Monthly Archives: August 2013

Cronbach to the future

August 6, 2013
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One fascinating thing about working in the area of psychological statistics is how hard it is to move people away from reliance on bad, inefficient or otherwise problematic methods. My own view - informed to some extent by the literature, by experience and by anecdote is that it isn't sufficient merely to establish than the standard approach is wrong....

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How to choose a new business location with R

August 6, 2013
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How to choose a new business location with R

This guest post is by Rodolfo Vanzini. Rodolfo is senior partner at eXponential.it — an asset management consultancy based in Italy — and advises clients on investment management issues. He taught at the University of Siena and is an analytics professional. With an economist education and a financial markets expertise four years ago I thought I couldn't be of...

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JSM 2013 – Monday

August 6, 2013
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JSM 2013 – Monday

I am currently attending the 2013 Joint Statistical Meeting in Montreal. I will try to share a few if the things that I take away each day. Last night (Monday) I attended the JSM keynote speaker with Nate Silver and it proved to be a very interesting discussion.  Silver is best known for his work

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The Stats Chat Blog

August 6, 2013
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Recently, I've begun following the Stats Chat blog. Run by the Department of Statistics at the University of Auckland - the largest statistics department in New Zealand or Australia (and the birthplace of R) - this blog apparently started in April of this year.It's aim is:"to foster discussion of data around us, particularly in the media, and...

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Read the source code

August 6, 2013
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Read the source code

The other day, there was a bit of a twitter conversation about qqline in R. It made me think: how exactly is the line produced by qqline chosen? I seemed to recall that the line was through the first and third quartiles. An advantage of R is that you can just type the name of

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I Want ggplot2/lattice and d3 (gridSVG–The Glue)

August 6, 2013
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I Want ggplot2/lattice and d3 (gridSVG–The Glue)

I really like interactive graphics, especially when they come straight from R.  I posted a lot about rCharts, but it is not the only way.  In my mind there are three types of glue to link R to SVG/HTML/Javascript: Let R do the data and then send the data to Javascript to create the SVG graphics....

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Tabular Data I/O in Julia

August 6, 2013
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Importing tabular data into Julia can be done in (at least) three ways: reading a delimited file into an array, reading a delimited file into a DataFrame and accessing databases using ODBC. Reading a file into an array using readdlm The most basic way to read data into Julia is through the use of the Tabular Data I/O...

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Informative leaflet on R

August 6, 2013
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Informative leaflet on R

We often meet clients who might have never heard of R or who are not really familiar with the power of that nice open-source statistical engine. Instead of explaining the advantages and potentials of using R personally at meetings, we came up with...

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Setting axes limits with googleVis

August 6, 2013
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I posted about the various googleVis axis options for base charts, such as line, bar and area charts earlier, but I somehow forgot to mention how to set the axes limits.Unfortunately, there are no arguments such as ylim and xlim. Instead, the Google Ch...

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Item Equating with same Group – SAT, ACT example

August 5, 2013
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Item Equating with same Group – SAT, ACT example

# Item equating is the practice of making the results from two # different assessments equivalent. This can be done by either# 1. having the same group take both assessments# 2. having equivalent groups take the different assessments# 3. having non-eq...

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