Posts written by Thomas Lumley (2645)

Today, Stuff’s “Well and Good” section has

There’s nothing wrong with the content, which describes some interesting dry sparkling wines one might want to try (if one liked that sort of thing enough to spend that much).  But it’s not a health story.

The very-low-sugar wines differ from ordinary ‘brut’ champagne by less than 10 grams of sugar per litre, in a drink that has more than 120 grams of alcohol per litre.   The sugar in an ordinary ‘brut’ bubbly is maybe 5% of the calorie content.

Not everything has to be about health.

From the New York Daily News: Study finds gin and tonic drinkers are more likely to be psychopaths, sadists

That’s not quite what the study finds. A slightly revised version is a couple of paragraphs into the story (credit for linking, but with a penalty for not mentioning it’s from 2015)

Researchers at Innsbruck University found that people who enjoy bitter flavors like the tonic water in a gin and tonic, black coffee, and dark chocolate are more prone to “Machiavellianism, psychoticism, and narcissism,” among other traits.

Here’s the list of ‘bitter’ flavoured foods they used (from)

Providing enough oxygen in a year for 132 people to breathe for a day could be more simply expressed as providing about one-third of the oxygen needed by one person.

Q: Did you see that drinking Champagne every day can prevent dementia?

A: Didn’t that story come out a while ago?

Q: June, I think. But it’s more relevant now. And it’s going to be 38C today, so it’s not like you have anything better to do. And Champagne is seasonal at the moment.

A: Ok, ok.  I’ll look it up

A: Here’s the press release

Q: That’s dated 2013. Are you sure it’s the right one?

A: It was linked from one of the stories you gave me.

Q: And you found the research paper?

A: Yes. That’s also from 2013

Q: It’s in a journal called Antioxidants and Redox Signalling? That doesn’t really sound like a medical journal about dementia.

A: No, it doesn’t.

Q: How many people were in the study?

A: None

Q: Ok, how many mice?

A: 8 elderly rats in each of three treatment groups: control, alcohol, Champagne.

Q: And the Champagne rats were less likely to get dementia?

A: No, they did slightly better on tests involving remembering whether they’d found a food pellet in the left or right tunnel of a maze.

Q: How long were they given Champagne diet?

A: Six weeks.

Q: But it was real Champagne

A: Yes — the researchers think that because Champagne is made partly with red-wine grapes such as Pinot Noir it will contain beneficial compounds similar to those in red wine

Q: But doesn’t red wine also contain compounds similar to those in red wine?

A: Indeed. You could just drink the Pinot Noir straight.

Q: Three glasses a day seems quite a lot, especially for a rat.

A: That’s scaled by body weight: 1.78 ml/kg

Q: And do rat doses usually scale that way to humans?

A: No, if you use a more standard formula you end up with about 1.3 glasses per week as the equivalent dose in people.

Q: Not such a good headline

A: No

Q: We’d know if 1-2 glasses of red wine per week prevented dementia, wouldn’t we?

A: Yes, probably. The usual message applies: if you’re drinking champagne primarily for the health benefits, you’re doing it wrong.

Now, in a sense this doesn’t matter. Since it’s a bogus clicky poll on a Donald Trump campaign site, it’s not there for data collection.

But that’s still an impressive piece of not trying to look as though you care.

(via @alittlestats)

The University is closed until after the New Year, so this is the StatsChat silly season.

To start with, a quiz question:

What is unusual and StatsChat-relevant about this molecule?

From the New York Times, in what’s otherwise a really interesting story

The prospectors had unearthed what would come to be called the Patricia Emerald: a dazzling 12-sided crystal roughly the size of a soup can, with a weight of 632 carats — more than a quarter of a pound

If you have a rock `roughly the size of a soup can’ it’s going to weigh more than a soup can roughly the size of a soup can. A standard US can of soup has volume 10 fluid oz, and weighs over half a pound.  The Patricia Emerald is more the size of one of those small coconut cream cans — which, to be fair, is seriously impressive for an emerald.

Q: Did you see there’s a diet that makes you burn energy ten times faster?

A: That … doesn’t sound very likely.

Q: It’s in the Herald

A: But it’s also in the Daily Mail.

Q: You could look up the research paper

A: <sigh>

A: Ok. Here it is.

Q: That took a while.

A: The story didn’t give the names of any of the researchers.

Q: Did the diet make people burn energy ten times faster?

A: No

Q: Mice?

A: It was people, but they didn’t burn energy ten times faster

Q: Are you sure?

A: Here’s the graph from the research paper: RMR stands for ‘resting metabolic rate’ and the colors indicate the groups

Q: The red line is higher.  Is that the magic diet?

A: Yes.

Q: It’s not ten times higher

A: No

Q: Ten what, then?

A: The slope of the red line is ten times as steep as the slope of the other lines

Q: They all look kinda flat to me.

A: What’s ten times not a lot?

Q: Ok. Point.  The red line looks higher right from the start. The story says “They were randomly placed into three groups”

A: … “in the order they signed up for the study.”

Q: Well, you can’t randomly assign them before they sign up. Oh.  You mean they were just allocated to each group in turn.

A: Yes.

Q: Is that international best practice?

A: No.

Q: But does the diet work?

A: I don’t think the research adds much to what’s known about this question

Q: Which is?

A: Do you really think you’re going to get a simple and definitive solution to the low-carb diet controversy from a statistical blog?

Q: Ok, can I at least have some sort of sound bite?

A: Magic diet is not magic

In the US, the Federal Communications Commission was collecting public comments about ‘net neutrality’ — an issue that’s commercially and politically sensitive in a country where many people don’t have any real choice about their internet provider.

There were lots of comments: from experts, from concerned citizens, from people who’d watched a John Oliver show. And from bots faking real names and addresses on to automated comments.   The Wall Street Journal contacted a random sample of nearly 3000 commenters and found the majority of those they could get in contact with had not submitted the comment attached to their details.  The StartupPolicyLab attempted to contact 450,000 submitters, and got a response from just over 8000. Of the 7000 contacted about pro-neutrality comments, nearly all agreed they had made the comment, but of the 1000 responses about anti-neutrality comments, about 88% said they had not made the comment.

It’s obviously a bad idea to treat the comments as a vote. Even if the comments were from real US people, with one comment each, you’d need to do some sort of modelling of the vast majority who didn’t comment.  But what are they good for?

One real benefit is for people to provide ideas you hadn’t thought of.  The public comment process on proposed New Zealand legislation certainly allows for people like Graeme Edgeler to point out bugs in the drafting, and for people whose viewpoints were not considered to speak out.  For this, it doesn’t matter what the numbers of comments are, for and against. In fact, it helps if people who don’t have something to say don’t say it.

With both petitions and public comments there’s also some quantitative value in showing that concern about some issue you weren’t worrying about isn’t negligibly small; that thousands (in NZ) or hundreds of thousands (in the US) care about it.

But if it’s already established that an issue is important and controversial, and you care about the actual balance of public opinion, you should be doing a proper opinion poll.