147 search results for "heatmap"

Do the Simpsons characters like each other?

July 21, 2013
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Do the Simpsons characters like each other?

One day, while I was walking around Cambridge, I had a random thought — how do the characters on the Simpsons feel about each other? It doesn’t take long to figure out how Homer feels about Flanders (hint: he doesn’t always like him), or how Burns feels about everyone, but how does Marge feel about Bart? ...

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Do the Simpsons characters like each other?

July 21, 2013
By
Do the Simpsons characters like each other?

One day, while I was walking around Cambridge, I had a random thought -- how do the characters on the Simpsons feel about each other? It doesn't take long to figure out how Homer feels about Flanders (hint: he doesn't always like him), or how Burns feels about everyone, but how does Marge feel about Bart? How does Flanders...

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Using R: Two plots of principal component analysis

June 26, 2013
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Using R: Two plots of principal component analysis

PCA is a very common method for exploration and reduction of high-dimensional data. It works by making linear combinations of the variables that are orthogonal, and is thus a way to change basis to better see patterns in data. You either do spectral decomposition of the correlation matrix or singular value decomposition of the data

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The Reorderable Data Matrix and the Promise of Pattern Discovery

June 12, 2013
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The Reorderable Data Matrix and the Promise of Pattern Discovery

We typically start with the data matrix, a rectangular array of rows and columns.  If we type its name on the R command line, it will show itself.  But the data matrix is hard to read, even when there are not many rows or columns.  The heat map is a visual alternative.  All you need is the R function...

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Biostatisticians… beware of fuzzy researchers!

June 11, 2013
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Biostatisticians… beware of fuzzy researchers!

In the last days I was thinking about about how researchers could collaborate efficiently with their experts in statistics. With the increasing complexity in science, interchanging information can be crucial to get the best results. But what happens when a … Sigue leyendo →

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Analysis of Cable Morning Trade Strategy

May 29, 2013
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Analysis of Cable Morning Trade Strategy

A couple of years ago I implemented an automated trading algorithm for a strategy called the “Cable Morning Trade”. The basis of the strategy is the range of GBPUSD during the interval 05:00 to 09:00 London time. Two buy stop orders are placed 5 points above the highest high for this period; two sell stop

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BISON USGS species occurrence data

May 27, 2013
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BISON USGS species occurrence data

The USGS recently released a way to search for and get species occurrence records for the USA. The service is called BISON (Biodiversity Information Serving Our Nation). The service has a web interface for human interaction in a browser, and two APIs (application programming interface) to allow machines to interact with their database. One of the...

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BISON USGS species occurrence data

May 27, 2013
By
BISON USGS species occurrence data

The USGS recently released a way to search for and get species occurrence records for the USA. The service is called BISON (Biodiversity Information Serving Our Nation). The service has a web interface for human interaction in a browser, and two APIs (application programming interface) to allow machines to interact with their database. One of the...

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Omni test for statistical significance

May 9, 2013
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Omni test for statistical significance

In survey research, our datasets nearly always comprise variables with mixed measurement levels – in particular, nominal, ordinal and continuous, or in R-speak, unordered factors, ordered factors and numeric variables. Sometimes it is useful to be able to do blanket tests of one set of variables (possibly of mixed level) against another without having to

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Writing from R to Excel with xlsx

May 1, 2013
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Writing from R to Excel with xlsx

Paul Teetor, who is doing yeoman’s duty as one of the organizers of the Chicago R User Group (CRUG), asked recently if I would do a short presentation about a “favorite package”.  I picked xlsx, one of the many packages that provides a bridge between spreadsheets and R.  Here are the slides from my presentation

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