking

Another seasonal phenomenon at this time of year is the end of US college football. For those who haven’t encountered the game, American football is not entirely unlike rugby, only with less actual kicking and more ad breaks.

Some economists in Oregon have looked at the relationship between the average male:female GPA difference  at the University of Oregon and the performance of the Ducks, the University’s football team.

So what did the economists find? While the average GPA for male students was always lower than for female students, there was a definite pattern with a larger gap in years when the Ducks did well and a smaller gap when the team did poorly. (more…)

December 16, 2011

Freakonomics: what went wrong

Andrew Gelman and Kaiser Fung have an article in American Scientist

As the authors of statistics-themed books for general audiences, we can attest that Levitt and Dubner’s success is not easily attained. And as teachers of statistics, we recognize the challenge of creating interest in the subject without resorting to clichéd examples such as baseball averages, movie grosses and political polls. The other side of this challenge, though, is presenting ideas in interesting ways without oversimplifying them or misleading readers. We and others have noted a discouraging tendency in the Freakonomics body of work to present speculative or even erroneous claims with an air of certainty. Considering such problems yields useful lessons for those who wish to popularize statistical ideas.

August 8, 2011

Do lunar and indigenous fishing calendars actually work?

You’ll be able to find out on Tuesday August 16 at 4pm, when Department of Statistics masters student Ben Stevenson, who has been working under the supervision of Associate Professor Russell Millar, presents his findings into this very question. See more at http://www.stat.auckland.ac.nz/uoa/home/events/template/event_item.jsp?cid=411574

Student Ben Stevenson, left, and Associate Professor Russell Millar check out a freshly-caught snapper.

 

July 13, 2011

Making Data Meaningful Guides

Making Data Meaningful

The United Nations Economic Commission for Europe has been releasing a series of guides about communicating with statistics and part 3 is now out:

Communicating with the media (PDF) – a practical tool for producers of statistics find the best way to get their message across and to communicate effectively with the media.

The Making Data Meaningful guides are intended as a practical tool to help managers, statisticians and media relations officers in statistical organisations use text, tables, charts, maps and other devices to bring statistics to life for non-statisticians.

Earlier editions are below:

The thorough guides are excellent practical primers and the latest one features quite a bit of social media applications.

Thanks to our colleague Peter Davis for pointing out this resource set.