Two-stage approaches to the analysis of occupancy data I: the homogeneous case (analysis of occupancy data)

Abstract

Occupancy models are used in statistical ecology to estimate species dispersion. The two components of an occupancy model are the detection and occupancy probabilities, with the main interest being in the occupancy probabilities. We show that for the homogeneous occupancy model there is an orthogonal transformation of the parameters that gives a natural two-stage inference procedure based on a conditional likelihood. We then extend this to a partial likelihood that gives explicit estimators of the model parameters. By allowing the separate modeling of the detection and occupancy probabilities, the extension of the two-stage approach to more general models has the potential to simplify the computational routines used there.     

Under Erasure: William Kentridge,Derrida, and Post-Apartheid South Africa

This article aims to read the work of South African artist William Kentridge through the prism of Jacques Derrida’s notion of trace. Kentridge utilizes a unique style of filmic animation: charcoal pictures drawn on a single piece of paper, where the animation is achieved by erasing and re-drawing parts of the picture, and then filming the image again. I will argue that this technique, as well as Kentridge’s focus on deferral, memory, and identity, share an affinity with the philosophical, aesthetic, ethical, and political aspects of Derrida’s trace. Drawing attention to the trace—a paradox of presence, where motion is achieved precisely by the deferred nonpresence in each drawing—Kentridge acknowledges, in a similar way to Derrida, the impossibility of ontological thought and knowing. In post-apartheid South Africa, this is not only an aesthetic statement but a political one as well. By maintaining the traces, Kentridge concedes that knowing should be deferred, acknowledging that what we know about the other is limited, if not impossible, and that the apartheid regime’s attempt to master the other was violent and erroneous.     

Walking Ability is Associated with Social Communication Skills in Infants at High Risk for Autism Spectrum Disorder

Achievement of early motor milestones in infancy affords new opportunities for social interaction and communication. Research has shown that both motor and social deficits are observed in infants who later develop autism spectrum disorder (ASD). This study examined associations between motor and Social communication skills in 12‐month‐old infant siblings of children with ASD who are at heightened risk for developmental delays (N = 86) and low‐risk, typically developing infants (N = 113). Infants were classified into one of three groups based on their walking ability: walkers (walks independently), standers (stands independently), or prewalkers (does not yet stand or walk independently). Social communication and cognitive skills were assessed with two standardized assessments (Communication and Symbolic Behaviors Scales [CSBS] and Mullen Scales of Early Learning) and compared across the three walking groups. Results demonstrated that high‐risk walkers showed superior Social communication skills, but commensurate cognitive skills, compared to high‐risk prewalkers. In contrast, Social communication and cognitive skills were largely comparable for low‐risk infants, regardless of walking status. Findings suggest that for high‐risk infants, who are already vulnerable to developmental delays and ASD, independent walking may facilitate the emergence of Social communication abilities. Pivotal motor milestones may serve as useful indicators of Social communication delays and targets for intervention.     

Do cultural orientations moderate the relation between Chinese adolescents’ shyness and depressive symptoms? It depends on their academic achievement

We examined the moderating roles of individualistic and collectivistic cultural orientations and academic achievement on the relation between Chinese adolescents’ shyness and depressive symptoms. A sample of Chinese adolescents (N = 492) from an urban school participated in the study during seventh (T1) and eighth (T2) grades. Adolescents self‐reported their shyness, cultural orientations, and depressive symptoms. The school provided records of their academic achievement. Concurrently, shyness and individualism were positively whereas collectivism and academic achievement were negatively, associated with adolescents’ depressive symptoms. Longitudinally, T1 shyness (but not individualism, collectivism, or academic achievement) predicted T2 depressive symptoms after controlling for stability in depressive symptoms. Concurrent relations between shyness and depressive symptoms were moderated by adolescents’ cultural orientations. Specifically, collectivism was protective whereas individualism was harmful, for shy adolescents’ adjustment. Furthermore, collectivism and academic achievement jointly moderated the relations between shyness and depressive symptoms concurrently and longitudinally. The results suggest that cultural orientations may influence shy adolescents’ depression symptoms through individual‐level self‐evaluation, and indicate that cultural factors and academic achievement need to be considered comprehensively for understanding and improving shy Chinese adolescents’ psychological adjustment.     

Self‐conscious Shyness: Growth during Toddlerhood,Strong Role of Genetics,and No Prediction from Fearful Shyness

Fearful and self‐conscious subtypes of shyness have received little attention in the empirical literature. Study aims included the following: (1) determining whether fearful shyness predicted self‐conscious shyness, (2) describing development of self‐conscious shyness, and (3) examining genetic and environmental contributions to fearful and self‐conscious shyness. Observed self‐conscious shyness was examined at 19, 22, 25, and 28 months in same‐sex twins (MZ = 102, DZ = 111, missing zygosity = 3 pairs). Self‐conscious shyness increased across toddlerhood, but onset was earlier than predicted by theory. Fearful shyness (observed [6 and 12 months] and parents’ reports [12 and 22 months]) was not predictive of self‐conscious shyness. Independent genetic factors made strong contributions to parent‐reported (but not observed) fearful shyness (additive genetic influence = .69 and .72 at 12 and 22 months, respectively) and self‐conscious shyness (additive genetic influence = .90 for the growth model intercept). Results encourage future investigation of patterns of change and inter‐relations in shyness subtypes.     

