Category: Analytics

Put your WordPress in the Sky

Heres something I am trying right now with WordPress and Clouds.(Provider –www.rightscale.com)

I will then try making R accessible from a web interface.

Segmenting Models : When and Why

Creating segmented models in SAS is quite easy, with a by group processing . It is less easy in other softwares , but that is understandable given that

the first generic rule of segmentation is

1) each segment has statistically similar characteristics .

2) different segments have statistically different characteristics .

This means that just using Proc freq to
check response rate versus
independent variable is not a good way
to check the level of difference.
Proc univariate with plot option and
a by group processing
is actually a better way to test out
because it is a combination of means ,
median analysis 
(measures of central value) but also
box plot ,normal distributions and standard deviations
(measures of dispersion).

Proc freq with cross tab is incredibly powerful to decide whether to create a model in the first place. But fine tuning of decisions on segments is better done with proc univariate. The SAS equivalent for clustering of course remains Proc Fastclus and family which will be dealt in a separate post.

(Note :lovely image that explains the above from Dr Ariel Shamir’s home page (he is a research expert on Visual Succinct Representation of Information   ————-from Israel, land of the brave and intelligent).

A Picture is truly worth a thousand words (or posts !).)

Legal Copyrights- Some history

Here is an interesting blog post on why software giants like google ,microsoft will be rich foroever. And ironically Microsoft has given away the maximum number of free programs, dlls, extensions,patches. When I mean free I mean really free, they did not sell your identity to advertisers .

”

Back in 1998, representatives of the Walt Disney Company came to Washington looking for help. Disney’s copyright on Mickey Mouse, who made his screen debut in the 1928 cartoon short “Steamboat Willie,” was due to expire in 2003, and Disney’s rights to Pluto, Goofy and Donald Duck were to expire a few years later.

Rather than allow Mickey and friends to enter the public domain, Disney and its friends – a group of Hollywood studios, music labels, and PACs representing content owners – told Congress that they wanted an extension bill passed.

Prompted perhaps by the Disney group’s lavish donations of campaign cash – more than $6.3 million in 1997-98, according to the nonprofit Center for Responsive Politics – Congress passed and President Clinton signed the Sonny Bono Copyright Term Extension Act.

The CTEA extended the term of protection by 20 years for works copyrighted after January 1, 1923. Works copyrighted by individuals since 1978 got “life plus 70” rather than the existing “life plus 50”. Works made by or for corporations (referred to as “works made for hire”) got 95 years. Works copyrighted before 1978 were shielded for 95 years, regardless of how they were produced.“

How to do Logistic Regression

Logistic regression is a widely used technique in database marketing for creating scoring models and in risk classification . It helps develop propensity to buy, and propensity to default scores (and even propensity to fraud ) .

This is more of a practical approach to make the model than a theory based approach.(I was never good at the theory 😉 )

If you need to do Logistic Regression using SPSS, a very good tutorial ia available here

http://www2.chass.ncsu.edu/garson/PA765/logistic.htm

(Note -Copyright 1998, 2008 by G. David Garson.
Last update 5/21/08.)

For SAS a very good tutorial is here –

SAS Annotated Output
Ordered Logistic Regression. UCLA: Academic Technology Services, Statistical Consulting Group.

from http://www.ats.ucla.edu/stat/sas/output/sas_ologit_output.htm (accessed July 23, 2007).

For R the documentation (note :Still searching for R ‘s Logistic Regression ) is here
http://lib.stat.cmu.edu/S/Harrell/help/Design/html/lrm.html
–

lrm(formula, data, subset, na.action=na.delete, method=”lrm.fit”, model=FALSE, x=FALSE, y=FALSE, linear.predictors=TRUE, se.fit=FALSE, penalty=0, penalty.matrix, tol=1e-7, strata.penalty=0, var.penalty=c(‘simple’,’sandwich’), weights, normwt, …)

For linear models in R –
http://datamining.togaware.com/survivor/Linear_Model0.html

An extremely good book if you want to work with R , and do not have time to learn it is to use the GUI
rattle and look at this book

http://datamining.togaware.com/survivor/Contents.html

SAS Fun: Sudoko

Here is a SAS program to help you beat others at Sudoko, and impress people. It was written by a chap named Ryan Howard in 2006, and I am thankful for him in allowing me in sharing this.You can let us know if you find a puzzle it could not solve , or if you tweak the program a bit. The code is pasted below.

