Stats Chat

Team Ratings for Week 10

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 44 matches played, 31 of which were correctly predicted, a success rate of 70.5%.
Here are the predictions for last week’s games.

Predictions for Week 10

Here are the predictions for Week 10. 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 7

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 48 matches played, 28 of which were correctly predicted, a success rate of 58.3%.
Here are the predictions for last week’s games.

Predictions for Round 7

Here are the predictions for Round 7. 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.

• Jessica Mackenzie on the “dire” wolf story, and how it got that way: “It’s important to consider how sausage like this is made, and I mean the stories—not the actual wolves.”
• Visualisation of the “demise of the love song” from pudding.cool
• Proportions and totals: is the individual risk of Alzheimer’s going down over time? (apparently, yes, even though the total number of cases goes up with the number of older people)
• Australian Associated Press fact check: Claim – 710,000 new voters on the electoral roll include migrants who arrived under Labor.  False: Migrants who arrived under Labor are not eligible to vote in the 2025 election.
• Stuff headline: Traffic ‘worse than Auckland’: Is this New Zealand’s most ‘anti-car’ city? We’re seeing proper use of headline single quotes here — ‘worse than Auckland’ is an attributed quotation in the text. It is, however, attributed to a single motorist.  Headlines about traffic density/slowness really shouldn’t just be one person’s opinion — traffic is measurable, and measured.

The International Statistical Institute is a professional organisation of statisticians. Its membership includes quite a lot of expertise on the production and use of official statistics, and it has a habit of commenting on political interference with official statistics.

The ISI has a statement on US official statistics

The International Statistical Institute (ISI) is concerned about government interference in the compilation and availability of Federal Statistics in the United States of America (USA). A proposed change in measuring and reporting U.S. Gross Domestic Product (GDP) serves as an important and timely example.

The statement goes on to explain that the USA has proposed removing government expenditures from GDP, and that this is both intrinsically a bad idea and also a weakening of international agreements on which official statistics to measure and how to define them.

[Disclaimer: I’m a member of the ISI, but I wasn’t involved in any way in producing this statement]

Team Ratings for Week 9

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 39 matches played, 29 of which were correctly predicted, a success rate of 74.4%.
Here are the predictions for last week’s games.

Predictions for Week 9

Here are the predictions for Week 9. 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 6

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 40 matches played, 22 of which were correctly predicted, a success rate of 55%.
Here are the predictions for last week’s games.

Predictions for Round 6

Here are the predictions for Round 6. 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 Week 6

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 35 matches played, 25 of which were correctly predicted, a success rate of 71.4%.
Here are the predictions for last week’s games.

Predictions for Week 6

Here are the predictions for Week 6. 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.

• Coffee nerd James Hoffman has a good video on an issue that crops up a lot on StatsChat — totals vs means/rates — though in his case it’s about shorter vs longer espresso shots for making flat white/cappucino.
• From Axios: foreigners don’t seem to be visiting the US as much — this is more interesting than it sounds, since a lot of the dip must be short-notice cancellations, which are relatively difficult/expensive.
  
• According to the NZ Herald, Elon Musk wants zero tariffs between the US and Europe. The story doesn’t point out that was very close to the situation a week ago (eg, according to economist Justin Wolfers.)
• Friday’s rain pushed the Auckland dam water levels up nearly four percentage points (conveniently, the total storage is close to 100 GL, so 1 GL is about 1 percentage point), which was bit more than a third of the deficit from average.  While we’re being nitpicky, that should be 9.99% below, not “-9.99% below”
  
• New York has a new subway map
  

Tim Welch has produced a nice Auckland Cycleways Dashboard (it’s a draft at the moment, or ‘beta’ as we nerds say).

Here are some of the University-relevant routes (click to embiggen, as usual)

These are based on the Auckland Transport cycle counters, which are good for the city centre and major bike paths, but less informative for, say, people commuting in from the south, where there aren’t bike lanes or bike counters.

The tariffs announced by President Trump are based on what he describes as tariffs imposed by other countries on the US. These don’t bear any obvious relationship to the numbers that ordinary economists would describe as tariffs

However, a poster on Twitter, @nonagonono, found there is a strong relationship between the claimed tariff and the countries import/export balance with the US

We want to be a little sceptical of relationships that come just from data-dredging, with no real theory, but this relationship is tight enough that it probably isn’t just a coincidence, and probably does tell us something about the definition of ‘tariff’ the President is using.  If so, the ‘tariff’ of 20% that New Zealand allegedly imposes is actually a trade deficit of 20%, which is not quite what I get from NZ trade figures (24%) but is close enough that some slight changes in definition might explain it.