324 search results for "evaluation"

On Volatility Proxy

October 23, 2012
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Volatility is unobserved. Hence we need to use observed quantity as a proxy. Every once in a while I still see people using squared daily return as a proxy. However, there is ample evidence that it is a bad one. … Continue reading → Related posts: Intra-day Volatility Pattern When we speak about volatility we...

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Carl Morris Symposium on Large-Scale Data Inference (2/3)

October 20, 2012
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Carl Morris Symposium on Large-Scale Data Inference (2/3)

Continuing the summary of last week’s symposium on statistics and data visualization (see part 1 and part 3)… Here I describe Dianne Cook’s discussion of visual inference, and Rob Kass’ talk on statistics in cognitive neuroscience. [Edit: I've added a few … Continue reading →

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Agreement between code readability ratings given by students

October 13, 2012
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Agreement between code readability ratings given by students

I have previously written about how we know nothing about code readability and questioned how the information content of expressions might be calculated. Buse and Weimer ran a very interesting experiment that asked subjects to rate short code snippets for readability (somebody please rerun this experiment using professional software developers). I’m interested in measuring how

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Product revenue prediction with R – part 2

October 8, 2012
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Product revenue prediction with R – part 2

After development of predictive model for transactional product revenue -(Product revenue prediction with R – part 1), we can further improvise the model prediction by modifications in the model. In this post, we will see what are the steps required for model improvement. With the help of a set of model summary parameters, the data

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Oracle R Enterprise Tutorial Series on Oracle Learning Library

October 2, 2012
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Oracle Server Technologies Curriculum has just released the Oracle R Enterprise Tutorial Series, which is publicly available on Oracle Learning Library (OLL). This 8 part interactive lecture series with review sessions covers Oracle R Enterprise ...

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Scraping pages and downloading files using R

October 1, 2012
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Scraping pages and downloading files using R

I have written a few posts discussing descriptive analyses of evaluation of National Standards for New Zealand primary schools.The data for roughly half of the schools was made available by the media, but the full version of the dataset is … Continue reading →

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ROracle support for TimesTen In-Memory Database

September 27, 2012
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Today's guest post comes from Jason Feldhaus, a Consulting Member of Technical Staff in the TimesTen Database organization at Oracle.  He shares with us a sample session using ROracle with the TimesTen In-Memory database.  Beginning in ve...

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DESeq vs edgeR Comparison

September 18, 2012
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DESeq vs edgeR Comparison

Update (Dec 18, 2012): Please see this related post I wrote about differential isoform expression analysis with Cuffdiff 2.DESeq and edgeR are two methods and R packages for analyzing quantitative readouts (in the form of counts) from high-throughput e...

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Changes in optimization performance of gcc over time

September 16, 2012
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Changes in optimization performance of gcc over time

The SPEC benchmarks came out a year after the first release of gcc (in fact gcc was and still is one of the programs included in the benchmark). Compiling the SPEC programs using the gcc option -O2 (sometimes -O3) has always been the way to measure gcc performance, but after 25 years does this way

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BCEA examples

September 13, 2012
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I've prepared a document (which I've put on the website here, together with some scripts at this page) which I think is helpful, if you're trying to work out BCEA. I have never really thought of this, but I believe that when you write an acad...

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