Posts filed under General (2813)

March 19, 2025

Super Rugby Predictions for Week 6

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.

Current Rating Rating at Season Start Difference
Blues 13.23 14.92 -1.70
Chiefs 12.20 11.43 0.80
Crusaders 9.39 8.99 0.40
Hurricanes 8.24 10.97 -2.70
Brumbies 5.49 6.19 -0.70
Reds 1.54 1.35 0.20
Highlanders -1.60 -2.50 0.90
Waratahs -4.92 -5.17 0.30
Fijian Drua -6.18 -7.98 1.80
Western Force -6.92 -6.41 -0.50
Moana Pasifika -9.93 -11.25 1.30

 

Performance So Far

So far there have been 25 matches played, 19 of which were correctly predicted, a success rate of 76%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Highlanders vs. Hurricanes Mar 14 18 – 20 -7.00 TRUE
2 Brumbies vs. Fijian Drua Mar 14 38 – 21 14.90 TRUE
3 Crusaders vs. Western Force Mar 15 55 – 33 20.00 TRUE
4 Chiefs vs. Blues Mar 15 32 – 31 2.70 TRUE
5 Reds vs. Waratahs Mar 15 35 – 15 9.00 TRUE

 

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.

Game Date Winner Prediction
1 Moana Pasifika vs. Chiefs Mar 21 Chiefs -18.60
2 Highlanders vs. Reds Mar 22 Highlanders 0.90
3 Blues vs. Crusaders Mar 22 Blues 7.30
4 Waratahs vs. Brumbies Mar 22 Brumbies -6.90
5 Western Force vs. Fijian Drua Mar 23 Western Force 2.80

 

NRL Predictions for Round 3

Team Ratings for Round 3

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.

Current Rating Rating at Season Start Difference
Storm 10.26 9.29 1.00
Panthers 8.12 8.50 -0.40
Roosters 6.25 7.44 -1.20
Sharks 5.94 5.10 0.80
Sea Eagles 3.13 2.97 0.20
Cowboys 1.91 4.11 -2.20
Bulldogs 0.81 0.07 0.70
Knights 0.10 -0.05 0.10
Broncos -0.53 -1.82 1.30
Warriors -1.70 -1.68 -0.00
Raiders -2.11 -3.61 1.50
Dolphins -2.55 -1.96 -0.60
Rabbitohs -3.97 -4.35 0.40
Dragons -5.17 -4.55 -0.60
Eels -5.39 -3.02 -2.40
Titans -5.88 -5.50 -0.40
Wests Tigers -9.24 -10.97 1.70

 

Performance So Far

So far there have been 16 matches played, 9 of which were correctly predicted, a success rate of 56.2%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Knights vs. Dolphins Mar 13 26 – 12 4.70 TRUE
2 Warriors vs. Sea Eagles Mar 14 36 – 16 -3.30 FALSE
3 Panthers vs. Roosters Mar 14 32 – 38 6.00 FALSE
4 Dragons vs. Rabbitohs Mar 15 24 – 25 2.30 FALSE
5 Cowboys vs. Sharks Mar 15 12 – 36 1.10 FALSE
6 Raiders vs. Broncos Mar 15 32 – 22 0.40 TRUE
7 Eels vs. Wests Tigers Mar 16 6 – 32 9.60 FALSE
8 Bulldogs vs. Titans Mar 16 40 – 24 8.90 TRUE

 

Predictions for Round 3

Here are the predictions for Round 3. 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.

Game Date Winner Prediction
1 Storm vs. Panthers Mar 20 Storm 5.10
2 Warriors vs. Roosters Mar 21 Roosters -4.40
3 Broncos vs. Cowboys Mar 21 Broncos 0.60
4 Sharks vs. Rabbitohs Mar 22 Sharks 12.90
5 Dolphins vs. Wests Tigers Mar 22 Dolphins 9.70
6 Titans vs. Knights Mar 22 Knights -3.00
7 Eels vs. Bulldogs Mar 23 Bulldogs -3.20
8 Sea Eagles vs. Raiders Mar 23 Sea Eagles 8.20

 

AFL Predictions for Week 3

Team Ratings for Week 3

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.