Being involved in the country: Productive ageing in different types of rural communities

Productive ageing recognises the contribution of older people to economic, social and cultural growth and helps build a sustainable community. Being involved in community life is good for individuals and good for society. However, we know very little about the participation of and contribution by people aged 50 and over in rural communities. This research aimed to develop a better understanding of productive ageing in different types of communities in rural Victoria, Australia. An anonymous self-complete postal questionnaire was distributed to a sample of households in twenty rural communities using the Australia Post Unaddressed Select Service. Those householders 50 years of age and older were invited to complete the survey. Data collected allowed examination of social and civic engagement, familiarity with community, the value placed on social relations by people aged 50 years and over, and how community involvement was linked to community sustainability. In particular it attempts to address the question ‘Does social and civic engagement differ across declining, stable and growing rural communities?’ Despite differences among rural communities, this study showed that older people develop and maintain strong community connections and well-functioning social capital and that participation in social activities was associated with feelings of being connected with community. It also identified health issues and lack of options as the main constraints on participation. A key message for policy makers is that older people play an important role in the sustainability of rural communities. There is much to be gained from actively supporting their participation in activities that are connected to ageing well.     

Plant-mycorrhizal fungi associations along an urbanization gradient: implications for tree seedling survival

Mycorrhizal fungi symbioses can be critical determining if established seedlings survive or not. Currently, in remnant forests, plants and their fungal symbionts are exposed to varied anthropomorphic effects related to urbanization, however, little is known about their impact on this association. We investigated the relationship between mycorrhizal fungi and tree seedling survival along an urbanization gradient. We planted three species of temperate tree seedlings (Acer rubrum, Carya ovata, and Quercus rubra) in three landscapes: urban, suburban, and rural. We measured the percent of root length colonized by mycorrhizal fungi and monitored survival during their first growing season. We analyzed mycorrhizal colonization as a function of landscape type (urban-rural) and additional variables known to contribute to mycorrhizal colonization (phosphorus, nitrogen, initial plant height). We then analyzed seedling survival as a function of the degree of mycorrhizal fungi colonization associated with the landscape gradient and of additional environmental factors (light and soil moisture). Within a species we found no changes in the levels of mycorrhizal fungi colonization across the urbanization gradient. Each species, however, had markedly different levels of colonization. Survival of A. rubrum was independent of mycorrhizal colonization, while C. ovata and Q. rubra had a significant positive response to increased mycorrhizal fungi. These findings highlight the resilience of mycorrhizal communities across the rural-urban gradient typical of this region, but they also underscore the potential sensitivity of some tree species to lower levels of mycorrhizal fungi colonization.     

Toddlers Involve Their Caregiver to Help Another Person in Need

Three experiments with 18‐ to 35‐month‐old children (n = 169) studied toddler–caregiver interactions when being confronted with another person in need. In particular, we explored whether toddlers would request their caregiver to help a needy other when they are not able to help themselves. Children observed another person who needed help to accomplish a task, but were either not able to provide help as the object was out of reach (Experiment 1) or because an obstacle prevented children from interacting with the other person (Experiments 2, 2b). The experiments revealed the same developmental trend with 2.5‐year‐olds selectively involving their caregiver to help the needy other. The results are interpreted in terms of toddlers’ motivation to see others helped and with respect to their developing ability to actively involve others to regulate their emotions.     

Thank God you're here: the coming generation and their role in future‐proofing Australia from the challenges of population ageing

Like much of the industrialised world, Australia's population is ageing, the implications of which are twofold: increasing demand for publicly funded services and a decline in the supply of prime working‐age people. In grappling with the challenges of a diminishing workforce, the Australian Government is currently relying on its migration programs to provide both the much‐needed labour and skills for the resource boom and also to stimulate the economy through population growth. However, there may be another, not yet fully considered solution to the upcoming demographic problem. This paper investigates how the grandchildren of the baby boomers, termed here the Thank God You're Here generation (Gen TGYH), might impact on Australia's predicted workforce shortage. This generation of workers will enter the labour force as the last of the baby boomers reach retirement age, and will not only be bigger in size than preceding generations (Y, X and Baby Boomers), but also potentially be better educated than the retiring generation. This paper will also canvas the opportunities for both Gen TGYH and employers as well as the challenges for policymakers and governments in maximising the opportunity provided by this generation in the Australian economy.