Posts filed under General (1218)

August 8, 2017

Currie Cup Predictions for Round 4

Team Ratings for Round 4

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
Cheetahs 5.69 4.33 1.40
Lions 5.25 7.41 -2.20
Blue Bulls 2.94 2.32 0.60
Western Province 2.55 3.30 -0.70
Sharks 2.48 2.15 0.30
Pumas -10.24 -10.63 0.40
Griquas -11.42 -11.62 0.20

 

Performance So Far

So far there have been 9 matches played, 8 of which were correctly predicted, a success rate of 88.9%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Sharks vs. Griquas Aug 04 41 – 3 17.10 TRUE
2 Blue Bulls vs. Lions Aug 05 54 – 22 0.40 TRUE
3 Western Province vs. Pumas Aug 05 34 – 19 17.70 TRUE

 

Predictions for Round 4

Here are the predictions for Round 4. 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 Blue Bulls vs. Sharks Aug 09 Blue Bulls 5.00
2 Pumas vs. Cheetahs Aug 09 Cheetahs -11.40
3 Griquas vs. Western Province Aug 09 Western Province -9.50

 

August 7, 2017

Millennials and their pink wine

From Stuff, under  the headline Millennials love rose so much they’ve warped the traditional wine market

Millennials dominate Kiwi rose drinking, according to the report. Seventeen per cent of the still wine drunk by under-24s is rose . At 25-35 years it is about 11 per cent and at 35-44 years it drops to 6 per cent. 

Even if that’s true, younger people are less likely to be drinking wine than older people. Here are two graphs of the probability that the most recent alcoholic drink was wine, for women on the left and men on the right, by age groups (source).  The blue is under-24, then 25-44, 45-64, and 65+.

women-winemen-wine

A slightly larger proportion of the wine drunk by millennials is pink, but that’s not the same as saying they drink a large proportion of all the pink wine.

 

August 5, 2017

Just a temporary inconvenience

From Radio NZ

The book explores the widely held view that farm livestock are responsible for an enormous net production of new global warming gases.

“Once you take into account the entire cycle of the life of a cow, it’s actually impossible for the cow to omit even one extra atom of carbon to the atmosphere that wasn’t there already there, they are carbon neural in the end.” he says.

As you’d expect, there’s a sense in which this is completely true. It’s just not a sense that contradicts the standard views of methane and global warming.

What’s going on is easier to see if you consider carbon outputs from the other end of the cow.  Some of the carbon a cow takes in comes out as cowshit. This carbon doesn’t lie around for ever; it returns to the skies and the soil as part of the Great Circle of Life. Hakuna Matata. This doesn’t happen instantaneously, though. In the short term, you still need to wear sensible footwear or watch your step when you cross the field.

There’s an equilibrium between the production and decay of cowshit. When you increase the number of cows, the ambient cowshit level increases, and settles in at a new, higher equilibrium. When you decrease the number of cows, it decreases towards a new, lower equilibrium. The time this takes is governed by how long cowshit takes to decay, so it’s pretty fast.

In a similar, but more serious way, some of the carbon that goes into a cow comes out the front end as methane.  The methane doesn’t hang around in the air for ever; it turns back into carbon dioxide and water. As with cowshit, this doesn’t happen instantaneously.

There’s an equilibrium between the production and decay of methane. When you increase the number of cows, the ambient cow-derived methane level increases, and settles in at a new, higher equilibrium. When you decrease the number of cows, it decreases towards a new, lower equilibrium. The time this takes is governed by how long methane takes to decay: over each passing decade about half of it goes away.

Carbon emitted as methane, unlike carbon emitted in cowshit, is more than a local nuisance.  Per atom of carbon, methane has 24 times the greenhouse warming effect of CO2, and while it doesn’t last for ever, it lasts long enough to make an important contribution to climate change.  There’s more than twice as much methane in the atmosphere now as there was two centuries ago.

Cows are long-term carbon-neutral: that means reducing cow numbers (or finding ways to reduce their methane production) would, in mere decades, roll back the increases they’ve caused in an important greenhouse gas.

