Eco-Stats Lab, March 2014 - Measurement Error modeling using SIMEX

Measurement Error modeling using SIMEX

Date: 28th March 2-3pm
Venue: Computer Lab Room 640

Slides:

Measurement Error Modeling

• Measurement error or error-in-variables arises whenever we have imprecise measurements on our predictor variables (or covariates).
• If X is the true covariate and U is the measurement error, then what we observe is
  W = X + U:
• In a simple regression, we usually assume that our covariates are measured precisely or they represent the true covariate values quite well. But what happens to our estimates if our covariates have measurement error?

Eco-Stats Lab, Feb 2014 - SMATR

The SMATR package (Standardised Major Axis estimation and Testing Routines) is designed for when you are fitting lines and:
- you are primarily interested in the slope (rather than significance or strength of association)
- the problem is symmetric, i.e. you could happily swap which variable is on which axis without changing the meaning of what you are doing.  Or put another way, rather than predicting Y from X (regression), you have a pair of Y variables (Y1 and Y2) and you want to see how they are related to each other.

This situation commonly arises in allometry (the study of how one size variable scales against another), this is the main place these methods are useful in ecology.

MAXENT equivalence paper rated "Exceptional" on Faculty of 1000

The first paper from Ian Renner's PhD thesis, "Equivalence of MAXENT and Poisson point process models for species distribution modeling in ecology", has been rated by the Faculty of 1000.  F1000 is a post-publication peer review website that highlights noteworthy articles from the scientific literature, especially biology and medicine articles.  Renner & Warton (2013) received the top rating (three stars, "Exceptional"), which we are pretty chuffed about.  For details, see the review at http://f1000.com/prime/718270492

Eco-Stats Paper of the Year, 2013

We just had our second annual paper of the year competition, highlighting papers that made an impression to UNSW Eco-Stats researchers over the previous year.  Papers were supposed to be in print in 2013, but this was interpreted generously. And the nominees are...

Ecostats Workshop - Mixture Models

To all those coming to the UNSW Ecostats workshop on Mixture models,

Date: 31st January 2-3pm
Venue: Computer Lab Room 640...somewhere in Sydney =D
Topic: A very very short introduction to mixture models with a very very short taste of how to implement them in R
MC: Francis Hui (PhD student; UNSW School of Maths and Stats)

Please note that this blog is NOT to be used for indicating that you want to attend. That should have been done via the email sent out by Richard Kingsford earlier.

Unfortunately, blogger does not allow one to attach thing that aren't videos or images, so I've instead provided links to the material I shall be using.

Slides: https://www.dropbox.com/s/0ibha7nk2u8k22u/minilecturev1.pdf?dl=0
R script: https://www.dropbox.com/s/kg3bcyt65ec6nhl/scripts_cutdown.R?dl=0



Thank you.

Yours non-significantly,
FH

And the Academy Award for statistical ecology goes to....

While David's acting skills may not match the likes of Leonardo DiCaprio and Christian Bale, he has already won a academy award...that is, an Australian Academy of Science prize!

David has been awarded the prestigious Christopher Heyde Medal for distinguished research in mathematical sciences by a researcher under the age of 40. The award includes a cash-prize (a random variable taking a uniform distribution between one and one million dollars), which of course he will generously share amongst the members of the eco-stats group at UNSW =D

He will officially receive his award at Academy’s annual meeting in Canberra in May.

Congratulations David!

Congratulations to David-'Postdoc Supervisor of the Year’ within the Science Faculty

Congratulations to David who was recognized as the ‘Supervisor of the Year’ within the Science Faculty as nominated by the Science Postdocs tonight. A fantastic effort!