Blog Archives

Easily generate correlated variables from any distribution

February 27, 2014
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Easily generate correlated variables from any distribution

In this post I will demonstrate in R how to draw correlated random variables from any distributionThe idea is simple.  1. Draw any number of variables from a joint normal distribution. 2. Apply the univariate normal CDF of variables to derive pro...

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Using MongoHQ to build a Shiny Hit Counter

February 6, 2014
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In serveral previous posts I have posted shiny applications which temporarily store data on shiny servers such as hit counters or the survey tool which I created,  These do not work in the long term since shiny will restart its servers without war...

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Stick Figure Function Fun – R

January 31, 2014
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Stick Figure Function Fun – R

I have created a stick figure generating function for the purposes of adding a human figure as a demonstration of scale to some of my graphs as well as potentially emoticons to my shiny/concerto applications.You can change basic graphing parameters li...

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Incidental Parameters Problem with Binary Response Data and Unobserved Individual Effects

December 5, 2013
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Incidental Parameters Problem with Binary Response Data and Unobserved Individual Effects

It is a well known problem that in some models as the number of observations becomes large, econometric estimators fail to converge on consistent estimators.  The leading case of this is when estimating a binary response model with panel data with...

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Unobserved Effects With Panel Data

December 4, 2013
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It is common for researchers to be concerned about unobserved effects being correlated with observed explanatory variables.For instance, if we were curious about the effect of meditation on emotional stability we may be concerned that there might be so...

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More Explorations with catR

December 1, 2013
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More Explorations with catR

# For the purposes of simulating computerized adaptive tests# the R package catR is unparallelled. # catR is an excellent tool for students who are curious about# how a computerized adaptive test might work. It is also useful# for testing companie...

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Results of an Informal Survey of R users

November 22, 2013
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Results of an Informal Survey of R users

# This post does some basic correlation analysis between responses# to the survey I recently released through R Shiny at:http://www.econometricsbysimulation.com/2013/11/Shiny-Survey-Tool.html # I have saved the data from the survey after completin...

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A Survey Tool Designed Entirely in Shiny Surveying Users of R

November 19, 2013
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A Survey Tool Designed Entirely in Shiny Surveying Users of R

I have written a very basic survey tool built entirely in the Shiny package of R.  I hope the tool is useful.  Modifying the survey for your own purposes is trivially easy (I hope).I have not commented my code so it is pretty messy right now....

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Alpha testing shinyapps.io – first impressions

November 17, 2013
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Alpha testing shinyapps.io – first impressions

ShinyApps.io is a new server which is currently in alpha testing to host Shiny applications.  It is being designed by the RStudio team and provides some distinct features different from that of the ShinyApps.io is intended for larger applications ...

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A Shiny App for Experimenting with Dynamic Programming

November 15, 2013
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A Shiny App for Experimenting with Dynamic Programming

This post demonstrates the dynamics involved in a susceptible, infected, and recovering (SIR) model previous post for the model.  The shiny ui and server code can be found on GitHub.of dynamic programming. As a dynamic infection model, I find it p...

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