Accurate integration of forced and damped oscillators

The new methods accurately integrate forced and damped oscillators. A family of analytical functions is introduced known as T-functions which are dependent on three parameters. The solution is expressed as a series of T-functions calculating their coefficients by means of recurrences which involve the perturbation function. In the T-functions series method the perturbation parameter is the factor in the local truncation error. Furthermore, this method is zero-stable and convergent. An application of this method is exposed to resolve a physic IVP, modeled by means of forced and damped oscillators. The good behavior and precision of the methods, is evidenced by contrasting the results with other-reputed algorithms implemented in MAPLE.

Migrantes y migraciones: de nuevo la divergencia en las fuentes estadísticas

Este trabajo plantea una serie de deficiencias presentes en la Encuesta de Migraciones (EM), publicada anualmente por el INE a partir de la EPA. Consciente de la subestimación de la movilidad procedente de esta fuente estadística, el INE ha introducido recientemente ciertos cambios metodológicos. Sin embargo, no se han obtenido mejoras significativas y la misma continúa disponible para los investigadores. Las razones que se encuentran detrás de la limitada calidad de la EM son de tipo estadístico y afectan a la precisión y al sesgo de las estimaciones. Se desatienden principios básicos de la estimación para dominios pequeños, se incumplen los supuestos del muestreo por conglomerados y se incurre en graves sesgos debidos, probablemente, a la falta de respuesta. Consideramos que la investigación del hecho migratorio a través de la técnica del muestreo estratificado de poblaciones exige un tratamiento específico en la encuesta, dado el tamaño y las características de este dominio.

Direct versus indirect channels: Differentiated loss aversion in a high‐involvement, non‐frequently purchased hedonic product

Purpose – This article aims to investigate whether intermediaries reduce loss aversion in the context of a high-involvement non-frequently purchased hedonic product (tourism packages). Design/methodology/approach – The study incorporates the reference-dependent model into a multinomial logit model with random parameters, which controls for heterogeneity and allows representation of different correlation patterns between non-independent alternatives. Findings – Differentiated loss aversion is found: consumers buying high-involvement non-frequently purchased hedonic products are less loss averse when using an intermediary than when dealing with each provider separately and booking their services independently. This result can be taken as identifying consumer-based added value provided by the intermediaries. Practical implications – Knowing the effect of an increase in their prices is crucial for tourism collective brands (e.g. “sun and sea”, “inland”, “green destinations”, “World Heritage destinations”). This is especially applicable nowadays on account of the fact that many destinations have lowered prices to attract tourists (although, in the future, they will have to put prices back up to their normal levels). The negative effect of raising prices can be absorbed more easily via indirect channels when compared to individual providers, as the influence of loss aversion is lower for the former than the latter. The key implication is that intermediaries can – and should – add value in competition with direct e-tailing. Originality/value – Research on loss aversion in retailing has been prolific, exclusively focused on low-involvement and frequently purchased products without distinguishing the direct or indirect character of the distribution channel. However, less is known about other types of products such as high-involvement non-frequently purchased hedonic products. This article focuses on the latter and analyzes different patterns of loss aversion in direct and indirect channels.