Probabilistic Hierarchical Forecasting with Deep Poisson Mixtures

Hierarchical forecasting problems arise when time series have a natural group structure, and predictions at multiple levels of aggregation and disaggregation across the groups are needed. In such problems, it is often desired to satisfy the aggregation constraints in a given hierarchy, referred to as hierarchical coherence in the literature. Maintaining hierarchical coherence while producing accurate forecasts can be a challenging problem, especially in the case of probabilistic forecasting. We present a novel method capable of accurate and coherent probabilistic forecasts for hierarchical time series. We call it Deep Poisson Mixture Network (DPMN). It relies on the combination of neural networks and a statistical model for the joint distribution of the hierarchical multivariate time series structure. By construction, the model guarantees hierarchical coherence and provides simple rules for aggregation and disaggregation of the predictive distributions. We perform an extensive empirical evaluation comparing the DPMN to other state-of-the-art methods which produce hierarchically coherent probabilistic forecasts on multiple public datasets. Compared to existing coherent probabilistic models, we obtained a relative improvement in the overall Continuous Ranked Probability Score (CRPS) of 11.8% on Australian domestic tourism data, and 8.1% on the Favorita grocery sales dataset.Comment: Probabilistic Hierarchical Forecasting, Neural Networks, Poisson Mixtures, Preprint submitted to IJ

On the order of BEC transition in weakly interacting gases predicted by mean-field theory

Predictions from Hartree-Fock (HF), Popov (P), Yukalov-Yukalova (YY) and $t$-matrix approximations regarding the thermodynamics from the normal to the BEC phase in weakly interacting Bose gases are considered. By analyzing the dependence of the chemical potential $\mu$ on temperature $T$ and particle density $\rho$ we show that none of them predicts a second-order phase transition as required by symmetry-breaking general considerations. In this work we find that the isothermal compressibility $\kappa_{T}$ predicted by these theories does not diverge at criticality as expected in a true second-order phase transition. Moreover the isotherms $\mu=\mu(\rho,T)$ typically exhibit a non-singled valued behavior in the vicinity of the BEC transition, a feature forbidden by general thermodynamic principles. This behavior can be avoided if a first order phase transition is appealed. The facts described above show that although these mean field approximations give correct results near zero temperature they are endowed with thermodynamic anomalies in the vicinity of the BEC transition. We address the implications of these results in the interpretation of current experiments with ultracold trapped alkali gases.Comment: 16 pages, 5 figure

Observational constraints on an interacting dark energy model

We use observations of cosmic microwave background anisotropies, supernova luminosities and the baryon acoustic oscillation signal in the galaxy distribution to constrain the cosmological parameters in a simple interacting dark energy model with a time-varying equation of state. Using a Monte Carlo Markov Chain technique we determine the posterior likelihoods. Constraints from the individual data sets are weak, but the combination of the three data sets confines the interaction constant $\Gamma$ to be less than 23% of the expansion rate of the Universe $H_0$; at 95% CL $-0.23 < \Gamma/H_0 < +0.15$. The CMB acoustic peaks can be well fitted even if the interaction rate is much larger, but this requires a larger or smaller (depending on the sign of interaction) matter density today than in the non-interacting model. Due to this degeneracy between the matter density and the interaction rate, the only observable effect on the CMB is a larger or smaller integrated Sachs-Wolfe (ISW) effect. While SN or BAO data alone do not set any direct constraints on the interaction, they exclude the models with very large matter density, and hence indirectly constrain the interaction rate when jointly analysed with the CMB data. To enable the analysis described in this paper, we present in a companion paper [arXiv:0907.4981] a new systematic analysis of the early radiation era solution to find the adiabatic initial conditions for the Boltzmann integration.Comment: 16 pages, 10 figures. V2: Improved typography (2-column format); References and a motivation of CPL parametrization added; Accepted by MNRA

Deforestación y reforestación en la Sierra de Guadalupe, Estado de México, como un sistema social en red.

