Ricard, Ingrid
Davison, Anthony Christopher
Statistical methods for insect choice experiments
141
Censored data
Generalized linear model
Markov process
Olfactometer
Overdispersion
Parasitoid wasp
Sequential choice
Choix séquentiels
Données censurées
Guêpes parasitoïdes
Modèles linéaires généralisés
Olfactomètre
Processus de Markov
Surdispersion
2008
2008
Olfactometer experiments are used to determine the effect of odours on the behaviour of organisms such as insects or nematodes, and typically result in data comprising many groups of small counts, overdispersed relative to the multinomial distribution. Overdispersion reflects a lack of independence or heterogeneity among individuals and can lead to statistics having larger variances than expected and possible losses of efficiency. In this thesis, some distributions which consist of generalisations of the multinomial distribution have been developed. These models are based on non-homogeneous Markov chain theory, take the overdispersion into account, and potentially provide a physical interpretation of the overdispersion seen in olfactometer data. Some inference aspects are considered, including comparison of the asymptotic relative efficiencies of three different sampling schemes. The fact that the empirical distributions well approximate the corresponding asymptotic distributions is checked. Observable differences in parameter estimates between data generated under different hypotheses are also studied. Finally, different models intended to shed light on various aspects of the data and/or the experiment procedure, are applied to three real olfactometer datasets.
EPFL
4020
Theses
10.5075/epfl-thesis-4020