395 search results for "evaluation"

Spatial Randomness Evaluation in R: Monte Carlo Test

May 14, 2012
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Spatial Randomness Evaluation in R: Monte Carlo Test

This post is a some kind of reply to this one.So our goal is to determine whether our point process is random or not. We will use R and spatstat package in particular. Spatstat provides a very handy function for this, that uses K-function combined with...

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Are students’ teaching evaluations influenced by instructors’ looks?

August 3, 2011
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Are students’ teaching evaluations influenced by instructors’ looks?

Are students' teaching evaluations influenced by instructors' looks? ggplot2 may help find the answer.The recent release of RcmdrPlugin.KMggplot2 has made ggplot2 available to those who prefer GUI to the command line interface. With the new plugin for ...

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Forecast estimation, evaluation and transformation

November 9, 2010
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Forecast estimation, evaluation and transformation

I’ve had a few emails lately about forecast evaluation and estimation criteria. Here is one I received today, along with some comments. I have a rather simple question regarding the use of MSE as opposed to MAD and MAPE. If the parameters of a time series model are estimated by minimizing MSE, why do we

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RSI(2) Evaluation

June 28, 2009
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RSI(2) Evaluation

Despite my best efforts, it's been a month since the last post of this series. The first post replicated this simple RSI(2) strategy from the MarketSci Blog using R. The second post showed how to replicate the strategy that scales in/out of RSI(2). ...

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Sensemaking in R: A Plenitude of Models Makes for Good Storytelling

August 3, 2015
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Sensemaking in R: A Plenitude of Models Makes for Good Storytelling

"Sensemaking is a motivated, continuous effort to understand connections (which can be among people, places, and events) in order to anticipate their trajectories and act effectively."- Gary Klein, Brian Moon & Robert HoffmanMaking Sense of Sensema...

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Hockey Elbow and Other Response Time Injuries

July 29, 2015
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Hockey Elbow and Other Response Time Injuries

You've heard of tennis elbow. Well, there's a non-sports, performance injury that I like to call hockey elbow. An example of such an "injury" is shown in Figure 1, which appeared in a recent computer performance analysis presentation. It's a reminder of how easy it is to become complacent when doing performance analysis and possibly end up reaching...

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The complete catalog of argument variations of select() in dplyr

July 28, 2015
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When I read the dplyr vignette, I found a convenient way to select sequential columns such as select(data, year:day). Because I had inputted only column names to select() function, I was deeply affected by the convenient way. On closer inspection, I found that the select() function accepts many types of input. Here, I will enumerate the variety...

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Call for participation: AusDM 2015, Sydney, 8-9 August

July 23, 2015
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Call for participation: AusDM 2015, Sydney, 8-9 August

************************************************************* The 13th Australasian Data Mining Conference (AusDM 2015) Sydney, Australia, 8–9 August 2015 URL: http://ausdm15.ausdm.org/ ************************************************************* The Australasian Data Mining Conference is devoted to the art and science of intelligent data mining: the meaningful analysis of (usually large) data … Continue reading →

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A Tutorial on Loops in R – Usage and Alternatives

July 21, 2015
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A Tutorial on Loops in R – Usage and Alternatives

Introduction In this easy-to-follow R tutorial on loops we will examine the constructs available in R for looping, and how to make use of R’s vectorization feature to perform your looping tasks more efficiently. We will present a few looping examples; then criticize and deprecate these in favor of the most popular vectorized alternatives (amongst The post

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New package "SparkRext" – SparkR extension for closer to dplyr

July 11, 2015
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Apache Spark is one of the hottest products in data science.Spark 1.4.0 has formally adopted SparkR package which enables to handle Spark DataFrames on R.SparkR is very useful and powerful.One of the reasons is that SparkR DataFrames present an API sim...

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