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AbstractThe Additive Voronoi Tessellations (AddiVortes) model is a multivariate regression model that uses Voronoi tessellations to partition the covariate space in an additive ensemble model. Unlike other partition methods, such as decision trees, this has the benefit of allowing the boundaries of the partitions to be non-orthogonal and non-parallel to the covariate axes. The AddiVortes model uses a similar sum-of-tessellations approach and a Bayesian backfitting MCMC algorithm to the BART model. We utilize regularization priors to limit the strength of individual tessellations and accepts new models based on a likelihood. The performance of the AddiVortes model is illustrated through testing on several data sets and comparing the performance to other models along with a simulation study to verify some of the properties of the model. In many cases, the AddiVortes model outperforms random forests, BART and other leading black-box regression models when compared using a range of metrics. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

Many methods for modeling functions over high-dimensional spaces assume global smoothness properties; such assumptions are often violated in practice. We introduce a method for modeling functions that display heterogeneity or contain discontinuities. The heterogeneity is dealt with by using a combination of Voronoi tessellation, to partition the input space, and separate Gaussian processes to model the function over different regions of the partitioned space. The proposed method is highly flexible since it allows the Voronoi cells to combine to form regions, which enables nonconvex and disconnected regions to be considered. In such problems, identifying the borders between regions is often of great importance and we propose an adaptive sampling method to gain extra information along such borders. The method is illustrated by simulated examples and an application to real data, in which we see improvements in prediction error over the commonly used stationary Gaussian process and other nonstationary variations. In our application, a computationally expensive computer model that simulates the formation of clouds is investigated, the proposed method more accurately predicts the underlying process at unobserved locations than existing emulation methods. for this article are available online. [ABSTRACT FROM AUTHOR]

John Gosling interviews Bill Hayes, author of the memoir Insomniac City: New York, Oliver, and Me. This interview explores Bill's experience of his creative process in writing this moving memoir. His six-year relationship (and subsequent loss to death) with renowned neurologist and author Oliver Sacks served as a source of inspiration for him. Bill reveals how his remarkable creative process, which was different from anything he had previously experienced, unfolded over a six-week period while on a scholarship in Rome. He describes how the many losses and deaths he has experienced have informed his creativity and capacity to be more present in his life. He is also a photographer, and he interspersed several of his New York photographs in the book while describing quite movingly his love affair with New York and the people he encounters on its streets. He ascribes his interest in photography to a template in his unconscious from his childhood experiences of being surrounded by books and magazines of photojournalism. Our creativity—what inspires us, where it originates, and how it manifests in us as humans—remains a mystery. This interview offers a window through which we can glimpse the unique creative process of one person who is an author and a photographer. [ABSTRACT FROM AUTHOR]

This article briefly outlines and explores the concept of gender fluidity expressed by genderqueer persons that offers an alternative to our customary binary gender identities. This development allows for the possibility of the expression of nonconforming gender neutrality as the stereotypical heteronormative gender expectations are slowly being eroded. A few examples of contemporary gender fluid persons are included. Gender fluidity is also conceptualized from an analytical psychology perspective with reference to androgynous archetypal energies referred to by Jung as “The Original Man that is usually hermaphroditic.” [ABSTRACT FROM AUTHOR]

The article discusses the myth of Taliesin, an early Brythonic poet of Sub-Roman Britain. According to the author, the myth depicts the psychological growth and the pathway leading to wisdom. Particular focus is given to the archetypical feminine energies that possess the ability to fabricate new life.

Vegetable oils and fats make up a significant part of the energy intake in typical European diets. However, their use as ingredients in a diverse range of different foods means that their consumption is often hidden, especially when oils and fats are used for cooking. As a result, there are no reliable estimates of the consumption of different vegetable oils and fats in the diet of European consumers for use in, for example, nutritional assessments or chemical risk assessments. We have developed an innovative model to estimate the consumption of vegetable oils and fats by European Union consumers using the European Union consumption databases and elements of probabilistic modelling. A key feature of the approach is the assessment of uncertainty in the modelling assumptions that can be used to build user confidence and to guide future development. [ABSTRACT FROM AUTHOR]

Computer simulators of real-world processes are often computationally expensive and require many inputs. The problem of the computational expense can be handled using emulation technology; however, highly multidimensional input spaces may require more simulator runs to train and validate the emulator. We aim to reduce the dimensionality of the problem by screening the simulator’s inputs for nonlinear effects on the output rather than distinguishing between negligible and active effects. Our proposed method is built upon the elementary effects (EE) method for screening and uses a threshold value to separate the inputs with linear and nonlinear effects. The technique is simple to implement and acts in a sequential way to keep the number of simulator runs down to a minimum, while identifying the inputs that have nonlinear effects. The algorithm is applied on a set of simulated examples and a rabies disease simulator where we observe run savings ranging between 28% and 63% compared with the batch EE method. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]