1129 search results for "latex"

rfigshare tutorial

November 6, 2012
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Recently we at rOpenSci released our rfigshare package up on cran (or you can check out the most up to date version on github. So what’s so great about being able to create figshare articles through R? For some time now I’ve been advocating the use of a workflow that involves documents written in R...

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Simulating Multiple Asset Paths in R

November 5, 2012
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Simulating Multiple Asset Paths in R

I recently came across the Optimal Rebalancing Strategy Using Dynamic Programming for Institutional Portfolios by W. Sun, A. Fan, L. Chen, T. Schouwenaars, M. Albota paper that examines the cost of different rebablancing methods. For example, one might use calendar rebalancing: i.e. rebalance every month / quarter / year. Or one might use threshold rebalancing:

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Why pictures are so important when modeling data?

October 31, 2012
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Why pictures are so important when modeling data?

(bis repetita) Consider the following regression summary,Call: lm(formula = y1 ~ x1)   Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 3.0001 1.1247 2.667 0.02573 * x1 0.5001 0.1179 4.241 0.00217 **...

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Can We Live Without Backslashes?

October 30, 2012
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Can We Live Without Backslashes?

Two months ago there was a discussion in the ESS mailing list about Emacs/ESS started by Paul Johnson, who claimed "Emacs Has No Learning Curve". While this sounds impossible, he really has some good points, e.g. he encourages beginners to look at the ...

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Visiting FHCRC, JHSPH and Meeting Xi’an

October 29, 2012
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Visiting FHCRC, JHSPH and Meeting Xi’an

I have been traveling during the last two weeks. I visited Fred Hutchinson Cancer Research Center on Oct 16 and the Department of Biostatistics at Johns Hopkins at the invitation of Simply Statistics on Oct 23. Today Christian Robert was visiting our department at Iowa State, and I also talked to him. It is really cool...

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Power and Sample Size Analysis: Z test

October 17, 2012
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Power and Sample Size Analysis: Z test

This article provide a brief background about power and sample size analysis. Then, power and sample size analysis is computed for the Z test. Continue reading →

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Fractals and Kronecker product

October 17, 2012
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Fractals and Kronecker product

A few years ago, I went to listen to Roger Nelsen who was giving a talk about copulas with fractal support. Roger is amazing when he gives a talk (I am also a huge fan of his books, and articles), and I really wanted to play with that concept ...

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Ready-made model comparison tables for journals

October 15, 2012
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Ready-made model comparison tables for journals

If you're reporting on the results of a statistical analysis for a journal or report, you'll probably be building a table comparing two or models. Such tables may include variables in the model, parameter estimates, and p-values, and model summary statistics. If you want to include such tables based on lm, glm, svyglm, gee, gam, polr, survreg or coxph...

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Compound Poisson and vectorized computations

October 12, 2012
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Compound Poisson and vectorized computations

Yesterday, I was asked how to write a code to generate a compound Poisson variables, i.e. a series of random variables  where  is a counting random variable (here Poisson disributed) and where the 's are i.i.d (and ind...

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Working with Bipartite/Affiliation Network Data in R

September 30, 2012
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Working with Bipartite/Affiliation Network Data in R

Data can often be usefully conceptualized in terms affiliations between people (or other key data entities). It might be useful analyze common group membership, common purchasing decisions, or common patterns of behavior. This post introduces bipartite/affiliation network data and provides … Continue reading →

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