August 2, 2017

Briefly

  • Graphics: there’s a solar eclipse soon in the US. Washington Post‘s WonkBlog shows Google Trends search interest in iteclipse
  • Persuasive Cartography: 800 historical maps “intended primarily to influence opinions or beliefs – to send a message – rather than to communicate geographic information.”
  • Should there even be an app for this?”  and other tech questions from a workshop on design ethics. (Subquestion: should there be a prediction of this?)
  • “I never knew until very recently that the standard National Readership Survey socio-demographic classifications – ABC1, C2DE etc – deal with pensioners by classifying them all as working-class unless they are rich enough to be considered independently wealthy and therefore bucketed in with the As. ” Alex Harrowell on social class assessment and the politics of data
August 1, 2017

Super 18 Predictions for the Super Rugby Final

Team Ratings for the Super Rugby Final

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
Hurricanes 16.71 13.22 3.50
Crusaders 14.85 8.75 6.10
Lions 14.49 7.64 6.90
Highlanders 10.62 9.17 1.50
Chiefs 9.62 9.75 -0.10
Brumbies 1.81 3.83 -2.00
Stormers 1.38 1.51 -0.10
Sharks 0.72 0.42 0.30
Blues -0.22 -1.07 0.90
Waratahs -3.81 5.81 -9.60
Bulls -4.96 0.29 -5.20
Jaguares -5.03 -4.36 -0.70
Force -6.97 -9.45 2.50
Cheetahs -9.63 -7.36 -2.30
Reds -9.92 -10.28 0.40
Kings -12.08 -19.02 6.90
Rebels -15.29 -8.17 -7.10
Sunwolves -19.38 -17.76 -1.60

 

Performance So Far

So far there have been 141 matches played, 106 of which were correctly predicted, a success rate of 75.2%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Crusaders vs. Chiefs Jul 29 27 – 13 8.00 TRUE
2 Lions vs. Hurricanes Jul 29 44 – 29 -0.00 FALSE

 

Predictions for the Super Rugby Final

Here are the predictions for the Super Rugby Final. 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 Lions vs. Crusaders Aug 05 Lions 3.60

 

NRL Predictions for Round 22

Team Ratings for Round 22

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 9.57 8.49 1.10
Cowboys 5.79 6.90 -1.10
Sharks 4.27 5.84 -1.60
Broncos 3.76 4.36 -0.60
Raiders 2.92 9.94 -7.00
Panthers 2.58 6.08 -3.50
Roosters 2.27 -1.17 3.40
Eels 0.68 -0.81 1.50
Sea Eagles -1.33 -2.98 1.60
Dragons -1.45 -7.74 6.30
Rabbitohs -2.85 -1.82 -1.00
Warriors -3.32 -6.02 2.70
Titans -3.91 -0.98 -2.90
Wests Tigers -4.30 -3.89 -0.40
Bulldogs -5.42 -1.34 -4.10
Knights -11.30 -16.94 5.60

 

Performance So Far

So far there have been 152 matches played, 92 of which were correctly predicted, a success rate of 60.5%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Panthers vs. Bulldogs Jul 27 16 – 8 12.30 TRUE
2 Warriors vs. Sharks Jul 28 12 – 26 -1.60 TRUE
3 Eels vs. Broncos Jul 28 28 – 14 -2.10 FALSE
4 Knights vs. Dragons Jul 29 21 – 14 -8.80 FALSE
5 Rabbitohs vs. Raiders Jul 29 18 – 32 -0.10 TRUE
6 Roosters vs. Cowboys Jul 29 22 – 16 -1.20 FALSE
7 Storm vs. Sea Eagles Jul 30 40 – 6 10.80 TRUE
8 Titans vs. Wests Tigers Jul 30 4 – 26 8.50 FALSE

 