Have fun !

And the SAS paper on this was at SAS Global Forum 2007- the resulting
paper, “SAS and Sudoku”, was written by Richard DeVenezia, John Gerlach,
Larry Hoyle, Talbot Katz and Rick Langston, and can be viewed at
http://www2.sas.com/proceedings/forum2007/011-2007.pdf.

(p.s. I haven’t tested this on WPS , they still dont have the SAS Macro language ,but let me know if you have any equivalent in SPSS or R 🙂   )

*=============================================================================;
* sudoku.sas                                                                  ;
* Written by: Ryan Howard                                                     ;
* Date: Sept. 2006                                                            ;
*-----------------------------------------------------------------------------;
* Summary: This program solves sudoku puzzles consisting of a 9X9 matrix.     ;
*-----------------------------------------------------------------------------;
* Upgrade Ideas:  1. Add a GUI to collect the input numbers and display output;
*                 2. Expand logic to work for 16X16 matrices                  ;
*=============================================================================;

title;
options nodate nonumber;

data _null_;

    *-----------------------------------------------------------------------------;
    * input  inital values for each cell from puzzle                              ;
    *-----------------------------------------------------------------------------;

    _1111=9; _1112=.; _1113=.;   _1211=.; _1212=.; _1213=.;   _1311=1; _1312=.; _1313=.;
    _1121=5; _1122=.; _1123=.;   _1221=.; _1222=6; _1223=.;   _1321=.; _1322=4; _1323=2;
    _1131=.; _1132=.; _1133=.;   _1231=7; _1232=1; _1233=.;   _1331=5; _1332=.; _1333=.;

    _2111=.; _2112=.; _2113=2;   _2211=.; _2212=.; _2213=.;   _2311=.; _2312=1; _2313=.;
    _2121=.; _2122=3; _2123=.;   _2221=.; _2222=.; _2223=.;   _2321=2; _2322=9; _2323=.;
    _2131=.; _2132=7; _2133=.;   _2231=.; _2232=.; _2233=6;   _2331=.; _2332=.; _2333=3;

    _3111=.; _3112=2; _3113=.;   _3211=.; _3212=.; _3213=8;   _3311=.; _3312=.; _3313=.;
    _3121=.; _3122=.; _3123=4;   _3221=5; _3222=.; _3223=.;   _3321=.; _3322=.; _3323=.;
    _3131=.; _3132=.; _3133=.;   _3231=.; _3232=3; _3233=.;   _3331=8; _3332=.; _3333=9;

    %macro printmatrix;
    *----------------------------------------------------------------;
    * print the result matrix                                        ;
    *----------------------------------------------------------------;
       *---------------------------------------------------;
       * Assign column positions for printing matrix       ;
       *---------------------------------------------------;
       c1=1;
       c2=10;
       c3=20;
 Continue reading "SAS Fun: Sudoko"

Cloud Computing across LAN’s ?

The concept of cloud computing is interesting and actually quite old. It lacked major backing till Google came along and is now increasingly seen as the alternative to PC (given that other alternatives like Tablet PC came and went).

This diagram and definition is from Wikipedia of course ”

Cloud computing refers to computing resources being accessed which are typically owned and operated by a third-party provider on a consolidated basis in Data Center locations. Consumers of cloud computing services purchase computing capacity on-demand and are not generally concerned with the underlying technologies used to achieve the increase in server capability. There are however increasing options for developers that allow for platform services in the cloud where developers do care about the underlying technology.”

What prevents local area networks from enforcing clouds beats me. Put all the apps and ALL the storage on the server.Since most PC OEMS insist on their standard 80 gb hard disk configuration, the IT team of a company has to work harder to enforce it, but once done – They have lower tickets to attend to. Just put thin shell ubuntu PC’s with open office on each local machine. This also makes compliance and productivity tracking much easier to do- just check the server logs. Bottlenecks of course remain that IT Compliance in companies rarely seeks to maximize business value, thus ensuring they are the first to be transferred  to other teams or downsized in downturns as a cost unit not as a core unit.

You can also try Google Apps for enterprise for such initiatives. The software is now ready which wasnt the case a few years back.