Deforestation is a complex and multifactorial problem. In Mexico, this phenomenon is exacerbated by urbanization in metropolitan areas. The Sierra de Guadalupe is situated in the Valley of Mexico and is a Protected Natural Area (PNA) that has been continually devastated by encroaching human settlement. In the area of mountain range located in the State of Mexico, attempts have been made to counteract deforestation with reforestation in degraded areas. However, these activities have been modified by the social, economic and political realities of this area. Our aim was to analyze the reforestation process in the Sierra de Guadalupe in the State of Mexico, during the period 2009-2020, by analyzing the social network and the structural phenomenon generated between social actors, reforested places and species used. Results indicated that 416.9 hectares have been reforested, affecting 75 localities, with participation of around 300 social actors, using 50 species, of which only 15 are native to the Sierra de Guadalupe ecosystem. Unequal distribution of resources used for reforestation was apparent, when comparing the municipalities analyzed (Coacalco, Ecatepec, Tlalnepantla and Tultitlán), despite being part of the same ecological corridor.La deforestación es una problemática compleja y multifactorial. En México, este fenómeno se agudiza por la urbanización en las zonas metropolitanas. En la Cuenca de México, se encuentra la Sierra de Guadalupe, un Área Natural Protegida que ha sido devastada continuamente por los asentamientos humanos. En la porción de la sierra ubicada en el Estado de México, se ha tratado de contrarrestar la deforestación con reforestaciones en zonas degradadas. Sin embargo, estas actividades se han visto modificadas por las realidades sociales, econó­micas y políticas de dicha zona. El objetivo, fue analizar el proceso de reforestación en la Sierra de Guadalupe en el Estado de México, en el periodo 2009-2020, utilizando el análisis de redes sociales y la representación estructural generada entre actores sociales, lugares reforestados y especies empleadas. Los resultados mostraron que se han reforestado 416.9 hectáreas, incidiendo en 75 localidades, donde han participado alrededor de 300 actores sociales, utilizándose 50 especies, de las cuales, únicamente 15 son nativas del ecosistema de la Sierra de Guadalupe. Se observó una distribución desigual de los recursos utilizados en las reforestaciones, entre los municipios analizados (Coacalco, Ecatepec, Tlalnepantla y Tultitlán), a pesar de ser parte del mismo corredor ecológico

The Impact of Elicitation on Potato (Solanum tuberosum L.) Production, Enzymatic and Antioxidant Activity in Nuevo León, Mexico

Many compounds available in the market act as elicitors and can be incorporated into agronomic management. But the focus is on elicitors frequently used for the induction of different responses related to the systemic resistance of plants to increase the production of bioactive metabolites, biomass accumulation, and yield. For that case, this work aimed to evaluate the effects of three elicitors on potato crops under field conditions. The potato cultivar "Fianna" was used, and a completely randomized design with four treatments and four repetitions. The effect of three elicitors at a dose of 2.5 g. L-1 for Activane®, 2.5 ml. L-1 for Micobiol® and 2.5 g. L-1 for Stemicol® was evaluated on growth, yield, enzymatic and antioxidant activity. Generally, the elicitors had a positive effect on the enzymes and antioxidant capacity of the potato plant. It was concluded that the application of elicitors Stemicol® (T4) had the most significant result on the number of tubers and weight per plant at harvest while allowing a more substantial number of tubers to be obtained. In comparison, Activane® (T2) influenced the growth variables of stem length and number of leaves per plant

Unified model of baryonic matter and dark components

We investigate an interacting two-fluid cosmological model and introduce a scalar field representation by means of a linear combination of the individual energy densities. Applying the integrability condition to the scalar field equation we show that this "exotic quintessence" is driven by an exponential potential and the two-fluid mixture can be considered as a model of three components. These components are associated with baryonic matter, dark matter and dark energy respectively. We use the Simon, Verde & Jimenez (2005) determination of the redshift dependence of the Hubble parameter to constrain the current density parameters of this model. With the best fit density parameters we obtain the transition redshift between non accelerated and accelerated regimes z_{acc}=0.66 and the time elapsed since the initial singularity t_0= 19.8 Gyr. We study the perturbation evolution of this model and find that the energy density perturbation decreases with the cosmological time.Comment: 8 pages, 6 figures A new section adde

Effects of Elicitation on Invitro Regeneration of two Tomato (Solanum lycopersicum L.) Cultivars in Tissue Culture

Exploring alternative avenues, in vitro culture emerges as a promising option for potential bioactive compound sources. However, compared to intact plants, only a few cultures demonstrate efficient synthesis of secondary metabolites. Elicitors have gained prominence as stress agents for enhancing in vitro micropropagation in specific tissues, organs, and cells. Recent advancements in plant tissue culture involve elicitors, opening new possibilities for in vitro production of crucial food crops. This research aimed to investigate the impact of three elicitors (Activane®, Micobiol®, and Stemicol®) on germination and in vitro multiplication of two tomato cultivars explants, employing both direct and indirect in vitro organogenesis. Among the texted elicitors, Micobiol® emerged as a successful elicitor, promoting optimal seed germination, survival, and 100% growth compared to the 80% in the control group. Further, Activane® exhibited a favourable induction response and achieved 96%, 95%, and 100% in weight and diameter of callus, yet various elicitor concentrations did not exert significant influence across treatments. In conclusion, an effective disinfection and in vitro implantation of tomato seeds ensured successful germination, promoting seedling survival and growth. Various elicitors positively impacted in vitro organogenesis, particularly in root induction, with higher survival percentages in acclimatized plants. The study guides future research on elicitor treatments for large-scale tomato in vitro propagation, emphasizing the need to identify optimal elicitor concentrations

Potencial de conversión de explotaciones ganaderas convencionales a sistemas de producción orgánicos en el estado de Tabasco

