1382 search results for "excel"

Statistics on Microsoft Excel

February 6, 2007
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Here is an interesting document on problems of using Microsoft Excel for statistical analysis. http://gcrc.ucsd.edu/biostatistics/Excel.pdf Technorati Tags: statistics, excel, microsoft

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New packages for reading data into R — fast

April 10, 2015
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Hadley Wickham and the RStudio team have created some new packages for R, which will be very useful for anyone who needs to read data into R (that is, everyone). The readr package provides functions for reading text data into R, and the readxl package provides functions for reading Excel spreadsheet data into R. Both are much faster than...

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Recreating the vaccination heatmaps in R

April 9, 2015
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Recreating the vaccination heatmaps in R

In February the WSJ graphics team put together a series of interactive visualisations on the impact of vaccination that blew up on twitter and facebook, and were roundly lauded as great-looking and effective dataviz. Some of these had enough data available to look … Continue reading →

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Association Rules and Market Basket Analysis with R

April 8, 2015
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In today's data-oriented world, just about every retailer has amassed a huge database of purchase transaction. Each transaction consists of a number of products that have been purchased together. A natural question that you could answer from this database is: What products are typically purchased together? This is called Market Basket Analysis (or Affinity Analysis). A closely related question...

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Standardising Function Names in R

March 31, 2015
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Standardising Function Names in R

The renamer Package Tired of the disparate naming systems in R? Then this is the package for you. Installing the package The package is located in my drat. To install install.packages("renamer", repos="http://csgillespie.github.io/drat", type="source") or if you have drat installed drat::addRepo("csgillespie") install.packages("renamer", type="source") The source is available on my github page Example: The CamelCaseR If have an

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Factor Evaluation in Quantitative Portfolio Management

March 23, 2015
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Factor Evaluation in Quantitative Portfolio Management

When it comes to managing a portfolio of stocks versus a benchmark the problem is very different from defining an absolute return strategy. In the former one has to hold more stocks than in the later where no stocks at all can be held  if there is not good enough opportunity.  The reason for that is the tracking error. This

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PMRetract: PubMed retraction reporting rewritten as an interactive RMarkdown document

March 22, 2015
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PMRetract: PubMed retraction reporting rewritten as an interactive RMarkdown document

Back in 2010, I wrote a web application called PMRetract to monitor retraction notices in the PubMed database. It was written primarily as a way for me to explore some technologies: the Ruby web framework Sinatra, MongoDB (hosted at MongoHQ, now Compose) and Heroku, where the app was hosted. I automated the update process using

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Parsing Dates and Times

March 21, 2015
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Parsing Dates and Times

Motivation R has excellent for dates and times via the built-in Date and POSIXt classes. Their usage, however, is not always as straightforward as one would want. Certain conversions are more cumbersome than we would like: while as.Date("2015-03-22"), would it not be nice if as.Date("20150322") (a format often used in logfiles) also worked, or for that matter as.Date(20150322L) using an integer variable, or...

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Fixing Colors & Proportions in Jerusalem Post Election Graphics

March 20, 2015
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Fixing Colors & Proportions in Jerusalem Post Election Graphics

Vis expert Naomi Robbins did an excellent critique of the graphics that went along with an article on Israeli election in the Jerusalem Post. Non-uniform and color-blind-unfriendly categorical colors and disproportionate arc sizes are definitely three substantial issues in that series of visualizations. We can rectify all of them with two new packages of mine:

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New Online Tool for Seasonal Adjustment

March 20, 2015
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New Online Tool for Seasonal Adjustment

A new website is showcasing the use of seasonal and allows for online seasonal adjustment of time series.

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