Current Rating Rating at Season Start Difference
Hawthorn Hawks 26.00 21.95 4.00
Brisbane Lions 22.59 22.65 -0.10
Geelong Cats 18.82 15.04 3.80
Western Bulldogs 15.48 18.20 -2.70
Collingwood 11.79 5.39 6.40
GWS Giants 8.43 9.08 -0.70
Sydney Swans 7.23 12.60 -5.40
Adelaide Crows 6.04 2.69 3.30
Port Adelaide Power 2.61 7.63 -5.00
Fremantle Dockers 2.21 5.99 -3.80
Carlton Blues 1.73 5.01 -3.30
Melbourne Demons -0.94 -0.21 -0.70
Gold Coast Suns -1.98 -6.41 4.40
St Kilda Saints -2.46 0.89 -3.30
Essendon Bombers -8.76 -10.15 1.40
Richmond Tigers -27.72 -31.00 3.30
North Melbourne -34.37 -37.08 2.70
West Coast Eagles -39.10 -34.67 -4.40

 

Performance So Far

So far there have been 11 matches played, 7 of which were correctly predicted, a success rate of 63.6%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Richmond Tigers vs. Carlton Blues Mar 13 82 – 69 -36.00 FALSE
2 Hawthorn Hawks vs. Essendon Bombers Mar 14 111 – 85 37.50 TRUE
3 Geelong Cats vs. Fremantle Dockers Mar 15 147 – 69 20.00 TRUE
4 Sydney Swans vs. Brisbane Lions Mar 15 82 – 86 -4.50 TRUE
5 Collingwood vs. Port Adelaide Power Mar 15 136 – 45 10.10 TRUE
6 Western Bulldogs vs. North Melbourne Mar 15 113 – 97 55.30 TRUE
7 Adelaide Crows vs. St Kilda Saints Mar 16 135 – 72 12.80 TRUE
8 Melbourne Demons vs. GWS Giants Mar 16 74 – 77 3.10 FALSE
9 West Coast Eagles vs. Gold Coast Suns Mar 16 49 – 136 -17.30 TRUE

 

Predictions for Week 3

Here are the predictions for Week 3. 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.

Game Date Winner Prediction
1 Carlton Blues vs. Hawthorn Hawks Mar 20 Hawthorn Hawks -24.30
2 Western Bulldogs vs. Collingwood Mar 21 Western Bulldogs 3.70
3 Essendon Bombers vs. Adelaide Crows Mar 22 Adelaide Crows -3.80
4 Port Adelaide Power vs. Richmond Tigers Mar 22 Port Adelaide Power 41.30
5 St Kilda Saints vs. Geelong Cats Mar 22 Geelong Cats -10.30
6 Brisbane Lions vs. West Coast Eagles Mar 23 Brisbane Lions 72.70
7 North Melbourne vs. Melbourne Demons Mar 23 Melbourne Demons -33.40
8 Fremantle Dockers vs. Sydney Swans Mar 23 Fremantle Dockers 6.00

 

March 18, 2025

Good news graph

The Washington Post writes about cervical cancer: the vaccine works.  This isn’t new news: we know the vaccine stops infection with cancer-causing strains of the human papillomavirus (that’s why it was approved). We know the vaccine stops cervical cancer: the first reliable data came out a few years ago.  Now the first cohort of vaccinated girls is old enough that we’re seeing the reduction in cervical cancer deaths.

Using data from the National Center for Health Statistics, researchers looked at cervical cancer deaths in three-year blocks of time. Between 1992 and 2021, there were 398 cervical cancer deaths reported among women younger than 25. During the period of 1992-1994 to 2013-2015, mortality from cervical cancer gradually declined 3.7 percent each year. The period of 2013-2015 to 2019-2021 saw an even greater drop to 15.2 percent annually, according to the study.

