# Monthly Archives: April 2014

## Twitter sentiment analysis with R

Recently I designed a relatively simple code in R to analyze the content of Twitter posts by using the categories identified as positive, negative and neutral. The idea of processing tweets is based on a presentation http://www.slideshare.net/ajayohri/twitter-analysis-by-kaify-rais. The algorithm evaluates tweets based on the number of positive and negative words in the tweet. The words in the tweet correspond with the words... Read More »

## What Can Go Wrong: My Favorite Example

April 28, 2014
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I’m one of many who bemoan the fact that statistics is typically thought of as — alas, even taught as — a set of formula plugging methods. One enters one’s data, turns the key, and the proper answers pop out. This of course is not the case at all, and arguably statistics is as much

## What Can Go Wrong: My Favorite Example

April 28, 2014
By

I’m one of many who bemoan the fact that statistics is typically thought of as — alas, even taught as — a set of formula plugging methods. One enters one’s data, turns the key, and the proper answers pop out. This of course is not the case at all, and arguably statistics is as much

April 27, 2014
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If you love knitr and rstudio and use them to produce long reports, you probably know that you can produce a table of contents in your html (and pdf) documents. In the newer rstudio (Version 0.98.801 or later) you do it by requesting a toc in the doc header, something like this. title: "cssTest" output:

## Calendar Strategy: Month End

April 27, 2014
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Calendar Strategy is a very simple strategy that buys an sells at the predetermined days, known in advance. Today I want to show how we can easily investigate performance at and around Month End days. First let’s load historical prices for SPY from Yahoo Fiance and compute SPY perfromance at the month-ends. I.e. strategy will

## ggplot with a highcharts taste

April 27, 2014
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Update 2015-11-07: This is modification from an old post. Finnaly I made a pull request and was accepted by Jeffrey Arnold At work I use ggplot2 almost for everything. I really like the mid term between high level (highcharts) and low-level (like d3 for example). The deafult theme for ggplot it’s good, and really good if you compare with...

## Introducing Statwing

April 27, 2014
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Recently, Greg Laughlin, the founder of a new statistical software called Statwing, let me try his product for free. I happen to like free things very much (the college student is strong within me) so I gave it a try. I mostly like how easy it is to use: For instance, to relate two attributes

## Project Tycho, Correlation between states

April 27, 2014
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In this fourth post on Measles data I want to have a look at correlation between states. As described before, the data is from Project Tycho, which contains data from all weekly notifiable disease reports for the United States dating back to 1888...

## Le Monde puzzle [#869]

April 26, 2014
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A Le Monde mathematical puzzle once again in a Sudoku mode: In an nxn table, all integers between 1 and n appear n times. If max denotes the maximum over the numbers of different integers on all rows and columns,  what is the minimum value of max when n=7? when n=11? I tried to solve

## What If You Dig A Hole Through The Earth?

April 26, 2014
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It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn’t feel like a giant. I felt very, very small (Neil Armstrong) Where would you come out if you dig a hole straight