2251 search results for "MAP"

Phase space plot of the kicked rotor

April 21, 2012
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Phase space plot of the kicked rotor

In the idealized physical world, a rotor is simply a mass attached to an axis of length , free to move in the plane. Gravity and friction are absent. Such a rotor becomes a kicked rotor if it is periodically hit with a hammer. Every kick transfers momentum to the rotor and the time between

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Sanitizing data in SAP HANA with R

Sanitizing data in SAP HANA with R

From April 10 to April 11, my team (Anne, Juergen and myself) host an InnoJam in Boston. It was a really great event, but the data provided by the City of Boston wasn't exactly in the best shape, so we took a lot of efforts (with a help of the SAP Guru...

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When R met SAP Gateway

When R met SAP Gateway

A couple of days ago, I was toying with the idea of doing something with SAP Gateway...I thought of using SUP, but as I recently wrote 2 blogs about it, I decided to go back to one of my favorite programming languages...R...So...Gateway can be consumed...

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From the Guardian’s data blog: Visualising risk

April 20, 2012
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From the Guardian’s data blog: Visualising risk

The Guardian published a nice summary and link collection of an interdisciplinary visualisation workshop hosted by Microsoft dedicated to visualising probability and risk. Check it out here.OECD better life indexThe links I found most interesting were ...

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Efficient Frontier of Funds and Allocation Systems

April 18, 2012
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Efficient Frontier of Funds and Allocation Systems

I did a very basic experiment in Efficient Frontier of Buy-Hold and Tactical System where I determined the efficient frontier of the S&P 500 with itself transformed by a Mebane Faber 10-month moving average tactical allocation. The result was inter...

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Quickly Explore the Penn World Tables in R

April 17, 2012
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Quickly Explore the Penn World Tables in R

The Penn World Tables are one of the greatest source of worldwide macroeconomic data, but dealing with its web interface is somewhat cumbersome. Fortunately, the data is also available as a R package on CRAN. Having some tools at hand … Continue reading →

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How NOAA uses R to forecast river flooding

April 16, 2012
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How NOAA uses R to forecast river flooding

Thanks to the lower-than-usual snowfall over most of the US this past winter, there's low risk of major flooding as the snow melts this Spring (for the first time in four years!). Nonetheless, being able to forecast river flood events is of critical importance to local emergency managers, water & electric utilities, river navigation companies, and the US Army...

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Registration for R/Finance 2012 is Open

April 15, 2012
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Registration for R/Finance 2012 is Open

Registration has been open for a while, but I wanted to point out the pre-conference seminars. Registrations are strong this year, so if you’re interested you’ll need to sign up before they sell out. Register here… As you probably know by now, the fourth annual R/Finance conference for applied finance using R will be held

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Implementing the Exact Binomial Test in Julia

April 14, 2012
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One major benefit of spending my time recently adding statistical functionality to Julia is that I’ve learned a lot about the inner guts of algorithmic null hypothesis significance testing. Implementing Welch’s two-sample t-test last week was a trivial task because of the symmetry of the null hypothesis, but implementing the exact binomial test has proven

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Surveys measure what people do, not what people think

April 13, 2012
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In my previous post, I wrote about ways scale choice could distort the ways survey results portray the things they are supposed to measure. This certainly isn’t a new issue – researchers who use surveys often go to great lengths to ensure that their surveys are valid and reliable, which in this context usually means

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