168 search results for "iris"

R framework with Object-Oriented Programming

February 13, 2014
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Data analysis deals with different kinds of data. For instance we can have supermarket sales with - a transactional table, with customer ID, item ID, date of purchase - an item table, with the item ID and its price - … Continue reading →

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Self-Organising Maps for Customer Segmentation using R

February 3, 2014
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Self-Organising Maps for Customer Segmentation using R

Self-Organising Maps (SOMs) are an unsupervised data visualisation technique that can be used to visualise high-dimensional data sets in lower (typically 2) dimensional representations. In this post, we examine the use of R to create a SOM for customer segmentation. The figures shown here used use the 2011 Irish Census information for the greater Dublin

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Topological Data Analysis with R

January 16, 2014
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Topological Data Analysis with R

by Joseph Rickert When I was in graduate school in the mid '70s Mathematics departments were still under the spell of abstraction for its own sake. At that time, Algebraic Topology which uses concepts from Abstract Algebra to study topological spaces was a major gateway to the realm of abstraction. On my first visit, it was not at all...

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Computing and visualizing LDA in R

January 15, 2014
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Computing and visualizing LDA in R

As I have described before, Linear Discriminant Analysis (LDA) can be seen from two different angles. The first classify a given sample of predictors to the class with highest posterior probability . It minimizes the total probability of misclassification. To compute it uses Bayes’ rule and assume that follows a Gaussian distribution with class-specific mean

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Analemma graphs

December 27, 2013
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Analemma graphs

Continuing on the theme of solar angles, the code given below produces an analemma diagram similar to that of Lynch (2012, figure 2). 1 2 3 4 5 6 7 8 9 10 library(oce) loc <- list(lon=-0.0015, lat=51.4778) # Greenwich Observatory t <- seq.POSIXt(as.POSIXct("2014-01-01 12:00:00", tz="UTC"), as.POSIXct("2015-01-01...

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New package: jsonlite. A smart(er) JSON encoder/decoder.

December 6, 2013
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New package: jsonlite. A smart(er) JSON encoder/decoder.

This week we released a new package on CRAN: jsonlite. This package is a fork of RJSONIO by Duncan Temple Lang and builds on the same parser, but uses a different mapping between R objects and JSON data. The package vignette goes in great detail and has many examples on...

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New package: jsonlite. A smart(er) JSON encoder/decoder.

December 6, 2013
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New package: jsonlite. A smart(er) JSON encoder/decoder.

This week we released a new package on CRAN: jsonlite. This package is a fork of RJSONIO by Duncan Temple Lang and builds on the same parser, but uses a different mapping between R objects and JSON data. The package vignette goes in great detail and has many examples on...

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Computing and visualizing PCA in R

November 28, 2013
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Computing and visualizing PCA in R

Following my introduction to PCA, I will demonstrate how to apply and visualize PCA in R. There are many packages and functions that can apply PCA in R. In this post I will use the function prcomp from the stats package. I will also show how to visualize PCA in R using Base R graphics.

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Double Box Plot package boxplotdbl 1.2.0 released

November 23, 2013
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Double Box Plot package boxplotdbl 1.2.0 released

This article describes changes from the first release on March 2013, including changes from the beta release of package boxplotdbl. New features Newly supported arguments: col COLOR.SHEER factor.labels draw.legend shading … Continue reading →

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Beads Summary Plot of Ranges for R

November 12, 2013
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Beads Summary Plot of Ranges for R

The beadsplot function is designed for a data frame with a factor column and many observation columns.  This function summarize the data visually.  The builtin iris data is suitable to … Continue reading →

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