Posts filed under General (3156)

Q: Did you see “Cocaine now on tap in British homes” in the Herald

A: Yes.

Q: Is it true?

A: Not so as you’d notice.

Q: Didn’t they find traces of cocaine in drinking water?

A: Up to a point.

Q: You mean no?

A: I mean they found traces of the chemical that cocaine gets broken down into

Q: And is that a drug?

A: Not really. It was one component of an unsuccessful treatment for back pain. It is restricted, because it can be turned into cocaine.

Q: How much of this stuff did they find?

A: Almost none. A few nanograms per litre

Q: What’s that in real numbers? If it was really cocaine, how long would it take you to get one dose if you drank  eight glasses of water a day like the doctors recommend?

A: That isn’t actually what the doctors recommend.

Q: Well, then, “like the doctors don’t recommend?”

A: Several centuries.

Q: How can they detect such tiny amounts?

A: They use liquid chromatography to separate out each chemical, and then mass spectroscopy to basically count the molecules.

Q: Ok, impressed now.  The story also mentions “significant amounts of caffeine”. What does that mean?

A: It means “insignificant amounts”, about a million times lower concentration than in a cup of decaffeinated coffee.

Q: At least this is new, though?

A: The same agency reported finding the cocaine metabolite in drinking water in 2011, based on measurements in 2009-10. (PDF, Table 6)

Q: Why is there a video of a drug bust in Spain embedded in the story?

A: Because technology.

• New York Times: In addition, however, “we are able to identify gay bars in Tehran. Moscow too,” said Pete Warden, a co-founder of Jetpac. The company does not want to do that, he added, but he does think it’s important that “we make people aware, get people talking about this.”
• US spending on science, space, and technology correlates with Suicides by hanging, strangulation and suffocation (correlation 0.992)
• Can you stop the Internet knowing you’re pregnant. Maybe?
•  “I’m still a little embarrassed and feel it should be up to the scientists themselves to present the arguments for science.” Bill Bryson

When you hear a car alarm go off, do you even think that someone might be stealing a car? Frequent false positives undermine credibility.

— Stat Fact (@StatFact) May 6, 2014

Gareth Robins has answered this question with a very beautiful visualization generated with a surprisingly compact piece of R code.

Distance to the nearest road in New Zealand

Check out the full size image and the coded here.

As many of you will know, I’m on the working group developing the content of a unit standard in statistical concepts for the National Diploma in Applied Journalism, which journalists with basic qualifications pursue while on the job to extend their skills.

It’s now time for me to ask you to send New Zealand examples of well-written statistically-based stories and poorly-written statistically-based stories that we can use. BUT you need to be able to send me the source data and an explanation (however rough) of what’s wrong with the story and how it could be improved.

I think that teachers may have existing examples that might do, and I would love to see them. You can email me your juicy contributions to statschat@gmail.com.

• David Winter’s comparison of polls to actual votes at the last election
• Pie chart of causes of death in Game of Thrones. It’s a pie chart, but more importantly, there should be a lot more deaths from infectious disease given the setting.  And also from drowning — it’s not clear whether the unreasonable effectiveness of CPR is supposed to be divine intervention or just the typical fictional license
• Tim Harford on health care and health care costs
• A reminder from Texas of where we were heading before the Psychoactive Substances Act

Team Ratings for Round 13

The basic method is described on my Department home page. I have made some changes to the methodology this year, including shrinking the ratings between seasons.

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 74 matches played, 48 of which were correctly predicted, a success rate of 64.9%.

Here are the predictions for last week’s games.

Predictions for Round 13

Here are the predictions for Round 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.

The New Zealand Data Futures Forum was established by the Ministers of Finance and Statistics to have a balanced conversation with New Zealand about the opportunities, risks and benefits of sharing data.

It is particularly keen that people have a say about the potential sharing of big data (information captured through instruments, sensors, internet transactions, email, video, click streams, and other digital activity) held by public and private-sector organisations. How do individuals control their own information and identity while at the same time creating an environment where data can be harnessed for public and economic good?

The Forum will be active until the end of June this year. To post a comment go to https://www.nzdatafutures.org.nz/have-your-say

From Harvard Business Review, 10 kinds of stories to tell with data

For almost a decade I have heard that good quantitative analysts can “tell a story with data.” Narrative is—along with visual analytics—an important way to communicate analytical results to non-analytical people. Very few people would question the value of such stories, but just knowing that they work is not much help to anyone trying to master the art of analytical storytelling. What’s needed is a framework for understanding the different kinds of stories that data and analytics can tell. If you don’t know what kind of story you want to tell, you probably won’t tell a good one.

 

To help with interpreting trends in unemployment, the New York Times has two animated bar charts showing the impact of sampling uncertainty. Here’s a snapshot of one of them (click for the real thing)

There’s a lot of uncertainty in ‘job growth’ figures from a single month, and a lot more uncertainty in month to month changes in estimates of job growth.

Team Ratings for Round 9

The basic method is described on my Department home page. I have made some changes to the methodology this year, including shrinking the ratings between seasons.

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 64 matches played, 35 of which were correctly predicted, a success rate of 54.7%.

Here are the predictions for last week’s games.

Predictions for Round 9

Here are the predictions for Round 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.