Tuesday, December 27, 2005

AIDS statistics

IndexMundi also has some excellent drawing capabilities; for instance, the screenshot below shows the countries with the highest reported rates of AIDS... the top eight countries are in Southern Africa.



In a few cases, it's not clear if the basic numbers are correct - for instance, this graph shows Zimbabwe having 1.8 people living with AIDS - that's because Zimbabwe reports people dying of AIDS rather than living with AIDS.

Correlations

Miguel Barrientos' IndexMundi allows you to plot correlations of several values... [IM Blog]

Migration and GDP per capita - slightly positive, indicating that wealthier countries have higher immigration rates (some interesting cause/effect arguments here)

Richer countries have lower infant mortality rates and have higher life expectancy and lower fertility and higher literacy and may not be getting richer(!) and lower unemployment and lower industrial production growth rate (!)

Sunday, December 25, 2005

The Mystery of the Disappearing Teaspoons

Megan Lim and other Melbourne researchers have produced a definite contender for a future IgNobel prize in the form of their five-month study on "the displacement of Camellia sinensis spathulatus" a.k.a. teaspoons. They report their results in a light-hearted holiday issue of the British Medical Journal.

They discreetly labeled 70 teaspoons, placed in tearooms around their institute (of 140 people) and observed, every week over five months, which ones were left. The result was that "56 (80%) of the 70 teaspoons disappeared during the study." Also, "the rate of loss was not influenced by the teaspoons' value" as shown in the picture below (which is from their research paper and which will probably get me into trouble with the journal for copyright breach).



Actually, looking at the graph above, expensive teaspoons did disappear more quickly initially, so we will clearly require further studies to verify their conclusion.

They go on further to note that "the half life of the teaspoons was 81 days" - that means that it takes about 2.5-3 months for half the teaspoons to disappear. However, this differs depending on how many people have access to the spoons - "The half life of teaspoons in communal tearooms (42 days) was significantly shorter than for those in rooms associated with particular research groups (77 days)."

The BMJ also allows people to respond to the study; one reader (Philip Colquitt) provides a good reason for why this kind of study is of great importance:

... if whole nations can be invaded by other nations, on the pretext of the existence of weapons of mass destruction[WMD], which WMD disappear without rational explanation, this suggests that primates(homo sapiens) may well be on the right track in trying to master spoon detection before going on to the more advanced stuff.

Articles about this. (Link to Google News)