English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

This work proposes an adjacent-category autoregressive model for time seriesof ordinal variables. We apply this model to dendrochronological records tostudy the effect of climate on the intensity of spruce budworm defoliationduring outbreaks in two sites in eastern Canada. The model's parameters areestimated using the maximum likelihood approach. We show that this estimator isconsistent and asymptotically Gaussian distributed. We also propose aPortemanteau test for goodness-of-fit. Our study shows that the seasonal rangesof maximum daily temperatures in the spring and summer have a significantquadratic effect on defoliation. The study reveals that for both regions, agreater range of summer daily maximum temperatures is associated with lowerlevels of defoliation up to a threshold estimated at 22.7C (CI of 0-39.7C at95%) in T\'emiscamingue and 21.8C (CI of 0-54.2C at 95%) for Matawinie. ForMatawinie, a greater range in spring daily maximum temperatures increaseddefoliation, up to a threshold of 32.5C (CI of 0-80.0C). We also present astatistical test to compare the autoregressive parameter values betweendifferent fits of the model, which allows us to detect changes in thedefoliation dynamics between the study sites in terms of their respectiveautoregression structures.

Adjacent-category models for ordinal time series and their application to climate-dependent spruce budworm defoliation dynamics