Posts Tagged ‘ Invasive Species ’

Walmart Invasion

August 26, 2012
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Walmart Invasion

As an invasion biologist, the process of spatial spread is at the heart of what I do. When I came across this dataset of Walmart store openings since 1962 I couldn’t help but see it as an invasion front which looks a lot like a biological invasion or (albeit slow) epidemic. The video shows monthly

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Simulation: The modeller’s laboratory

August 10, 2012
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Simulation: The modeller’s laboratory

In his 2004 paper in Trends in Ecology and Evolution, Steven Peck argues: Simulation models can be used to mimic complex systems, but unlike nature, can be manipulated in ways that would be impossible, too costly or unethical to do in natural systems. Simulation can add to theory development and testing, can offer hypotheses about the

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Use of Classification Trees to Investigate Traits of Invasive Species

September 20, 2011
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Use of Classification Trees to Investigate Traits of Invasive Species

Which traits make an alien species invasive?Due to what traits an alien species becomes established in a foreign flora?This kind of questions could be analysed by the use of recursive partitioning and classification trees..(the below example also inclu...

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Comparing Two Distributions

August 29, 2011
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Comparing Two Distributions

Here I compare two distributions, flowering duration of indigenous and allochtonous plant species. The hypothesis is that alien compared to indigenous plant species exhibit longer flowering periods.Read more »

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Test Difference between Two Proportions & Plot Confidence Intervals

August 11, 2011
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Test Difference between Two Proportions & Plot Confidence Intervals

..an illustrative example for testing proportions and presenting the results.the data: number of indigenous and alien plant species with and without vegetative reproduction. Hypothesis: The proportion of species with vegetative reproduction is differen...

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