Collinearity and stepwise VIF selection

A good article for my fellow statistician and analyst

R is my friend

Collinearity, or excessive correlation among explanatory variables, can complicate or prevent the identification of an optimal set of explanatory variables for a statistical model. For example, forward or backward selection of variables could produce inconsistent results, variance partitioning analyses may be unable to identify unique sources of variation, or parameter estimates may include substantial amounts of uncertainty. The temptation to build an ecological model using all available information (i.e., all variables) is hard to resist. Lots of time and money are exhausted gathering data and supporting information. We also hope to identify every significant variable to more accurately characterize relationships with biological relevance. Analytical limitations related to collinearity require us to think carefully about the variables we choose to model, rather than adopting a naive approach where we blindly use all information to understand complexity. The purpose of this blog is to illustrate use of some techniques to reduce collinearity…

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Do Indian need Shivaji or Patel statues when we are struggling for basic amenities – Group Discussion

Topbullets.comYesterday PM Mr. Modi laid foundation for Shivaji memorial in Mumbai which will cost around 3600 crore INR ($500m). Few years back the same person Mr. Modi then CM of Gujarat laid foundation for Patel statue which will cost 3000 crore INR ($450m). Now a genuine question arises do we really need such monuments when our roads are broken, no proper infrastructure like hospitals and schools in most of the towns and villages. So today I have chosen this topic for my cast study. My points may be biased so you are most welcome to comment your thoughts or criticize me in the comment box. Continue reading

Understanding the concept of Advertisement AdStock and Importance of it in Marketing Mix Modeling

Topbullets.comAs I wrote in my previous blog that advertisement is basically nothing but a paid version of promoting your brand or product or services. Please read it here if you want to know more about advertisement and different kinds of advertisements. So companies spend millions of dollars on ads not just to make awareness of their products but also to stay in customers’ mind (retention). What is retention? Let’s discuss it today. Continue reading

How to change app drawer display in Cyanogen Android phones

Topbullets.comRecently I updated my Yu-Yuphoria Cyanogen Android phone to latest version and everything looks cool except the apps display settings. Earlier I had pager views means I could scroll left-right to access my installed apps but now I had a vertical list of all apps. All apps are arranged alphabetically. If you don’t like this view let’s change it to your original app drawer format. Continue reading

Never Let Me Go – Story by Sachin Garg and review by TopBullets.com

Topbullets.comAs far as I remember I bought this book 1.5 years back while I was in college and the moment I read his ‘Acknowledgement’, I could not dare to read it further. Actually at that time I watched a Hollywood original, Oh Yah Original movie, “Never Let me Go!” and thought of reading such kind of love story. So ended up buying this book. But the moment I read Sachin thanking Nikita and Durjoy I could not dare to turn the next page. I read one book from Durjoy – ‘Of course I love you till I find someone better’ and I didn’t like the book. All those hypocrite and exaggerated love stories where writer always shows himself a hero and a hyped love story. So I left the book in my book shelf and didn’t take it out till last night.
The article is spoiler for those who haven’t read the book. Please be warned and go ahead. Continue reading