2151 search results for "Map"

What 5,728.986 miles look like…

November 10, 2011
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What 5,728.986 miles look like…

Time Series as calendar heat maps + All of my running data since April 1, 2009 = Generated by the following code: #Sample Code based on example program at: source(file = "calendarHeat.R") run<- read.csv("log.csv", header = TRUE, sep=",") sum(run$Distance) date <- c() for (i in 1: dim(run)){ if(run$DistanceUnit== 'Kilometer'){ miles <- c(miles,run$Distance * 0.62) }

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PostGIS Quickie

November 10, 2011
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Today I needed to cut out a rectangle of geologic data from a state-wide map in an AEA coordinate system, using a bounding box from a UTM zone 10 region, with the output saved in UTM zone 10 coordinates. PostGIS makes this type of operation very simple...

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In case you missed it: October Roundup

November 10, 2011
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In case you missed them, here are some articles from October of particular interest to R users. The creator of the ggplot2 package, Hadley Wickham, shares details on some forthcoming big-data graphics functions (based on research sponsored by Revolution Analytics). A list of several dozen free data sources that can easily be imported into R. Bob Muenchen gave a...

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Geometric Efficient Frontier

November 9, 2011
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Geometric Efficient Frontier

What is important for an investor? The rate of return is at the top of the list. Does the expected rate of return shown on the mean-variance efficient frontier paints the full picture? If investor’s investment horizon is longer than one period, for example 5 years, than the true measure of portfolio performance is Geometric

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What the frack? Does hydraulic fracturing lead to increased earthquakes?

November 8, 2011
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What the frack?  Does hydraulic fracturing lead to increased earthquakes?

Earthquakes are normal occurrences along the boundaries of major plate margins, such as along the San Andreas fault system of California,  and are less common within plate interiors.  Try telling that, however, to the citizens of Oklahoma who...

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Using Text Mining to Find Out What @RDataMining Tweets are About

November 8, 2011
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Using Text Mining to Find Out What @RDataMining Tweets are About

This post shows an example on text mining of Twitter data with R packages twitteR, tm and wordcloud. Package twitteR provides access to Twitter data, tm provides functions for text mining, and wordcloud visualizes the result with a word cloud. … Continue reading →

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Rcpp talk at Seattle RUG next month

November 6, 2011
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The Seattle R User Group was kind enough to invite me to give a talk about R, C++ and Rcpp. So if you can make it to the Thomas building of the Fred Hutchinson Cancer Research Center in Seattle, WA, on December 7, I would love to see you there. I ha...

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Modern Portfolio Optimization Theory: The idea

November 3, 2011
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Modern Portfolio Optimization Theory: The idea

We were recently given a lecture (by Dr. Susan Thomas) on Harry Markowitz portfolio optimization theory, and I was really fascinating with the noble laureate's story of how he found it difficult to convince his guide about the importance of h...

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Maximizing Omega Ratio

November 3, 2011
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Maximizing Omega Ratio

The Omega Ratio was introduced by Keating and Shadwick in 2002. It measures the ratio of average portfolio wins over average portfolio losses for a given target return L. Let x.i, i= 1,…,n be weights of instruments in the portfolio. We suppose that j= 1,…,T scenarios of returns with equal probabilities are available. I will

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Use case: combining taxize and rgbif

November 1, 2011
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Use case: combining taxize and rgbif

Sure thing….this is just the sort of thing for which rOpenSci is being built. A colleague of mine recently saw our packages in development and thought, “Hey, that could totally make my life easier.”   What was made easier you ask?   This was his situation: He had a list of ca. 1200 species of

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