255 search results for "Anova"

Gas price seasonality

February 18, 2010
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Gas price seasonality

Last spring I read “Quantitative Trading” by Ernest P. Chan. In his book, he suggested to buy gas futures contract at the end of February and sell it later, in March. Today, I decided to test this strategy by using R-language. The most important thing for such investigation is data. For this purpose, I used this

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Making publication-ready tables with xtable

February 12, 2010
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Making publication-ready tables with xtable

When you use R at the command-line, the textual output is limited by the medium: one monospaced font, with no typesetting of any kind. That's great when you're doing exploratory analysis, but what about when you want to include R output in a report or publication? In other words, what if you want to convert this Analysis of Variance...

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R Tutorial Series: Basic Polynomial Regression

February 8, 2010
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R Tutorial Series: Basic Polynomial Regression

Often times, a scatterplot reveals a pattern that seems not so linear. Polynomial regression can be used to explore a predictor at different levels of curvilinearity. This tutorial will demonstrate how polynomial regression can be used in a hierarchical fashion to best represent a dataset in R.Tutorial FilesBefore we begin, you may want to download the sample...

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R Tutorial Series: Basic Polynomial Regression

February 8, 2010
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R Tutorial Series: Basic Polynomial Regression

Often times, a scatterplot reveals a pattern that seems not so linear. Polynomial regression can be used to explore a predictor at different levels of curvilinearity. This tutorial will demonstrate how polynomial regression can be used in a hierarchical fashion to best represent a dataset in R.Tutorial FilesBefore we begin, you may want to download the sample...

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R Tutorial Series: Hierarchical Linear Regression

January 15, 2010
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R Tutorial Series: Hierarchical Linear Regression

Regression models can become increasingly complex as more variables are included in an analysis. Furthermore, they can become exceedingly convoluted when things such as polynomials and interactions are explored. Thankfully, once the potential independe...

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Latin squares design in R

January 6, 2010
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Latin squares design in R

The Latin square design is used where the researcher desires to control the variation in an experiment that is related to rows and columns in the field.Remember that: * Treatments are assigned at random within rows and columns, with each treatment once per row and once per column. * There are equal numbers...

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Latin squares design in R

January 6, 2010
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Latin squares design in R

The Latin square design is used where the researcher desires to control the variation in an experiment that is related to rows and columns in the field.Remember that: * Treatments are assigned at random within rows and columns, with each treatment once per row and once per column. * There are equal numbers...

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Multilevel and Longitudinal Modeling in Stata

December 22, 2009
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For my "off-task" reading I recent perused an excellent book on multilevel and longitudinal modeling in Stata by Sophia Rabe-Hesketh and Anders Skrondal. The second edition (which I read) has been updated by including several chapters providing an over...

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got R? get social science for R!

December 19, 2009
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Drew Conway has a great list of 10 must-have R packages for social scientists. If you’re a social scientist (or really, any kind of scientist) who doesn’t use R, now is a great time to dive in and learn; there are tons of tutorials and guides out there (my favorite is Quick-R, which is incredibly

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R examine objects tutorial

November 21, 2009
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R examine objects tutorial

This article is quick concrete example of how to use the techniques from Survive R to lower the steepness of The R Project for Statistical Computing‘s learning curve (so an apology to all readers who are not interested in R). What follows is for people who already use R and want to achieve more controlRelated posts:

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