The number of deaths decreased from 55 in 1992-1994 to 35 in 2013-2015 to 13 in 2019-2021.

“Assuming that the trend from 1992-1994 to 2013-2015 would have continued, an estimated 26 additional cervical cancer deaths would have been expected to occur between 2016 to 2021, based on projected mortality rates,” the authors wrote.

That description seems like a hard way to present this graph from the article in JAMA (perhaps copyright is the problem?)

The squares are what happened in reality. The orange line shows the downward trend we were seeing before the vaccine, due to better testing and treatment.  As you can see, the last two squares, post-vaccine, are dramatically below the orange line. Below is good.

March 14, 2025

Denominators

Earlier this week, Wikipedia’s front-page “Did you know…” section this week referenced the year that Vatican City had the world’s highest murder rate. In 1998, a double homicide in the Swiss Guards put the murder rate over 200 per 100,000 inhabitants, more than twice the rate in any of the Caribbean countries that usually head the list and roughly infinity times the usual rate in recent years when it has been a separate country. That’s a real rate, with the right denominator, it’s just that the year to year variability makes rates a relatively unhelpful summary.

Vatican City has a denominator problem for minor crimes; in 1992 there were 392 ‘civil offences’ and 608 ‘penal offences’, working out to a bit less than 100% and a bit more than 100% of the number in resident population.  The problem is that the tiny state has many millions of  visitors per year and they, rather than the resident population, are both the perpetrators and victims of the minor crimes.  The resident population isn’t the right denominator.

A less dramatic version of this problem showed up when looking at rates of violent crime in parts of central Wellington some years back.

March 12, 2025

More Panadol scare headlines

The New York Post is saying

Attention-deficit/hyperactivity disorder is a common behavioral condition that affects approximately 7 million US children, including about a million kids diagnosed since 2016.

The reason for the recent rise in diagnoses is under debate — a new study in the journal Nature Mental Health suggests the culprit could be in your medicine cabinet.

They’re talking about paracetamol (or as Americans call it, acetaminophen).  There’s a new study that looks at a fairly small group of US mothers and kids and finds weak evidence of a correlation between ADHD diagnosis in the kid and use of paracetamol by the mother.   You might remember this topic from previous StatsChat episodes.  There was  originally a Danish study that was surprised to stumble across a correlation. A New Zealand study checking up on the correlation also found it.

A Spanish study resulted in the NZ Herald (from the Daily Mail) scare headline One paracetamol in pregnancy could raise risk of autism. This was especially egregious since not only did the study say nothing about ‘one paracetamol’ and wasn’t really about autism, it actually found lower rates of the symptoms in kids whose mothers took paracetamol. The study argued that while the rates were lower in those kids, they should have been even lower based on other risk factors.   At this point it was all plausible and maybe a bit concerning but not reason for major change in medical practice — after all, mothers aren’t taking Panadol for fun.

In 2023, a combination of most of the published studies estimated a slight increase in risk, about 25%.  On the other hand, A very big Swedish study, using data from everyone born in Sweden from 1995 to 2019, then found no suggestion of a correlation.

So what’s the point of this new study? Well, one of the issues in interpreting these correlation studies is that many of them didn’t know for sure who actually took paracetamol.  For normal people this would be a big issue — lots of medications include paracetamol, and you might easily miss some, or just forget. Pregnant women, though, tend not to just casually take cough syrup or whatever.  Even so, if you happened to have data lying around from blood samples which told you who had taken paracetamol, you might be interested in seeing what the correlation was like.   So they did. And the correlation was broadly similar to what the small, early studies had seen: kids whose mothers blood samples showed paracetamol were about twice as likely to have ADHD.  That’s nice to know, even if it’s not a big change in the evidence.

