1766 search results for "ggplot2"

Recovering Marginal Effects and Standard Errors of Interactions Terms Pt. II: Implement and Visualize

March 9, 2012
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Recovering Marginal Effects and Standard Errors of Interactions Terms Pt. II: Implement and Visualize

In the last post I presented a function for recovering marginal effects of interaction terms. Here we implement the function with simulated data and plot the results using ggplot2.       #---Simulate Data and Fit a linear model with an...

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Recovering Marginal Effects and Standard Errors of Interactions Terms Pt. II: Implement and Visualize

March 9, 2012
By
Recovering Marginal Effects and Standard Errors of Interactions Terms Pt. II: Implement and Visualize

In the last post I presented a function for recovering marginal effects of interaction terms. Here we implement the function with simulated data and plot the results using ggplot2.       #---Simulate Data and Fit a linear model with an...

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Mining Twitter for consumer attitudes towards hotels

March 9, 2012
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Mining Twitter for consumer attitudes towards hotels

Couple of months back I read Jeffrey Breen’s presentation on mining Twitter for consumer attitudes towards airlines, so I was just curious how it would look if I estimate the sentiment toward major hotels. So here it is: # load twitter library > library(twitteR) # search for all the hilton tweets > hilton.tweets=searchTwitter('@hilton',n=1500) > length(hilton.tweets)

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Benford’s Law after converting count data to be in base 5

March 8, 2012
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Benford’s Law after converting count data to be in base 5

Firstly, I know nothing about election fraud – this isn’t a serious post. But, I do like to do some simple coding. Ben Goldacre posted on using Benford’s Law to look for evidence of Russian election fraud. Then Richie Cotton did the same, but using R. Commenters on both sites suggested that as the data

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A plot of my citations in Google Scholar vs. Web of Science

March 8, 2012
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A plot of my citations in Google Scholar vs. Web of Science

There has been some discussion about whether Google Scholar or one of the proprietary software companies numbers are better for citation counts. I personally think Google Scholar is better for a number of reasons: Higher numbers, but consistently/a...

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How Not To Draw a Probability Distribution

March 7, 2012
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How Not To Draw a Probability Distribution

If I google for “probability distribution” I find the following extremely bad picture: It’s bad because it conflates ideas and oversimplifies how variable probability distributions can generally be. Most distributions are not unimodal. Most dist...

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Philadelphia Schools

March 7, 2012
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Philadelphia Schools

I'm on spring break, and yesterday I took some time to check off some items on my to-do list, namely:Start getting acquainted with all the new features of ggplot2 .Get a handle on dealing with geographic data in R.I've done some furtive geographic...

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Setting Up and Customizing R

March 7, 2012
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For the longest time I resisted customizing R for my particular environment. My philosophy has been that each R script for each separate analysis I do should be self contained such that I can rerun the script from top to bottom on any machine and get the same results. This being said, I have now

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Why an inverse-Wishart prior may not be such a good idea

March 7, 2012
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Why an inverse-Wishart prior may not be such a good idea

While playing around with Bayesian methods for random effects models, it occured to me that inverse-Wishart priors can really bite you in the bum. Inverse Wishart-priors are popular priors over covariance functions. People like them priors because they are conjugate to a Gaussian likelihood, i.e, if you have data with each : so that the

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Airline Fares Decreasing Steadily

March 5, 2012
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Airline Fares Decreasing Steadily

Description: Yearly average airline fare since 1995. Data: http://www.bts.gov/ Analysis: When taking the average price of domestic airline fares, there is a clear trend indicating that flying is becoming more affordable - when adjusted for infl...

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