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Resampling Hierarchically Structured Data Recursively

That's a mouthful! I presented this topic to a group of Vandy statisticians a few days ago. My notes (essentially reproduced in this post) are recorded at the Dept. of Biostatistics wiki:...

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useR! 2012 Deadlines Approaching: Registration, Hotels, Student Scholarships

Forwarded from Frank Harrell: DEADLINES FAST APPROACHING – 8th Annual International R User Conference useR! 2012, Nashville, Tennessee USA Registration Deadlines: Early Registration: Passed Regular...

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Update: Parameters as Population Quantities

Some time ago, I had an ineloquent and less-than-cordial online discussion with a commenter on this site, partially about how statisticians define the term "parameter". This post is just to quote a...

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Bayesian credible intervals in the mainstream medical literature

I have sometimes heard complaints from collaborators that it will be impossible to have their work published in the mainstream literature unless a p-value is reported. This post is to report yet...

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Bank of America 1% Cash Rewards Aren't Really 1%

Bank of America (BoA) has a "Cash Rewards" credit card that pays "1% cash back everywhere, every time"1. But if you read the fine print, it's clear that the reward is almost always less than 1%. Here's...

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Revised graph for BAC 1% cash rewards

Thanks to Anthony Damico who alerted me to an error in the Bank of America's 1% cash rewards figure in my last post. The plot shows the true reward percentage as a function of purchase amount. A key...

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Breakthroughs in the sas7bdat Reverse Engineering Effort

Due largely to the work of Clint Cummins, the sas7bdat file format has become a bit less shrouded. In particular, we now know the following: how to detect files with compressed data (and fail...

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Simulated Power/Precision Analysis

I cringe when I see research proposals that describe a sophisticated statistical approach, yet do not evaluate this approach in their power/precision/sample size planning. It's often the case that a...

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Generalized Pairs Plot: It's about time!

JW Emerson, WA Green, B Schloerke, J Crowley, D Cook, H Hofmann, H Wickham (2013) The Generalized Pairs Plot. Journal of Computational and Graphical Statistics 22(1). Here's a free preprint version....

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Identify 2/3 vacation photos, win $5 Starbucks gift card

I have a $5 Starbucks gift card that I simply can't remember to use; I've had it since Christmas. So, I will mail it (within the U.S.A.) to the first commenter who can identify the longitude/latitude...

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Hurray! An R Connections API!

I waited until April 3 to post this, so it wouldn't be taken as an April Fool's joke! A recent R News item announces that we now have a bona fide mechanism to create custom connections in R! This makes...

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Descending Text in Righthand Margin of R Graphics à la mtext

There was an R-help thread in January regarding text in the righthand margin of an R graphic, where the text should be rendered in reading order from top to bottom. The base R function mtext is used to...

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A Recipe for Trellis/Faceted Plots Using Base R Graphics

I frequently use lattice and ggplot2 to create trellis/faceted graphics. But, I gave up using these packages in a recent application, where I had initially constructed a complex graphic using the base...

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Image CGI with R

I received an email recently with a question about using R in the common gateway interface (CGI) framework to create and pass image data to the web browser. I posted to stackoverflow about this some...

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Alternatives to model diagnostics for statistical inference?

Consider the problem of making statistical inferences, as opposed to predictions. The product of statistical inference is a probabilistic statement about a population quantity, for example a 100(1-)%...

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Making inferences about unusual population quantities.

This post builds on my last: Alternatives to model diagnostics for statistical inference?, where I had claimed that we could make quality inferences about the best linear approximation to a quadratic...

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Read sas7bdat files in R with GGASoftware Parso library

... using the new R package sas7bdat.parso. The software company GGASoftware has extended the work of myself and others on the sas7bdat R package by developing a Java library called Parso, which also...

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Some 3D Graphics (rgl) for Classification with Splines and Logistic...

This semester I'm teaching from Hastie, Tibshirani, and Friedman's book, The Elements of Statistical Learning, 2nd Edition. The authors provide a Mixture Simulation data set that has two continuous...

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More 3D Graphics (rgl) for Classification with Local Logistic Regression and...

This post builds on a previous post, but can be read and understood independently. As part of my course on statistical learning, we created 3D graphics to foster a more intuitive understanding of the...

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Simulation-based power analysis using proportional odds logistic regression

Consider planning a clinicial trial where patients are randomized in permuted blocks of size four to either a 'control' or 'treatment' group. The outcome is measured on an 11-point ordinal scale (e.g.,...

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