We still have the conflict between ‘no sign of a correlation’ in the big Swedish study and ‘about 25% higher’ in the combined smaller studies.  It’s possible that paracetamol has an effect and that the Swedish study missed it because it didn’t measure paracetamol use as accurately. It’s also possible that the reasons for taking paracetamol (eg illness, fever) are what causes ADHD. Or it could all be some sort of bias and the Swedish study could be correct. It’s hard to tell.  Ask your doctor, etc.

The new study, of course, does not suggest paracetamol is responsible for recent trends in ADHD diagnosis: that claim is down to the New York Post, and is pretty clearly wrong. Here’s the trend:

Paracetamol became popular as a relatively safe, over-the-counter treatment a long time ago now. It might have been response for an ADHD trend in, say,  the 1980s, but not a trend in the 21st century.

Briefly

  • The New York Times has an interactive with graphs showing how everything changed when Covid started.  It’s also an explanation of why it’s hard to estimate the effects of specific actions on Covid: everything changed at once
  • Visualising how different languages represent animal noises: the spellings can look very different, but the underlying phonetics are more similar
  • “The answer to the how-many-significant-digits problem is the same as the answer to the what-to-graph problem: The click-through solution“. Or in other words, you can have tables without stupid numbers of digits and let people who want detail click to see it
  • The website of the US Centers for Disease Control as it existed on Jan 6 has been copied to RestoredCDC.org, hosted in Europe.  This won’t help with ongoing data collection, but it does make the past data from the CDC more reliably available.
March 11, 2025

United Rugby Championship Predictions for Week 13

Team Ratings for Week 13

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.

Current Rating Rating at Season Start Difference
Leinster 13.75 12.09 1.70
Glasgow 8.10 9.39 -1.30
Bulls 7.44 8.83 -1.40
Munster 4.39 9.28 -4.90
Lions 4.35 6.73 -2.40
Stormers 4.23 6.75 -2.50
Sharks 1.78 -2.94 4.70
Edinburgh 1.54 0.09 1.50
Cheetahs 0.80 0.80 0.00
Ospreys -0.01 -2.51 2.50
Ulster -0.55 2.52 -3.10
Connacht -1.62 -0.76 -0.90
Scarlets -3.42 -10.65 7.20
Benetton -3.62 1.02 -4.60
Cardiff Rugby -5.70 -2.55 -3.10
Southern Kings -6.52 -6.52 0.00
Zebre -9.65 -16.17 6.50
Dragons -15.29 -15.41 0.10

 

Performance So Far

So far there have been 96 matches played, 69 of which were correctly predicted, a success rate of 71.9%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Sharks vs. Lions Mar 09 25 – 22 -0.90 FALSE

 

Predictions for Week 13

Here are the predictions for Week 13. 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.

Game Date Winner Prediction
1 Cardiff Rugby vs. Lions Mar 22 Lions -4.60
2 Glasgow vs. Munster Mar 22 Glasgow 9.20
3 Sharks vs. Zebre Mar 22 Sharks 16.90
4 Benetton vs. Edinburgh Mar 23 Benetton 0.30
5 Bulls vs. Leinster Mar 23 Leinster -0.80
6 Dragons vs. Ulster Mar 23 Ulster -9.20
7 Ospreys vs. Connacht Mar 23 Ospreys 7.10
8 Scarlets vs. Stormers Mar 23 Stormers -2.20

 

Super Rugby Predictions for Week 5

Team Ratings for Week 5

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.

