305 search results for "market research"

Emerging as Low Vol

October 2, 2012
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Emerging as Low Vol

Extending the series begun with When Russell 2000 is Low Vol, I thought I should take a look at Emerging Market stocks during periods of low relative volatility to the S&P 500.  So you can replicate even without access to expensive data, let

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A Brief Tip on Generating Fractional Factorial Designs in R

October 1, 2012
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A number of marketing researchers use the orthoplan procedure in SPSS to generate fractional factorial designs.  It is not surprising, then, that I received a number of questions concerning the recent article in the Journal of Statistical Software by Hideo Aizaki on “Basic Functions for Supporting an Implementation of Choice Experiments in R.”  To summarize their issues,...

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Using R in Political Controversies: Unemployment Reduction Prowess Under Bush versus Obama Years

September 27, 2012
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Using R in Political Controversies: Unemployment Reduction Prowess Under Bush versus Obama Years

Editor’s note: R-bloggers does not take a political side. Since this is an important topic, this post has the comments turned on. Also, If you wish to write a reply post (which includes an R context), you are welcome to contact me to have it published. This post was written by Prof. H. D. Vinod. Fordham University, New York.

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Association Rule Learning and the Apriori Algorithm

September 26, 2012
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Association Rule Learning and the Apriori Algorithm

Association Rule Learning (also called Association Rule Mining) is a common technique used to find associations between many variables. It is often used by grocery stores, retailers, and anyone with a large transactional databases. It’s the same way that Target knows your pregnant or when you’re buying an item on Amazon.com they know what else you want

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Learning Kernels SVM

September 25, 2012
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Learning Kernels SVM

Machine Learning and Kernels A common application of machine learning (ML) is the learning and classification of a set of raw data features by a ML algorithm or technique. In this context a ML kernel acts to the ML algorithm … Continue reading →

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Podcast interview with Michael Kane

September 17, 2012
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In this podcast interview with Michael Kane, Data Scientist and Associate Researcher at Yale University, Michael discusses the R statistical programming language, computational challenges associated with big data, and two projects involving data analysis he conducted on the stock market "flash crash" of May 6, 2010, and the tracking of transportation routes bird flu H5N1. Michael also...

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Slightly-more-than-basic sentiment analysis

September 14, 2012
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I became interested in sentiment analysis a few months ago as a matter of pure practicality. The company I work for does a lot of customer-satisfaction surveys. Respondents rate various aspects of our products, but they also have the opportunity to answer a bunch of open-ended questions in their own voices. That kind of information

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Item Response Theory: Developing Your Intuition

September 10, 2012
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Item Response Theory: Developing Your Intuition

Suppose that you accepted my argument from the last two posts on halo effects and bifactor models.  As you might recall, I argued that when respondents complete rating scales, they predominating rely on their generalized impression with a more minor role played by the specific features that the ratings were written to measure.  Consequently, we...

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New Attribution Functions for PortfolioAnalytics

September 1, 2012
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New Attribution Functions for PortfolioAnalytics

Another Google Summer of Code (GSoC) project this summer focused on creating functions for doing returns-based performance attribution. I’ve always been a little puzzled about why this functionality wasn’t covered already, but I think that most analysts do this kind of work in Excel. That, of course, has its own perils. But beyond the workflow

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Structural Equation Modeling: Separating the General from the Specific (Part II)

August 26, 2012
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Structural Equation Modeling: Separating the General from the Specific (Part II)

As promised in Halo Effects and Multicollinearity (my last post), I will show how to run a confirmatory factor analysis in R to test our bifactor model.  In addition, I will include a dependent variable and fit a structural equation mode...

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