Publications by grumble10
Exploration of Functional Diversity indices using Shiny
Biological diversity (or biodiversity) is a complex concept with many different aspects in it, like species richness, evenness or functional redundancy. My field of research focus on understanding the effect of changing plant diversity on higher trophic levels communities but also ecosystem function. Even if the founding papers of this area of re...
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Confidence Intervals for prediction in GLMMs
With LM and GLM the predict function can return the standard error for the predicted values on either the observed data or on new data. This is then used to draw confidence or prediction intervals around the fitted regression lines. The confidence intervals (CI) focus on the regression lines and can be interpreted as (assuming that we draw 95% CI...
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Count data: To Log or Not To Log
Count data are widely collected in ecology, for example when one count the number of birds or the number of flowers. These data follow naturally a Poisson or negative binomial distribution and are therefore sometime tricky to fit with standard LMs. A traditional approach has been to log-transform such data and then fit LMs to the transformed data...
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Two little annoying stats detail
A very brief post at the end of the field season on two little “details” that are annoying me in paper/analysis that I see being done (sometimes) around me. The first one concern mixed effect models where the models built in the contain a grouping factor (say month or season) that is fitted as both a fixed effect term and as a random effect t...
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Plotting regression curves with confidence intervals for LM, GLM and GLMM in R
Once models have been fitted and checked and re-checked comes the time to interpret them. The easiest way to do so is to plot the response variable versus the explanatory variables (I call them predictors) adding to this plot the fitted regression curve together (if you are feeling fancy) with a confidence interval around it. Now this approach is...
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Exploring Spatial Patterns and Coexistance
Today is a rainy day and I had to drop my plans for going out hiking, instead I continued reading “Self-Organization in Complex Ecosystems” from Richard Solé and Jordi Bascompte. As I will be busy in the coming weeks with spatial models at the iDiv summer school I was closely reading chapter three on spatial self-organization and decided to ...
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Exploring the diversity of Life using Rvest and the Catalog of Life
I am writing the general introduction for my thesis and wanted to have a nice illustration of the diversity of Arthropods compared to other phyla (my work focus on Arthropods so this is a nice motivation). As the literature I have had access so far use pie charts to graphically represent these diversities and knowing that pie chart are bad, I dec...
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Simulating local community dynamics under ecological drift
In 2001 the book by Stephen Hubbell on the neutral theory of biodiversity was a major shift from classical community ecology. Before this book the niche-assembly framework was dominating the study of community dynamics. Very briefly under this framework local species composition is the result of the resource available at a particular site and spe...
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Shiny and Leaflet for Visualization Awards
Next week will be the meeting of the German (and Swiss and Austrians) ecologists in Marburg and the organizing team launched a visualization contest based on spatial data of the stores present in the city. Nadja Simons and I decided to enter the contest, our idea was to link the store data to the city bus network promoting a sustainable and safe ...
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Hierarchical models with RStan (Part 1)
Real-world data sometime show complex structure that call for the use of special models. When data are organized in more than one level, hierarchical models are the most relevant tool for data analysis. One classic example is when you record student performance from different schools, you might decide to record student-level variables (age, ethni...
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