## Le Monde puzzle [#825]

June 18, 2013
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Yet another puzzle which first part does not require R programming, even though it is a programming question in essence: Given five real numbers x1,…,x5, what is the minimal number of pairwise comparisons needed to rank them? Given 33 real numbers, what is the minimal number of pairwise comparisons required to find the three largest ones? […]

## Creating a wordpress single or multisite install using cloudformation and ansible

June 18, 2013
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Intro I recently had to create some sites quickly. After evaluating a few options, setting up a wordpress multisite seemed like a good option. In order to make this change, I setup a wordpress multisite installation with domain mapping. A multisite...

## re:log: Tracking the Movements of Conference Attendees via WiFi

June 18, 2013
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re:log [opendatacity.de] by German data designers OpenDataCity reveals the movements of about 6,700 different electronic devices during re:publica 2013, a prestigious European conference on the topic of Digital Society. A dynamic map of the conferenc...

## Map Stack: Designing a Map in Easy and Fun Ways

June 18, 2013
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Map Stack [stamen.com] by Stamen Design aims to make it radically simpler for lay people to design completely unique, personalized maps. The online visual map design service provides easy access to the color, opacity and brightness of any map backgro...

## Creating a WordPress Single or Multisite Install Using Cloudformation and Ansible

June 18, 2013
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Intro I recently had to create some sites quickly. After evaluating a few options, setting up a wordpress multisite seemed like a good option. In order to make this change, I setup a wordpress multisite installation with domain mapping. A multisite installation is when one wordpress install lets you run multiple websites. I like multisite because it enables me to flexibly manage multiple websites with less duplication of effort than…

## There are no fat sprinters

June 18, 2013
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This post is by Phil. A little over three years ago I wrote a post about exercise and weight loss in which I described losing a fair amount of weight due to (I believe) an exercise regime, with no effort to change my diet; this contradicted the prediction of studies that had recently been released. [...]The post There are no fat sprinters appeared first on Statistical Modeling, Causal Inference, and…

## BCEA 1.3.0

June 18, 2013
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After months of work (although to be fair, we haven't worked 100% full time on this), Andrea and I are nearly ready to publish the next release of BCEA. Andrea has done a brilliant job and is responsible for most of the good new features (NB: see ...

## Job opening! Come work with us!

June 18, 2013
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Postdoctoral position in statistical modeling of social networks A full-time postdoctoral position is available beginning Fall 2014 in the research group of Tian Zheng and Andrew Gelman working on statistical analysis and modeling of social network data, in close cooperation with our experimental collaborators. Four key papers of this project so far are: http://www.stat.columbia.edu/~gelman/research/published/overdisp_final.pdf http://nersp.osg.ufl.edu/~ufruss/documents/mccormick_salganik_zheng10.pdf [...]The post Job opening! Come work with us! appeared first on Statistical Modeling, Causal Inference,…

## Surveys on sensitive topics

June 18, 2013
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Andrew Sullivan (link) has a few questions about a new Pew survey focusing on the LGBT subpopulation. He wonders, for instance, about the high proportion of self-identified bisexuals in this poll. What interests a statistician here is the fact that the poll deals with sensitive matters, which typically present a challenge in terms of survey response, and nonresponse bias. The main accommodation that the pollster (GfK) made here was to…

## googleVis 0.4.3 released with improved Geocharts

June 18, 2013
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The Google Charts Tools provide two kinds of heat map charts for geographical data, the Flash based Geomap and the HTML5/SVG based Geochart. I prefer the Geochart as it doesn't require Flash, but so far there have been two shortcomings with it: I c...

