Generalized linear latent variable models (GLLVM) are popular tools for modeling multivariate, correlated responses. Such data are often encountered, for instance, in ecological studies, where presence-absences, counts, or biomass of interacting species are collected from a set of sites. Until very recently, the main challenge in fitting GLLVMs has been the lack of computationally efficient estimation methods. For likelihood based estimation, several closed form approximations for the marginal likelihood of GLLVMs have been proposed, but their efficient implementations have been lacking in the literature. To fill this gap, we show in this paper how to obtain computationally convenient estimation algorithms based on a combination of either the Laplace approximation method or variational approximation method, and automatic optimization techniques implemented in software. An extensive set of simulation studies is used to assess the performances of different methods, from which it is shown that the variational approximation method used in conjunction with automatic optimization offers a powerful tool for estimation.

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Sudarmono. 2018. Decreased populations of Scutellaria discolor and Plectranthus galeatus (Lamiaceae) on Mount Gede, West Java, Indonesian and its surrounding. Biodiversitas 19: 1866-1870. Scutellaria discolor Colebr. and Plectranthus galeatus Vahl. are herbs belonging to mint family (Lamiaceae) which have the potential to be used for medicinal purposes. However, their population is gradually declining. The population of the two species are now only found in the mountains or highlands or the edges of the forests that are still protected, i.e. Mount Gede and Telaga Warna protected forest. This research aimed to know the condition of parent and seedling population of Scutellaria discolor Colebr and Plectranthus galeatus Vahl. on Mount Gede and Telaga Warna vicinities, West Java Province, Indonesia. The research method used was parallel transect lines. Association of the existing plants in the vicinity of the area were also observed. In Mount Gede at altitudes about 1200 m above sea level there are 203 seedlings and 167 parents of S. discolor species, while there are 69 seedlings and 11 parents of P. galeatus. This is higher than the populations of 1100 m altitude, i.e. there are 76 seedlings and 45 parents of S. discolor and 12 seedlings and 9 parents of P galeatus. In Telaga Warna, S. discolor exist only at altitudes about 1500 m asl., i.e.. 47 seedlings and 52 parents. While for P. galeatus, there are 37 seedlings and 31 parents at altitudes about 1500 m. At altitude below 1400 m, there are 18 seedlings and 8 parents, this is very rare. Populations of S. discolor and P. galeatus in Mount Gede at an altitude between 1100-1300 m asl is a balance between the seedlings and its parent population which is the same for seedling populations of S. discolor in Telaga Warna at an altitude of 1400-1500 m asl, but for P. galeatus seedling number decreases from an altitude of 1400 to 1500 m asl.

Banteng, Bos javanicus, as wild cattle is a vital and importance source of germplasm in Indonesia. Various human activities currently threaten their conservation status. Nonetheless, no long-term monitoring programmes are in place for this species. Using distribution point and statistical analysis based on 46,116 camera trap days from December 2015 to January 2017, we aimed to provide habitat preferences, activity patterns and ecological data for banteng population in Ujung Kulon National Park (UKNP). It is the largest population of banteng in Indonesia and is living in a limited habitat area. According to the best occupancy model, the most suitable areas for this species were the secondary forest located at the center portion of UKNP. The presence of the invasive cluster sugar palm, Arenga obtusifolia, in dry season provides additional alternative food for banteng when its main food is scarcer in the forest. Banteng was cathemeral all year round, with the proportion of cathemeral records and the recording rate did not change with the protection of the level area, moon phase or season. To reduce the probability of encountering predators, banteng avoided the space use of dholes. Selection and avoidance of habitats was stronger than avoidance of the predator activity areas. Habitat competition from domestic cattle which grazed illegally in the national park appears to be a problem to the species since zoonosis appears from domestic cattle to banteng. Therefore, effective law enforcement and an adequate conservation strategy are required to eliminate the impacts of both direct and indirect threats.

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