stattler.com - statistics blog and discussions

Introduction to Statistics (পরিসংখ্যান পরিচিতি) offered through shikkhok.com

enayet — Wed, 07 Nov 2012 18:31:08 +0000

I am excited to announce that I am offering a course on introductory statistics. The course will be offered through shikkhok.com-- an open knowledge/learning platform in Bangla language.

An introductory lecture posted on shikkhok.com website outlines the course objective. A few real life examples where statistical tools are being used have been discussed.

Survey Data Analysis with Stata: Part 2

clifford — Fri, 20 Jul 2012 15:38:33 +0000

Complex survey analysis with examples. Use of svyset with brr method for variance estimation with Stata 12. Example of how to merge survey data with the replicate weight data to create a merged data file.

Survey Data Analysis with Stata: Part 1

clifford — Tue, 01 May 2012 15:42:17 +0000

A complex survey involves collection of data in stages (single-stage or multiple-stage designs), drawn from different strata or clusters of the population. We use Stata statistical package for analyzing survey data. Stata has a powerful set of tools to do survey analyses that takes into account the multi-stage and/or clustering nature of the data.

14 PhD positions in Statistics in Europe

enayet — Thu, 29 Mar 2012 13:18:11 +0000

There are fourteen (14) open PhD positions in methodological research in diagnostic/prognostic and therepeutic studies and meta analysis. The positions are available at different sites accross Europe. Open to any nationals. Deadline is April 25, 2012, position begins in May or September 2012.

Western invites you

azaz — Sat, 10 Mar 2012 03:25:00 +0000

It took me a little while to write something about admissions into a Canadian university, but I won’t leave the opportunity to share my opinion on questions that I have encountered an uncountable number of times. The purpose of this article is to share with the interested students about my school—Western University, and the city of London, Ontario--the city I am currently living in. But before that, let me tell you how to become successful in getting admission into a graduate school in Canada.

Testing equality of two population variances using Stata

enayet — Fri, 02 Mar 2012 20:04:52 +0000

I was asked if we can do the test of equality of two population variances using Stata. Well, I did not have to do it myself ever, but yes, it is possible to do it. Here is an example. I've just made-up the data to show the procedures.

Suppose we have the following data where the variables may represent two independent samples taken from normally distributed populations. And we want to test if the population variances of the two populations are the same. We will use the sample variances to do the testing.

Poisson approximation of binomial probabilities

enayet — Thu, 01 Mar 2012 21:25:09 +0000

This is yet another experiment to see how good is the approximation of binomial probability when we use Poisson and normal distributions for scenarios with large $n$, and $p$ close to zero or one.

Consider a problem where the random variable $X$ follows a binomial distribution with a known probability of success $p$, and number of trials $n$. If $n$ becomes large, it may not be possible to calculate the probabilities by hand calculation or using a calculator.

We can approximate the binomial distribution with a normal distribution or a Poisson distribution.

Making a color scheme for graphs in Stata

enayet — Thu, 23 Feb 2012 14:49:46 +0000

The article outlines the steps required to make a stata graph template or stata scheme. Stata schemes control how a particular graph will look like in terms of color, line styles, and all other aesthetic aspects.

Data Analysis with Stata

enayet — Wed, 22 Jun 2011 01:30:07 +0000

Stata is a popular statistical package for data analysis. This is one of the popular statistical packages that is being used by researchers and practitioners alike. Most notable users are from Epidemiology, Econometrics, Sociology.

Export a Table Created by R to a TeX File

tanvir — Mon, 18 Apr 2011 00:53:45 +0000

Producing tables in LaTeX might be a difficult task as we can not just copy and paste a table in the editor; we have to write all the numbers and other codes. But with the help of xtable package of R it is possible to produce all the necessary codes for producing table in LaTeX and also possible to export the codes in a tex file. Suppose we have produced summary statistics for Air Pollution Data and now want to export it to a tex file as a tabular format. Here are the codes-

library(xtable)
data<-read.table("data_air.txt", header=T)
data<-data[,1:4]
s<-summary(data)