## Software Packages for Graphs and Charts

June 18, 2013
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Graphs can be an important feature of analysis. A graph that has been well designed and put together can make summary statistics much more readable and increase the interpretability. It also makes reports and articles looks more professional. There are many software packages that are available to design great graphs and charts.  This seems to […]

## Bayesian computational tools

June 17, 2013
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I just updated my short review on Bayesian computational tools I first wrote in April for the Annual Review of Statistics and Its Applications. The coverage is quite restricted, as I took advantage of two phantom papers I had started a while ago, one with Jean-Michel Marin, on hierarchical Bayes methods and on ABC. (As […]

## Weak identification provides partial information

June 17, 2013
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Matt Selove writes: My question is about Bayesian analysis of the linear regression model. It seems to me that in some cases this approach throws out useful information. As an example, imagine you have two basketball players randomly drawn from the pool of NBA players (which provides the prior). You’d like to estimate how many [...]The post Weak identification provides partial information appeared first on Statistical Modeling, Causal Inference, and…

## Model Selection in Bayesian Linear Regression

$Model Selection in Bayesian Linear Regression$

Previously I wrote about performing polynomial regression and also about calculating marginal likelihoods. The data in the former and the calculations of the latter will be used here to exemplify model selection. Consider data generated by and suppose we wish to fit a polynomial of degree 3 to the data. There are then 4 regression […] The post Model Selection in Bayesian Linear Regression appeared first on Lindons Log.

## Job opening at new “big data” consulting firm!

June 17, 2013
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David Shor sends along a job announcement for Civis Analytics, which he describes as “basically Obama’s Analytics team reconstituted as a company”: Data Scientist Position Overview Data Scientists are responsible for providing the fundamental data science that powers our work – including predictive analytics, data mining, experimental design and ad-hoc statistical analysis. As a Data [...]The post Job opening at new “big data” consulting firm! appeared first on Statistical Modeling,…

## Back to basics

June 17, 2013
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Today, we review one of the basic principles Ed Tufte very effectively advocated in his famous book: use gridlines and data labels only if absolutely necessary. The enemy is redundancy. Here is a chart that appeared in the New York...

## Repetition factors versus frequency variables

June 17, 2013
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A regular reader noticed my post on initializing vectors by using repetition factors and asked whether that technique would be useful to expand data that are given in value-frequency pairs. The short answer is "no." Repetition factors are useful for defining (static) matrix literals. However, if you want to expand [...]

## Exploratory Data Analysis: Combining Box Plots and Kernel Density Plots into Violin Plots for Ozone Pollution Data

Introduction Recently, I began a series on exploratory data analysis (EDA), and I have written about descriptive statistics, box plots, and kernel density plots so far.  As previously mentioned in my post on box plots, there is a way to combine box plots and kernel density plots.  This combination results in violin plots, and I […]

## Bayesian robust regression for Anscombe quartet

June 16, 2013
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In 1973, Anscombe presented four data sets that have become a classic illustration for the importance of graphing the data, not merely relying on summary statistics. The four data sets are now known as "Anscombe's quartet." Here I present a Bayesian ap...

## Why engineers and poets need to know about statistics

June 16, 2013
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I’m kidding about poets. But lots of people need to understand the three basic areas of statistics, Chance, Data and Evidence. Recently Tony Greenfield, an esteemed applied statistician, (with his roots in Operations Research) posted the following request on a … Continue reading →

## Marginal Likelihood and Model Evidence in Bayesian Regression

$Marginal Likelihood and Model Evidence in Bayesian Regression$

The marginal likelihood or the model evidence is the probability of observing the data given a specific model. This is used in Bayesian model selection and comparison when computing Bayes factor between models, which is simply the ratio of the two respective marginal likelihoods. This can be used to select which covariates to include in […] The post Marginal Likelihood and Model Evidence in Bayesian Regression appeared first on Lindons…

## The scaling of Expected Shortfall

June 16, 2013
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Getting Expected Shortfall given the standard deviation or Value at Risk. Previously There have been a few posts about Value at Risk and Expected Shortfall. Properties of the stable distribution were discussed. Scaling One way of thinking of Expected Shortfall is that it is just some number times the standard deviation, or some other number … Continue reading →

## Sunday data/statistics link roundup (6/16/13 – Father’s day edition!)

June 16, 2013
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Datapalooza! I'm wondering where my invite is? I do health data stuff, pick me, pick me! Actually it does sound like a pretty good idea - in general giving a bunch of smart people access to interesting data and real … Continue reading →