At DSN, we’ve been playing a bit with FetchClimate Explorer from Microsoft Research. It lets one define regions of the globe over which it superimposes spatial and time series data concerning temperature, precipitation, sunlight, and, pictured above, wind speed.
MENTALLY MULTIPLY NUMBERS BY THEMSELVES
Assume you know your multiplication tables up to 10×10. Here’s how to compute the squares of numbers from 11 to 100.
Two posts ago we showed you the digit sound system for remembering numbers. This week we provide two computer programs to help you create mnemonics.
At Decision Science News, we have all kinds of numbers memorized: IP addresses, passport numbers, phone numbers, bank account numbers, logarithms, etc. Once you have stuff like this memorized, you’ll start to realize how much less of a hassle it is to have things in memory rather than on paper or disk. Besides, it’s fun.
But how is it done?
It is done with the digit-sound method, which we learned from Professor Jaap Murre’s neuroMod site at the University of Amsterdam.
A famous finance professor once told us that good diversification meant holding everything in the world. Fine, but in what proportion?
Suppose you could invest in every country in the world. How much would you invest in each? In a market-capitalization weighted index, you’d invest in each country in proportion to the market value of its investments (its “market capitalization”). As seen above, the market-capitalization of the USA is about 30%, which would suggest investing 30% of one’s portfolio in the USA. Similarly, one would put 8% in China, and so on. All this data was pulled from the World Bank, and at the end of this post we’ll show you how we did it.
Decision Science News has posted before on Zhao, Lynch, and Chen’s practical article on mediation analysis. John Lynch has written the following, re-emphasizing the article’s main points:
ON COMMITMENT DEVICE BUSINESSES AND SOFT CONTRACTS This week, our former home, the Center for the Decision Sciences at Columbia University, has turned us on to this article about a fitness plan that charges you more if you work out less. Yes, it’s a business putting applied behavioral economics to work, not unlike Stickk.com or […]
HOW TO STOP THE SELLING OF CORRELATION AS CAUSATION? Decision Science News does not read news often. (We took Herbert Simon’s advice that checking the news every week or so is enough and are much happier since). However, each time we do we see headlines of the following sort: Want to live longer? Get a […]
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