GARP is an acronym for Genetic Algorithm for Rule Set Production. GARP is an algorithm primarily designed for predicting the potential distribution of biological entities from raster based environmental and biological data. This post describes examples of the interpretation of different sets of rules developed by GARP. Abundance of Greater Glider The Greater Glider (Petauroides volans) is a species of gliding possum found extensively in old-growth forest regions of South Eastern Australia. It Read more [...] none

The problem with many models, from climate systems to multiple species and ecosystems processes, to consumer purchasing behaviour is that we often have very little understanding of the actual relationships between the variables in the system. From our limited vantage point as observers of and not experimenters on systems we only see many weakly correlated variables, often drawn from incomplete samples and widely ranging sources. We need an automated method of developing structure from the given Read more [...] one

Niche marketing is the process of finding and serving small but potentially profitable market segments. These small market segments can be visualized as part of a "long tail", a term elaborated by Chris Anderson in his longtail blog. Niche markets are important for small businesses, as they can find it profitable to serve markets too small for mainstream businesses. Anderson argues that products with low sales volume can collectively exceed the relatively few current bestsellers. An example is Read more [...] 2 com

Think faster than "How to write a book in 28 days". With the freely available R language you can create a book in less than 28 seconds. Unfortunately, you still have to write the text and do the programming. What you can do is integrate the R code and text into the same files, then generate the figures and latex text together. This adds a lot of flexibility and organization for highly technical productions, and avoids the hassle of cross referencing. In my book, "Niche Modeling" which finally Read more [...] 11 com

The process behind the Mann "hockey stick" paper, featured by Al Gore in his movie "An Inconvienient Truth" has been damned by the US National Academy of Sciences Report. (the Wegman Report.) But how much difference should this make to belief in global warming? The Wegman report addresses one of the questions asked by Barton's office: How central is the work of Drs. Mann, Bradley, and Hughes to the consensus on the temperature record? Ans: MBH98/99 has been politicized by the IPCC and other public Read more [...] one

I'll make it clear from the outset that the falsification of data by Hwang Woo Suk and flawed results of Mann Bradley and Hughes are completely different situations. There are some similarities though. One, seemed to open a door to therapeutic cloning that could benefit millions of people with debilitating illnesses such as Alzheimer's and Parkinson's disease. The others provided a breakthough view of millennial climate history that seemed to prove humans were altering climate in an unprecedented Read more [...] none

According to the Wall Street Journal editorial, a semiretired Toronto minerals consultant and an economist, with about $5,000 of his own money and time, took on an apparently simple task -- trying to double-check the influential graphic known as the "hockey stick" -- and eventually confronted an influential scientific community before a Congressional Committee, and won. What was the sequence of events? 1990 -- MWP -- Based on numerous anecdotal studies, the Intergovernmental Panel on Climate Change Read more [...] 3 com

The WHO Epidemic and Pandemic Alert and Response reports no change in the spatial distribution of human cases of H5N1 avian influenza, although cases occurring in Indonesia is consistent with linear projections. Below are most recent cases from affected countries. Azerbaijan -- 11 April 2006 -- The case is a 17-year-old girl who developed symptoms on 11 March. She was seriously ill with bilateral pneumonia but has since fully recovered and been discharged from hospital. Cambodia -- 6 April 2006 Read more [...] none

The coefficient of determination, or r2, is the ratio of explained variation to total variation of two variables X and Y. The coefficient ranges from −1 to 1, where a value of 1 is an exact, positive linear relationship, with all data points lying on the same line. A value of 0 shows no linear relationship between the variables. If r2 is high, most people assume X and Y are related. Possibly, if the errors are "normal" or independent and identically distributed. But r2 may also be high Read more [...] 6 com

From forecasting the onset of the Monsoon in India, to mapping the drought in the USA, and worsening drought in Australia, insight from statistics into rainfall patterns affects everyone. The following documents contain technical information on regression models and rainfall, organized from the simplest linear regression to the more technical local spatial and temporal fitting techniques. Statistics 301 Handout #30: Simple Linear Regression contains R code with simple regression exercises. Partial Read more [...] none

