Tag: ajay

Interview Jeff Allen Trestle Technology #rstats #rshiny

Here is an interview with Jeff Allen who works with R and the new package Shiny in his technology startup. We featured his RGL Demo in our list of Shiny Demos- here

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Ajay- Describe how you started using R. What are some of the benefits you noticed on moving to R?

Jeff- I began using R in an internship while working on my undergraduate degree. I was provided with some unformatted R code and asked to modularize the code then wrap it up into an R package for distribution alongside a publication.

To be honest, as a Computer Science student with training more heavily emphasizing the big high-level languages, R took some getting used to for me. It wasn’t until after I concluded that initial project and began using R to do my own data analysis that I began to realize its potential and value. It was the first scripting language which really made interactive use appealing to me — the experience of exploring a dataset in R was unlike anything Continue reading “Interview Jeff Allen Trestle Technology #rstats #rshiny”

Talking on Big Data Analytics

I am going  being sponsored to a Government of India sponsored talk on Big Data Analytics at Bangalore on Friday the 13 th of July. If you are in Bangalore, India you may drop in for a dekko. Schedule and Abstracts (i am on page 7 out 9) .

Your tax payer money is hard at work- (hassi majak only if you are a desi. hassi to fassi.)

13 July 2012 (9.30 – 11.00 & 11.30 – 1.00)
Big Data Big Analytics
The talk will showcase using open source technologies in statistical computing for big data, namely the R programming language and its use cases in big data analysis. It will review case studies using the Amazon Cloud, custom packages in R for Big Data, tools like Revolution Analytics RevoScaleR package, as well as the newly launched SAP Hana used with R. We will also review Oracle R Enterprise. In addition we will show some case studies using BigML.com (using Clojure) , and approaches using PiCloud. In addition it will showcase some of Google APIs for Big Data Analysis.

Lastly we will talk on social media analysis ,national security use cases (i.e. cyber war) and privacy hazards of big data analytics.

Schedule

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Abstracts

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Data Mining Music

AA classic paper by Donald E Knuth (creator  of Tex) on the information complexity of songs can help listeners of music with an interest in analytics. This paper is a classic and dates from 1985 but is pertinent even today.

 

Knuth song complexity

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R for Business Analytics- Book by Ajay Ohri

So the cover art is ready, and if you are a reviewer, you can reserve online copies of the book I have been writing for past 2 years. Special thanks to my mentors, detractors, readers and students- I owe you a beer!

You can also go here-

http://www.springer.com/statistics/book/978-1-4614-4342-1

 

R for Business Analytics

R for Business Analytics

Ohri, Ajay

2012, 2012, XVI, 300 p. 208 illus., 162 in color.

Hardcover
Information

ISBN 978-1-4614-4342-1

Due: September 30, 2012

(net)

approx. 44,95 €
  • Covers full spectrum of R packages related to business analytics
  • Step-by-step instruction on the use of R packages, in addition to exercises, references, interviews and useful links
  • Background information and exercises are all applied to practical business analysis topics, such as code examples on web and social media analytics, data mining, clustering and regression models

R for Business Analytics looks at some of the most common tasks performed by business analysts and helps the user navigate the wealth of information in R and its 4000 packages.  With this information the reader can select the packages that can help process the analytical tasks with minimum effort and maximum usefulness. The use of Graphical User Interfaces (GUI) is emphasized in this book to further cut down and bend the famous learning curve in learning R. This book is aimed to help you kick-start with analytics including chapters on data visualization, code examples on web analytics and social media analytics, clustering, regression models, text mining, data mining models and forecasting. The book tries to expose the reader to a breadth of business analytics topics without burying the user in needless depth. The included references and links allow the reader to pursue business analytics topics.

 

This book is aimed at business analysts with basic programming skills for using R for Business Analytics. Note the scope of the book is neither statistical theory nor graduate level research for statistics, but rather it is for business analytics practitioners. Business analytics (BA) refers to the field of exploration and investigation of data generated by businesses. Business Intelligence (BI) is the seamless dissemination of information through the organization, which primarily involves business metrics both past and current for the use of decision support in businesses. Data Mining (DM) is the process of discovering new patterns from large data using algorithms and statistical methods. To differentiate between the three, BI is mostly current reports, BA is models to predict and strategize and DM matches patterns in big data. The R statistical software is the fastest growing analytics platform in the world, and is established in both academia and corporations for robustness, reliability and accuracy.