Current Rating Rating at Season Start Difference
Blues 13.11 14.92 -1.80
Chiefs 12.32 11.43 0.90
Crusaders 9.25 8.99 0.30
Hurricanes 8.59 10.97 -2.40
Brumbies 5.34 6.19 -0.90
Reds 1.06 1.35 -0.30
Highlanders -1.95 -2.50 0.60
Waratahs -4.44 -5.17 0.70
Fijian Drua -6.03 -7.98 1.90
Western Force -6.78 -6.41 -0.40
Moana Pasifika -9.93 -11.25 1.30

 

Performance So Far

So far there have been 20 matches played, 14 of which were correctly predicted, a success rate of 70%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Blues vs. Brumbies Mar 07 20 – 21 12.90 FALSE
2 Fijian Drua vs. Chiefs Mar 08 28 – 24 -15.90 FALSE
3 Moana Pasifika vs. Hurricanes Mar 08 40 – 31 -16.90 FALSE
4 Waratahs vs. Western Force Mar 08 34 – 10 4.30 TRUE
5 Crusaders vs. Reds Mar 09 43 – 19 11.10 TRUE

 

Predictions for Week 5

Here are the predictions for Week 5. 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.

Game Date Winner Prediction
1 Highlanders vs. Hurricanes Mar 14 Hurricanes -7.00
2 Brumbies vs. Fijian Drua Mar 14 Brumbies 14.90
3 Crusaders vs. Western Force Mar 15 Crusaders 20.00
4 Chiefs vs. Blues Mar 15 Chiefs 2.70
5 Reds vs. Waratahs Mar 15 Reds 9.00

 

NRL Predictions for Round 2

Team Ratings for Round 2

Unfortunately my predictions for the first round were incorrect because I had the Dolphins playing at home, when in fact the Rabbitohs were at home. The results below use the correct home ground and show the Rabbitohs as predicted winners rather than the Dolphins.

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.

Current Rating Rating at Season Start Difference
Storm 10.26 9.29 1.00
Panthers 8.71 8.50 0.20
Roosters 5.66 7.44 -1.80
Sharks 4.89 5.10 -0.20
Sea Eagles 4.13 2.97 1.20
Cowboys 2.96 4.11 -1.20
Bulldogs 0.43 0.07 0.40
Broncos -0.04 -1.82 1.80
Knights -0.38 -0.05 -0.30
Dolphins -2.07 -1.96 -0.10
Raiders -2.59 -3.61 1.00
Warriors -2.69 -1.68 -1.00
Eels -3.99 -3.02 -1.00
Rabbitohs -4.23 -4.35 0.10
Dragons -4.90 -4.55 -0.30
Titans -5.50 -5.50 -0.00
Wests Tigers -10.64 -10.97 0.30

 

Performance So Far

So far there have been 8 matches played, 6 of which were correctly predicted, a success rate of 75%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Raiders vs. Warriors Mar 02 30 – 8 -1.90 FALSE
2 Panthers vs. Sharks Mar 02 28 – 22 3.40 TRUE
3 Roosters vs. Broncos Mar 06 14 – 50 12.30 FALSE
4 Wests Tigers vs. Knights Mar 07 8 – 10 -7.90 TRUE
5 Rabbitohs vs. Dolphins Mar 07 16 – 14 0.60 TRUE
6 Dragons vs. Bulldogs Mar 08 20 – 28 -1.60 TRUE
7 Sea Eagles vs. Cowboys Mar 08 42 – 12 1.90 TRUE
8 Storm vs. Eels Mar 09 56 – 18 15.30 TRUE

 

Predictions for Round 2

Here are the predictions for Round 2. 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.

Game Date Winner Prediction
1 Knights vs. Dolphins Mar 13 Knights 4.70
2 Warriors vs. Sea Eagles Mar 14 Sea Eagles -3.30
3 Panthers vs. Roosters Mar 14 Panthers 6.00
4 Dragons vs. Rabbitohs Mar 15 Dragons 2.30
5 Cowboys vs. Sharks Mar 15 Cowboys 1.10
6 Raiders vs. Broncos Mar 15 Raiders 0.40
7 Eels vs. Wests Tigers Mar 16 Eels 9.60
8 Bulldogs vs. Titans Mar 16 Bulldogs 8.90