Just after the release of the National Academy of Sciences report 'Surface Temperature Reconstructions for the Last 2,000 Years' I compared the ‘hockey stick graph’ — a reconstruction of Millennial global temperatures based on tree-ring and other proxies by Mann and colleagues -- to a broadway production in The Intelligent Design of MBH98. Statistics packages like R are fun for 'doing it yourself' and getting involved in the debates. However, for critical policy oriented work Read more [...] 2 com

The autocorrelation function is one of the Niche model basics in the R language. The ACF is the real deal when it comes to diagnosing the internal character of series data, as was done for scale invariance in Scale Invariance for Dummies. Questions of internal character of series are very topical, such as "How Red are My Proxies" where it was claimed that global temperatures are barely AR(1) contrary to views of a colleague discussed in "A Mistake with Repercussions". The ACF function in R contains Read more [...] none

To develop global distribution models of species you need global data. A major component of the datamining methodology in WhyWhere is access to a large number of global datasets. At last count over 1000 layers were available for download, testing for correlates and building models. These are organized as lists. The following are the lists with the number of global variables in each list in brackets. Clicking on the link lists the files in the list, with links to the meta data, a thumbnail image Read more [...] none

Biodiversity modeling is about multiple species and their relationships, in contrast to individual species and their environment. This leads to slightly different approaches and problems. My selection of the documents of historic influence, the programs in the field, and some of the more important recent papers follow. Reports An Interim Biogeographic Regionalisation for Australia: A Framework for Setting Priorities in the National Reserves System Cooperative Program. - R Thackway and I D Read more [...] none

If you have an interest in Statistics packages, for finance, investment, or science, you soon find out how expensive they are. I thought I would do a short survey of the standard statistical packages, and see how the free ones compare. MiniTab -- "The World Trusts Minitab for Quality". A 30 day free demo is available. The market for Minitab is corporate quality improvement. It appears to have a nice graphics and user interface and a simple macro language. The cost is $1195. The product seems Read more [...] 4 com

Niche modeling is about using probability distributions to predict. From the obscure journal article department comes a strategy for winning at Lotto using niche modeling. Schemes have often been proposed to predict the best numbers for lotteries. One of the most common uses the fact that some numbers are bet more than others, thus betting the unpopular numbers increases returns. A paper entitled Estimating the Frequency Distribution of the Numbers Bet on the California Lottery by Mark Finkelstein, Read more [...] none

This book is a compilation of arguments against Intelligent Design (ID), from sixteen of the world's leading evolutionary biologists. It includes the full text of the Harrisberg PA, Dec. 20 judgement where a federal judge ruled against teaching ID in schools. The book will reinforce the arguments of the judge and perhaps stop ID from gaining a foothold in schools in other states. An entire school board advocating teaching a supernatural explanation for natural events reminds one of why its necessary Read more [...] one

Here is a summary of the chapters in my upcoming book Niche Modeling to be published by CRC Press. Many of the topics have been introduced as posts on the blog. My deepest thanks to everyone who has commented and so helped in the refinement of ideas, and particularly in providing motivation and focus. Writing a book is a huge task, much of it a slog, and its not over yet. But I hope to get it to the publishers so it will be available at the end of this year. Here is the dustjacket blurb: Through Read more [...] 4 com

Statistical Predictive Models in Ecology: Comparison of Performances and Assessment of Applicability Authors: Can Ozan Tan, Uygar Ozesmi, Meryem Beklioglu, Esra Per, Bahtiyar Kurt Comments: Submitted to Ecological Informatics This interesting study on the open archive site arXiv (now in Ecological Informatics 1:195-211) compares some predictive models for species distribution not examined in the study of EG+06, reviewed in Novel methods continue to improve prediction of species’ distributions. Read more [...] none