293 search results for "evaluation"

Forecasting the Olympics

July 30, 2012
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Forecasting sporting events is a growing research area. The International Journal of Forecasting even had a special issue on sports forecasting a couple of years ago. The London 2012 Olympics has attracted a few forecasters trying to predict medal counts, world records, etc. Here are some of the articles I’ve seen. Which Olympic records get shattered?, Nate Silver, New...

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Changing function scope in GNU R example

July 26, 2012
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In my last post I have discussed how to work around GNU R scoping rules using environment function. This time let us look at a practical example using recode function from car package.First let us look at how&nbs...

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XLConnect 0.2-0

July 23, 2012
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XLConnect 0.2-0

Mirai Solutions GmbH (http://www.mirai-solutions.com) is very pleased to announce the release of XLConnect 0.2-0, which can be found at CRAN. As one of the updates, XLConnect has moved to the newest release of Apache POI: 3.8. Also, the lazy evaluation … Continue reading →

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Announcing eeptools

July 22, 2012
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The LDS_TOOLS package for R has been replaced by the new eeptools package. I am renaming the package for a number of reasons. First, LDS is a technical industry term in education that stands for Longitudinal Data Systems, which is not commonly known an...

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Emulating dynamic scoping in GNU R

July 21, 2012
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By design GNU R uses lexical scoping. Fortunately it allows for at least two ways to simulate dynamic scoping.Let us start with the example code and next analyze it:x <- "global"f1 <- function() cat("f1:", x, "\n")f2 <- function() cat("f2:", e...

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Automatic Hyperparameter Tuning Methods

July 20, 2012
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At MSR this week, we had two very good talks on algorithmic methods for tuning the hyperparameters of machine learning models. Selecting appropriate settings for hyperparameters is a constant problem in machine learning, which is somewhat surprising given how much expertise the machine learning community has in optimization theory. I suspect there’s interesting psychological and

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A weighting function for ‘nls’ / ‘nlsLM’

July 19, 2012
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A weighting function for ‘nls’ / ‘nlsLM’

Standard nonlinear regression assumes homoscedastic data, that is, all response values are distributed normally.  In case of heteroscedastic data (i.e. when the variance is dependent on the magnitude of the data), weighting the fit is essential. In nls (or nlsLM of the minpack.lm package), weighting can be conducted by two different methods: 1) by supplying

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2nd CFP: the 10th Australasian Data Mining Conference (AusDM 2012)

July 10, 2012
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2nd CFP: the 10th Australasian Data Mining Conference (AusDM 2012)

The Tenth Australasian Data Mining Conference (AusDM 2012) Sydney, Australia, 5-7 December 2012 http://ausdm12.togaware.com/ The Australasian Data Mining Conference has established itself as the premier Australasian meeting for both practitioners and researchers in data mining. This year’s conference, AusDM’12, co-hosted … Continue reading →

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Preview of functional programming syntax for futile.paradigm 2.1

July 9, 2012
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Preview of functional programming syntax for futile.paradigm 2.1

I’m developing a streamlined syntax for the next release of futile.paradigm. While this version is backwards compatible, it introduces a …Continue reading »

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Network Visualization of Key Driver Analysis

July 8, 2012
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Network Visualization of Key Driver Analysis

Whatever happened to those evaluations that your airline asked you to complete after taking a flight? They ask you for a number of ratings about buying your ticket, attributes of the plane, the service you received, and if you were satisfied, if you wo...

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