185 search results for "heatmap"

Color extraction with R

March 4, 2015
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Color extraction with R

Given all the attention the internet has given to the colors of this dress, I thought it would be interesting to look at the capabilities for extracting colors in R. R has a number of packages for importing images in various file formats, including PNG, JPG, TIFF, and BMP. (The readbitmap package works with all of these.) In each...

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Eight New Ideas From Data Visualization Experts

February 12, 2015
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Eight New Ideas From Data Visualization Experts

This post summarizes and visualizes eight key ideas we’ve heard from data visualization experts. Check out our first Case Study to learn more about using Plotly Enterprise on-premise, on your servers. To get started on free online graphing like in this post, check out our tutorials. Make Interactive Graphs Pictures of graphs in PowerPoints, dashboards, and emails can...

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Some Applications of Item Response Theory in R

January 11, 2015
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Some Applications of Item Response Theory in R

The typical introduction to item response theory (IRT) positions the technique as a form of curve fitting. We believe that a latent continuous variable is responsible for the observed dichotomous or polytomous responses to a set of items (e.g., multipl...

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Top 77 R posts for 2014 (+R jobs)

January 7, 2015
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Top 77 R posts for 2014 (+R jobs)

R-bloggers.com is 5 years old this month! In celebration, this post share links to the top 77 most read R posts of 2014 (+stats on R-bloggers, + top R jobs for the beginning of 2015)

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Mapping IPv4 Address (with Hilbert curves) in R

January 2, 2015
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Mapping IPv4 Address (with Hilbert curves) in R

While there’s an unholy affinity in the infosec commuinty with slapping IPv4 addresses onto a world map, that isn’t the only way to spatially visualize IP addresses. A better approach (when tabluation with bar charts, tables or other standard visualization techniques won’t do) is to map IPv4 addresses into Hilbert space-filling curve. You can get a good feel...

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Contextual Measurement Is a Game Changer

December 22, 2014
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Contextual Measurement Is a Game Changer

Adding a context can change one's frame of reference:Are you courteous? Are you courteous at work? Decontextualized questions tend to activate a self-presentation strategy and retrieve memories of past positioning of oneself (impression manag...

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A New Volatility Strategy, And A Heuristic For Analyzing Robustness

December 4, 2014
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A New Volatility Strategy, And A Heuristic For Analyzing Robustness

This post is motivated by a discussion that arose when I tested a strategy by Frank of Trading The Odds … Continue reading →

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Trading The Odds Volatility Risk Premium: Addressing Data Mining and Curve-Fitting

November 19, 2014
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Trading The Odds Volatility Risk Premium: Addressing Data Mining and Curve-Fitting

Several readers, upon seeing the risk and return ratio along with other statistics in the previous post stated that the … Continue reading →

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Introducing Stepwise Correlation Rank

October 27, 2014
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Introducing Stepwise Correlation Rank

So in the last post, I attempted to replicate the Flexible Asset Allocation paper. I’d like to offer a thanks … Continue reading →

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Modeling Plenitude and Speciation by Jointly Segmenting Consumers and their Preferences

October 21, 2014
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Modeling Plenitude and Speciation by Jointly Segmenting Consumers and their Preferences

In 1993, when music was sold in retail stores, it may have been informative to ask about preference across a handful of music genre. Today, now that the consumer has seized control and the music industry has responded, the market has exploded into more...

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