The main objective of the present study was to assess the conversion potential of conventional cattle farms to organic production systems. Research began by evaluating data in the Tabasco Livestock Farms Inventory 2000 (1,718 records), which provided basic and general information about the state of affairs of livestock in the aforesaid state, and permitted having an in-depth look at the production systems from an organic viewpoint. Subsequently, an Index of Compliance with Organic Standards (ICOS) was generated, which identifies the conversion potential of ranches from conventional to organic production systems. Producers with an ICOS close to 1 would only need to introduce a few changes in their management practices in order to carry out this conversion. In Tabasco, large-scale cattle farms (152 ha and 175 head, on average) have more possibilities to switch to organic production, than small-scale units (20 ha and 35 head, on average). Some 7.1 % of producers have the necessary potential to carry out this adaptation in a period of time no greater than two years, moreover, it can also be concluded that 76 % of producers, upon implementing some modifications in their production units, could achieve the same in a period no greater than four years, the rest of the cattle farms would need a period greater than four years to undertake major modifications in their management practices in order to make the changeover to an organic production system.El objetivo fundamental fue analizar el potencial de conversión de explotaciones ganaderas convencionales a sistemas de producción orgánicos, a partir de la base de datos del Inventario Ganadero Tabasco 2000 (1,718 registros), el cual proporciona datos básicos y generales sobre la situación de la ganaderí­a bovina en dicho Estado, y permite tener un acercamiento a los sistemas de producción desde la perspectiva orgánica. Se generó el índice de Cumplimiento de la Normatividad Orgánica (ICNO), que identifica el potencial de conversión de ranchos con sistemas de producción convencionales a ranchos bajo la normatividad orgánica. Las unidades de producción con un valor del ICNO cercano a 1 necesitan realizar pocas modificaciones a su sistema de manejo para su conversión. Los grandes ganaderos tabasqueÅ„,,os (152 ha y 175 cabezas, en promedio) presentan mayores posibilidades de convertir sus unidades de producción a un sistema orgánico, en comparación con los pequeÅ„,,os (20 ha y 35 cabezas, en promedio). Se estima que el 7.1 % de los productores tienen el potencial para llevar a cabo la conversión en un lapso no mayor de dos aÅ„,,os, y es posible que el 76 % de los productores, instrumentando algunas modificaciones en sus unidades de producción, pueden lograrla en un periodo no mayor de cuatro aÅ„,,os, el resto de los ganaderos necesitarí­an un plazo superior a cuatro aÅ„,,os y realizar modificaciones fuertes en las prácticas de manejo, para integrarse a un sistema de producción orgánico

Observational constraints on the braneworld model with brane-bulk energy exchange

We investigate the viability of the braneworld model with energy exchange between the brane and bulk, by using the most recent observational data related to the background evolution. We show that this energy exchange behaves like a source of dark energy and can alter the profile of the cosmic expansion. The new Supernova Type Ia (SNIa) Gold sample, Supernova Legacy Survey (SNLS) data, the position of the acoustic peak at the last scattering surface from the Wilkinson Microwave Anisotropy Probe (WMAP) observations and the baryon acoustic oscillation peak found in the Sloan Digital Sky Survey (SDSS) are used to constrain the free parameters of this model. To infer its consistency with the age of the Universe, we compare the age of old cosmological objects with what computed using the best fit values for the model parameters. At 68% level of confidence, the combination of Gold sample SNIa, Cosmic Microwave Background (CMB) shift parameter and SDSS databases provide $\Omega_m=0.29_{-0.02}^{+0.03}$, $\Omega_{A}=-0.71_{-0.03}^{+0.03}$ and $\mu=-0.40_{-0.26}^{+0.28}$, hence a spatially flat Universe with $\Omega_K=0.00_{-0.04}^{+0.04}$. The same combination with SNLS supernova observation give $\Omega_m=0.27_{-0.02}^{+0.02}$, $\Omega_{A}=-0.74_{-0.02}^{+0.04}$ and $\mu=0.00_{-0.30}^{+0.30}$ consequently provides a spatially flat Universe $\Omega_K=-0.01_{-0.03}^{+0.04}$. These results obviously seem to be compatible with the most recent WMAP results indicating a flat Universe.Comment: 17 pages and 18 figures, V2: Added comments, references, explained some topics related to the matter power spectrum as a robust constraint, accepted for publication in Mon. Not. R. Astron. So

Ab-initio Quantum Enhanced Optical Phase Estimation Using Real-time Feedback Control

Optical phase estimation is a vital measurement primitive that is used to perform accurate measurements of various physical quantities like length, velocity and displacements. The precision of such measurements can be largely enhanced by the use of entangled or squeezed states of light as demonstrated in a variety of different optical systems. Most of these accounts however deal with the measurement of a very small shift of an already known phase, which is in stark contrast to ab-initio phase estimation where the initial phase is unknown. Here we report on the realization of a quantum enhanced and fully deterministic phase estimation protocol based on real-time feedback control. Using robust squeezed states of light combined with a real-time Bayesian estimation feedback algorithm, we demonstrate deterministic phase estimation with a precision beyond the quantum shot noise limit. The demonstrated protocol opens up new opportunities for quantum microscopy, quantum metrology and quantum information processing.Comment: 5 figure