Making a case for hierarchical generalized models

Science is also about convincing others, be it your supervisors or your collaborators, that what you intend to do is relevant to get the answers sought. This “what” can be anything from designing an experiment, to collecting samples or formatting the data. This post was inspired by a recent discussion with one of my supervisor … Continue reading Making a case for hierarchical generalized models

Tendances des élections présidentielles francaises des 50 dernières années

[An english version for this article is available here] Cette année (2017) les Français seront appelés à élire leur prochain président au mois d'avril. Il y a quelque temps j'ai découvert le site open data du gouvernement français où sont publiés de nombreux jeux de données publiques et où tout un chacun est invité à … Continue reading Tendances des élections présidentielles francaises des 50 dernières années

Patterns across 50 years of French presidential election

[Une version francaise de cette article est disponible ici] This year (2017) we will have our presidential election between April and May in France. A while ago I discovered the open data website of the French government publishing public data with free access and promoting utilization by anyone. So in this post I will explore … Continue reading Patterns across 50 years of French presidential election

Prediction in ecology -implementing a priority.

In this post I would like to comment a bit on the recent forum paper by Houlahan et al on the importance of prediction to demonstrate ecological understanding. Before going through what I took from the paper I will outline a bit where I stood on prediction and understanding before reading the article. Explanation vs … Continue reading Prediction in ecology -implementing a priority.

Spatial Dynamic in a Host-Parasitoid system

In this post I will explore the spatial dynamic that arise from a simple deterministic host-parasitoid model with migration in a homogeneous environment. If the previous sentence did not drive you away, congrats (!) you are most certainly in a terminal state towards biological nerditude. The idea of this post emerged while reading Chp. 6 … Continue reading Spatial Dynamic in a Host-Parasitoid system

Crossed and Nested hierarchical models with STAN and R

Below I will expand on previous posts on bayesian regression modelling using STAN (see previous instalments here, here, and here). Topic of the day is modelling crossed and nested design in hierarchical models using STAN in R. Crossed design appear when we have more than one grouping variable and when data are recorded for each … Continue reading Crossed and Nested hierarchical models with STAN and R

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, ethnicity, social … Continue reading Hierarchical models with RStan (Part 1)