2376 search results for "ggplot"

‘Tis the Season for September Bearishness?

August 22, 2013
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‘Tis the Season for September Bearishness?

Is September Bearish? Traders love discussing seasonality, and September declines in US equity markets are a favorite topic. Historically September has underperformed every other month of the year, offering a mean return of -.56% on the S&P 500 index from 1950 to 2012; 54% of Septembers were bearish over the same period – more than any other month. Empirically, September...

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Exploring the robustness of Bayes Factors: A convenient plotting function

August 22, 2013
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Exploring the robustness of Bayes Factors: A convenient plotting function

One critique frequently heard about Bayesian statistics is the subjectivity of the assumed prior distribution. If one is cherry-picking a prior, of course the posterior can be tweaked, especially when only few data points are at hand. For example, see the Scholarpedia article on Bayesian statistics: In the uncommon situation that the data are extensive

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Downloading and Analyzing CD1025’s Playlist

August 20, 2013
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Downloading and Analyzing CD1025’s Playlist

CD1025 is an “alternative” radio station here in Columbus. They are one of the few remaining radio stations that are independently owned and they take great pride in it. For data nerds like me, they also put a real time list of recently played songs on their website. The page has the most recent 50 songs played,...

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Downloading and Analyzing CD1025’s Playlist

August 19, 2013
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Downloading and Analyzing CD1025’s Playlist

CD1025 is an “alternative” radio station here in Columbus. They are one of the few remaining radio stations that are independently owned and they take great pride in it. For data nerds like me, they also put a real time list of recently played songs on their website. The page has the most recent 50 songs played,...

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Is the Tax Code the longest Title?

August 19, 2013
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Is the Tax Code the longest Title?

  Last week, I shared that Dan Katz and I had finally published a draft of our paper, Measuring the Complexity of the Law: The U.S. Code.  We’d previewed this research on Computational Legal Studies years ago.  Since then, we’ve received great… Read more ›

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#21 – Find significant relationships in data with a CoCo Matrix

August 19, 2013
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#21 – Find significant relationships in data with a CoCo Matrix

The CoCo Matrix (correlation coefficient matrix) is a script for R that takes a table headed with multiple variables and calculates the correlation coefficients between each of the variables, determines which are statistically significant, and represents them visually in a grid-plot. I created the CoCo Matrix to cross correlate a table with a large number of

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Endogenous Spatial Lags for the Linear Regression Model

August 18, 2013
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Endogenous Spatial Lags for the Linear Regression Model

Over the past number of years, I have noted that spatial econometric methods have been gaining popularity. This is a welcome trend in my opinion, as the spatial structure of data is something that should be explicitly included in the empirical modelling procedure. Omitting spatial effects assumes that the location co-ordinates for observations are unrelated

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Clarifying vague interactions

August 18, 2013
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Clarifying vague interactions

For some reason, authors occasionally present linear model results with vague or unintelligible interaction effects. One way to be vague when presenting interaction effects is to provide only a table of model coefficients, including no information on the range of covariate values observed, and no plots to aid in interpretation. Here’s an example: Suppose you have discovered a statistically significant...

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Negative Payments in Local Spending Data

August 17, 2013
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Negative Payments in Local Spending Data

In anticipation of a new R library from School of Data data diva @mihi_tr that will wrap the OpenSpending API and providing access to OpenSpending.org data directly from within R, I thought I’d start doodling around some ideas raised in Identifying Pieces in the Spending Data Jigsaw. In particular, common payment values, repayments/refunds and “balanced

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Working with climate data from the web in R

August 17, 2013
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Working with climate data from the web in R

I recently attended ScienceOnline Climate, a conference in Washington, D.C. at AAAS. You may have heard of the ScienceOnline annual meeting in North Carolina - this was one of their topical meetings focused on Climate Change. I moderated a session on working with data from the web in R, focusing on climate data. Search Twitter for...

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