Content Level » Professional/practitioner

Keywords » Business Analytics – Data Mining – Data Visualization – Forecasting – GUI – Graphical User Interface – R software – Text Mining

Related subjects » Business, Economics & Finance – Computational Statistics – Statistics

TABLE OF CONTENTS

Why R.- R Infrastructure.- R Interfaces.- Manipulating Data.- Exploring Data.- Building Regression Models.- Data Mining using R.- Clustering and Data Segmentation.- Forecasting and Time-Series Models.- Data Export and Output.- Optimizing your R Coding.- Additional Training Literature.- Appendix

Random Sampling a Dataset in R

A common example in business  analytics data is to take a random sample of a very large dataset, to test your analytics code. Note most business analytics datasets are data.frame ( records as rows and variables as columns)  in structure or database bound.This is partly due to a legacy of traditional analytics software.

Here is how we do it in R-

• Refering to parts of data.frame rather than whole dataset.

Using square brackets to reference variable columns and rows

The notation dataset[i,k] refers to element in the ith row and jth column.

The notation dataset[i,] refers to all elements in the ith row .or a record for a data.frame

The notation dataset[,j] refers to all elements in the jth column- or a variable for a data.frame.

For a data.frame dataset

> nrow(dataset) #This gives number of rows

> ncol(dataset) #This gives number of columns

An example for corelation between only a few variables in a data.frame.

> cor(dataset1[,4:6])

Splitting a dataset into test and control.

ts.test=dataset2[1:200] #First 200 rows

ts.control=dataset2[201:275] #Next 75 rows

• Sampling

Random sampling enables us to work on a smaller size of the whole dataset.

use sample to create a random permutation of the vector x.

Suppose we want to take a 5% sample of a data frame with no replacement.

Let us create a dataset ajay of random numbers

ajay=matrix( round(rnorm(200, 5,15)), ncol=10)

#This is the kind of code line that frightens most MBAs!!

Note we use the round function to round off values.

ajay=as.data.frame(ajay)

 nrow(ajay)

[1] 20

> ncol(ajay)

[1] 10

This is a typical business data scenario when we want to select only a few records to do our analysis (or test our code), but have all the columns for those records. Let  us assume we want to sample only 5% of the whole data so we can run our code on it

Then the number of rows in the new object will be 0.05*nrow(ajay).That will be the size of the sample.

The new object can be referenced to choose only a sample of all rows in original object using the size parameter.

We also use the replace=FALSE or F , to not the same row again and again. The new_rows is thus a 5% sample of the existing rows.

Then using the square backets and ajay[new_rows,] to get-

b=ajay[sample(nrow(ajay),replace=F,size=0.05*nrow(ajay)),]

 

You can change the percentage from 5 % to whatever you want accordingly.

Using Google Adwords to target Vic Gundotra and Matt Cutts stochastically

Over the Christmas break, I created a Google Adwords campaign using the $100 credit generously given by Google. I did it using my alumni id, even though I have a perfectly normal gmail id. I guess if Google allows me to use the credit on any account- well I will take it. and so a free experiment was borne.

But whom to target -with Google- but Google itself. It seemed logical

So I created a campaign for the names of prominent Googlers  (from a list of Google + at https://plus.google.com/103399926392582289066/posts/LX4g7577DqD ) and limited the ad location to Mountain View, California.

NULL HYPOTHESIS- People who are googled a lot from within the office are either popular or just checking themselves.

Since Google’s privacy policy is great, has been now shown billions of times, well I guess what’s a little ad targetting between brother geeks. Right?

My ad was-

Hire Ajay Ohri
He is
Awesome
linkedin.com/in/ajayohri 

or see screenshot below.

Here are the results-88 clicks and 43000 impressions (and 83$ of Google’s own money)

clearly Vic Gundotra is googled a lot within Mountain View, California. Does He Google himself.

so is Matt Cutts. Does HE Google himself or does he get elves to help him.

to my disappointment not many people clicked my LI offer, I am still blogging

and there were few clicks on Marissa Myers. Why Google her when she is right down the corridor.

The null hypothesis is thus rejected. Also most clicks were from display and not from search.

I need to do something better to do with Christmas break this year. I still got a credit of 16$ left.

 

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