1288 search results for "excel"

Structural Equation Modeling: Separating the General from the Specific (Part II)

August 26, 2012
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Structural Equation Modeling: Separating the General from the Specific (Part II)

As promised in Halo Effects and Multicollinearity (my last post), I will show how to run a confirmatory factor analysis in R to test our bifactor model.  In addition, I will include a dependent variable and fit a structural equation mode...

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A Chlorpleth Map of Free and Reduced Price Lunch in R

August 26, 2012
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A Chlorpleth Map of Free and Reduced Price Lunch in R

Charles Blow has an excellent op-ed in the New York Times about public education this week. The most important point he makes is that the defunding of public education is coming at precisely the time when American school children are most vulnerable:No...

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Why R for Mass Spectrometrist and Computational Proteomics

August 25, 2012
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Why R for Mass Spectrometrist and Computational Proteomics

Why R:Actually, It is a common practice the integration of the statistical analysis of the resulted data and in silico predictions of the data generated in your manuscript and your daily research. Mass spectrometrist, biologist and bioinformaticians c...

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Does playing baseball shorten your lifespan? (Answer: No.)

August 24, 2012
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Does playing baseball shorten your lifespan? (Answer: No.)

A National Institute for Occupational Safety and Health study, published in March, found that professional American football (NFL) players lived longer, on average, than similar "mere mortals" in the general population. Football is a dangerous sport, so that might seem surprising at first, until you consider the fact that NFL players are elite sportsmen: only the strongest, fastest and...

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2014 Winter Olympics: Home Court Advantage – Russia

August 22, 2012
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2014 Winter Olympics: Home Court Advantage – Russia

"Russia is a riddle wrapped in a mystery inside an enigma."  -- Winston Churchill, radio address in 1939 A couple of weeks ago, Graph of the Week published an article describing the significant improvement in medals won by the host...

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ARMA Models for Trading

August 21, 2012
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ARMA Models for Trading

In this tutorial I am going to share my R&D and trading experience using the well-known from statistics Autoregressive Moving Average Model (ARMA). There is a lot written about these models, however, I strongly recommend Introductory Time Series with R, which I find is a perfect combination between light theoretical background and practical implementations in

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Mid-August flotsam

August 20, 2012
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Mid-August flotsam

Reached mid-semester point, with quite a few new lectures to prepare. Nothing extremely complicated but, as always, the tricky part is finding a way to make it meaningful and memorable. Sometimes, and this is one of those times, I sound … Continue reading →

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Another comparison of heuristic optimizers

August 20, 2012
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Another comparison of heuristic optimizers

A herd of heuristic algorithms is compared using a portfolio optimization. Previously “A comparison of some heuristic optimization methods” used two simple and tiny portfolio optimization problems to compare a number of optimization functions in the R language. This post expands upon that by using a portfolio optimization problem that is of a realistic size … Continue reading...

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Twitter coverage of the ISMB 2012 meeting: some statistics

August 15, 2012
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Twitter coverage of the ISMB 2012 meeting: some statistics

OK, let’s do this: some statistics and visualization of the tweets for ISMB 2012. First, thanks to Stephen Turner who got things started in this post at his excellent blog, Getting Genetics Done. Subscribe to his feed if you don’t already do so. I’ve created a Github repository for this project (and future Twitter-related work).

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The Statistical Sleuth (second edition) in R

August 14, 2012
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The Statistical Sleuth (second edition) in R

For those of you who teach, or are interested in seeing an illustrated series of analyses, there is a new compendium of files to help describe how to fit models for the extended case studies in the Second Edition of the Statistical Sleuth: A Course in...

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