Predictions for Round 22

Here are the predictions for Round 22. 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 Bulldogs vs. Eels Aug 03 Eels -2.60
2 Dragons vs. Rabbitohs Aug 04 Dragons 4.90
3 Cowboys vs. Storm Aug 04 Storm -0.30
4 Knights vs. Warriors Aug 05 Warriors -4.00
5 Titans vs. Broncos Aug 05 Broncos -4.20
6 Sharks vs. Raiders Aug 05 Sharks 4.90
7 Sea Eagles vs. Roosters Aug 06 Roosters -0.10
8 Panthers vs. Wests Tigers Aug 06 Panthers 10.40

 

Currie Cup 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
Lions 6.15 7.41 -1.30
Cheetahs 5.69 4.33 1.40
Western Province 2.77 3.30 -0.50
Blue Bulls 2.05 2.32 -0.30
Sharks 1.80 2.15 -0.30
Pumas -10.45 -10.63 0.20
Griquas -10.75 -11.62 0.90

 

Performance So Far

So far there have been 6 matches played, 5 of which were correctly predicted, a success rate of 83.3%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Lions vs. Griquas Jul 28 48 – 43 22.60 TRUE
2 Sharks vs. Pumas Jul 29 29 – 0 15.80 TRUE
3 Cheetahs vs. Western Province Jul 30 30 – 17 6.40 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 Sharks vs. Griquas Aug 04 Sharks 17.10
2 Blue Bulls vs. Lions Aug 05 Blue Bulls 0.40
3 Western Province vs. Pumas Aug 05 Western Province 17.70

 

July 30, 2017

Coffee news?

In 2015, the Herald said

Drinking the caffeine equivalent of more than four espressos a day is harmful to health, especially for minors and pregnant women, the European Union food safety agency has said.

“It is the first time that the risks from caffeine from all dietary sources have been assessed at EU level,” the EFSA said, recommending that an adult’s daily caffeine intake remain below 400mg a day.

(I quoted it at the time: the link seems to be dead now).

Now we have, under the headline Good news for coffee lovers: Caffeine is harmless, says research

A review of 44 trials dispelled the widespread myth that caffeine, found in tea, coffee and fizzy drinks, is bad for the body.

It found that sticking to the recommended daily amount of 400mg – the equivalent four cups of coffee or eight cups of tea – has no lasting damage on the body.

The recommendation that 400mg/day is generally safe was described as ‘caffeine is dangerous’ in 2015 and ‘caffeine is harmless’ now.

Other not-news about this is the not-new research. Obviously the Daily Mail (the only link) isn’t a research source. The research was published in Complete Nutrition, a professional magazine for UK dieticians. As their website says

Each issue of CN is packed with articles which are practical, educational and topical, and all are written by independent, well-respected authors from across the profession.

That’s a valuable mission for a journal, but it would be surprising if an expert opinion article in a journal like that contained new research worth international headlines.

July 27, 2017

Will we ever use this in real life?

From deep in the archives at Language Log

The Pirahã language and culture seem to lack not only the words but also the concepts for numbers, using instead less precise terms like “small size”, “large size” and “collection”. And the Pirahã people themselves seem to be suprisingly uninterested in learning about numbers, and even actively resistant to doing so, despite the fact that in their frequent dealings with traders they have a practical need to evaluate and compare numerical expressions. A similar situation seems to obtain among some other groups in Amazonia, and a lack of indigenous words for numbers has been reported elsewhere in the world.

Many people find this hard to believe. These are simple and natural concepts, of great practical importance: how could rational people resist learning to understand and use them? I don’t know the answer. But I do know that we can investigate a strictly comparable case, equally puzzling to me, right here in the U.S. of A.

From context, you can probably guess where he’s heading

July 25, 2017

Tell them to buy an ad

From the editing blog “Heads Up”

… you don’t need a course in statistics to ask what a writer means by “incident count,” “city” and “occurrence percentage,” not to mention why and how the means are weighted, or even why users of an insurance comparison website would be a good representation of a city where a huge proportion of drivers are uninsured. 

And

This isn’t “fake news” in the 2016 sense; it’s the old-school kind that has always gotten past enough gatekeepers to do its work. The traditional response is “tell them to buy an ad.”