Stats Chat

• The Guardian on spotting dodgy political statistics

• Pie are square: an experimental study finding square ‘pie’ charts better than round ones

• The difficulties of getting published papers corrected in science: New York Magazine on ‘psychoticism’ and political views

• How to draw a good map of droughts (severity/frequency)

• Are the political betting markets too stable?

• Lovely rant about Aloe vera gel and sunburn: “Listen, you antiscience monster: These people who sell aloe vera are stealing from you. As of 2004, the market for finished aloe products was worth $110 billion. The aloe barons are taking your money and building gigantic aloe palaces and not helping your sunburn at all. They are probably taking long soaks in great big hot tubs for which you helped pay. And they’re probably wearing lots of sunscreen, too, because they know nothing in their cabinets can heal sunburn.”

• When is AI (data mining/machine learning/etc) appropriate? from mathbabe.org

Each week, we would like to invite readers of Stats Chat to submit nominations for our Stat of the Week competition and be in with the chance to win an iTunes voucher.

Here’s how it works:

• Anyone may add a comment on this post to nominate their Stat of the Week candidate before midday Friday July 22 2016.
• Statistics can be bad, exemplary or fascinating.
• The statistic must be in the NZ media during the period of July 16 – 22 2016 inclusive.
• Quote the statistic, when and where it was published and tell us why it should be our Stat of the Week.

Next Monday at midday we’ll announce the winner of this week’s Stat of the Week competition, and start a new one.

(more…)

Team Ratings for Round 17

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Performance So Far

So far there have been 126 matches played, 93 of which were correctly predicted, a success rate of 73.8%.
Here are the predictions for last week’s games.

Predictions for Round 17

Here are the predictions for Round 17. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Team Ratings for Round 19

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Performance So Far

So far there have been 130 matches played, 80 of which were correctly predicted, a success rate of 61.5%.
Here are the predictions for last week’s games.

Predictions for Round 19

Here are the predictions for Round 19. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Each week, we would like to invite readers of Stats Chat to submit nominations for our Stat of the Week competition and be in with the chance to win an iTunes voucher.

Here’s how it works:

• Anyone may add a comment on this post to nominate their Stat of the Week candidate before midday Friday July 15 2016.
• Statistics can be bad, exemplary or fascinating.
• The statistic must be in the NZ media during the period of July 9 – 15 2016 inclusive.
• Quote the statistic, when and where it was published and tell us why it should be our Stat of the Week.

Next Monday at midday we’ll announce the winner of this week’s Stat of the Week competition, and start a new one.

(more…)

Team Ratings for Round 16

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Performance So Far

So far there have been 117 matches played, 86 of which were correctly predicted, a success rate of 73.5%.
Here are the predictions for last week’s games.

Predictions for Round 16

Here are the predictions for Round 16. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Team Ratings for Round 18

The basic method is described on my Department home page.

Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Performance So Far

So far there have been 126 matches played, 77 of which were correctly predicted, a success rate of 61.1%.
Here are the predictions for last week’s games.

Predictions for Round 18

Here are the predictions for Round 18. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

There’s a piece in the Herald, from The Conversation (with attribution, and links intact, yay!), on the supposed brain benefits of running.  There’s an interesting evolutionary speculation that humans, specifically, might benefit from running because of our pre-history of long-distance running to hunt

The growth of new brain cells in the hippocampus and the enhancement of spatial memory that is brought on by endurance running is basically an evolutionary safety net for when you have outrun your knowledge, when you have run so far that you no longer know where you are and you need to learn, fast. It is a mechanism that makes information uptake easiest when historically you might have been tired, lost, and at your most vulnerable.

There’s also some actual evidence on brain cell growth

What the new research tells us is that it is not just any exercise that will create new brain cells for you. In the study by Finnish researchers, they discovered that only certain kinds of exercise are likely to result in the growth of new brain cells in adults.

As you will find if you follow the link (but not from reading the story), that research is in rats. Unless their ancestors, too, pursued their prey across miles of African savannah, it rather tends to undermine the evolutionary argument.

Each week, we would like to invite readers of Stats Chat to submit nominations for our Stat of the Week competition and be in with the chance to win an iTunes voucher.

Here’s how it works:

• Anyone may add a comment on this post to nominate their Stat of the Week candidate before midday Friday July 8 2016.
• Statistics can be bad, exemplary or fascinating.
• The statistic must be in the NZ media during the period of July 2 – 8 2016 inclusive.
• Quote the statistic, when and where it was published and tell us why it should be our Stat of the Week.

Next Monday at midday we’ll announce the winner of this week’s Stat of the Week competition, and start a new one.

(more…)

• The ‘Questions and Answers’ link for the NZ Garden Bird Survey is a great example of how to think about experimental design and sources of variation
• How to win an election: how UK political parties’ expenditure varied by electorate in the last election, from the Monkey Cage blog at Washington Post, and an interesting discussion by Alex Harrowell at Yorkshire Ranter.
• The ozone hole (remember the ozone hole?) is finally starting to go away — visualisations from the LA Times. At least we got the easy one right.
• David Spiegelhalter explains why he isn’t worried about a higher rate of brain tumours in more-educated people.
• Nate Silver’s forecasts for the US election have started
• fMRI analyses (those pretty brain-wave pictures) seem to have a rather higher rate of false positives than people though (see also, emotional reactions in dead salmon)