Publications by Yanchang Zhao
R Code Examples on Graphics
Some useful R code examples on graphics are: Learn R Toolkit: It contains PowerPoint slideshows, videos, R scripts and data files to help Excel users move up to R. R code examples are provided for panel charts, conditional format, dot plot, box plots with or without points, and fully annotated histogram charts. It is composed of 5 modules: Modu...
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Time Series Analysis and Mining with R
Time series data are widely seen in analytics. Some examples are stock indexes/prices, currency exchange rates and electrocardiogram (ECG). Traditional time series analysis focuses on smoothing, decomposition and forecasting, and there are many R functions and packages available for those purposes (see CRAN Task View: Time Series Analysis). Howev...
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Examples on Clustering with R
R code examples on various clustering techniques are available as “Clustering in R” in Chapter 4 of R & Bioconductor Manual by Thomas Girke, UC Riverside. It provides R examples on – Hierarchical Clustering, including tree cutting/coloring and heatmaps, – Bootstrap Analysis in Hierarchical Clustering, QT (quality threshold ) clustering, �...
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Slides of 10+ talks at R Users Groups
Links to slides of 10+ talks at R Users Groups in Australia are provided below. Slides of the talks are downloadable at the links, including R codes if any. MelbURN: Melbourne Users of R Network: Experiences with using R in credit risk R and industry: some (helpful) tips How to be smooth Creating R packages What my R code looks and feels like ...
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Datasets to Practice Your Data Mining
There are many datasets available online for free for research use. Some of them are listed below. – The R Datasets Package: There are around 90 datasets available in the package. Most of them are small and easy to feed into functions in R. See a list of data with the statement below: > library(help=”datasets”) – Frequent Itemset Mining D...
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Obama recruiting analysts and R is one preferred skill
Barack Obama is recruiting analysts for his 2012 re-election campaign. It is to analyze the campaign’s data to guide election strategy and develop quantitative, actionable insights that drive decision-making. R is mentioned as one of the tools to use. Analytics positions to recruit include: – Communications Analyst, – Digital Strategy Analy...
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Interactive charts with googleVis package and R
Examples at the link below illustrate interactive charts created with the googleVis package and R. http://code.google.com/p/google-motion-charts-with-r/wiki/GadgetExamples Some amazing features are: a motion chart shows the changes over time, an AnnotatedTimeLine shows zoom-in/zoom-out view of time series, a TreeMap supports drill-down and scor...
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R Cookbook with examples
An R Cookbook can be found at http://code.ca-net.org/R%20Cookbook. It is a short web document presenting dozens of examples on – Accessing Database with packages RSQLite, RMySQL, RdbiPgSQL and RODBC; – Reading and Writing Data; – Date/Time variable; – Graphics; – Spatial data; and – Debugging. Enjoy your data cooking with R. Regards Y...
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Help: stemming and stem completion with package tm in R
I came across a problem below when doing stemming and stem completion with package tm in R. Word “mining” was stemmed to “mine” with stemDocument(), and then completed to “miners”with stemCompletion(). However, I prefer to keep “mining” intact. For stemCompletion(), the default type of completion is “prevalent”, which takes th...
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Using Text Mining to Find Out What @RDataMining Tweets are About
This post shows an example on text mining of Twitter data with R packages twitteR, tm and wordcloud. Package twitteR provides access to Twitter data, tm provides functions for text mining, and wordcloud visualizes the result with a word cloud. Retrieving Text from Twitter Packages: twitteR: http://cran.r-project.org/bin/windows/contrib/r-old-rel...
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