What Level of Statistical Model Should We Use in Small Area Estimation?

If unit‐level data are available, small area estimation (SAE) is usually based on models formulated at the unit level, but they are ultimately used to produce estimates at the area level and thus involve area‐level inferences. This paper investigates the circumstances under which using an area‐level model may be more effective. Linear mixed models (LMMs) fitted using different levels of data are applied in SAE to calculate synthetic estimators and empirical best linear unbiased predictors (EBLUPs). The performance of area‐level models is compared with unit‐level models when both individual and aggregate data are available. A key factor is whether there are substantial contextual effects. Ignoring these effects in unit‐level working models can cause biased estimates of regression parameters. The contextual effects can be automatically accounted for in the area‐level models. Using synthetic and EBLUP techniques, small area estimates based on different levels of LMMs are investigated in this paper by means of a simulation study.     

Out of mind,out of sight? Leading distributed workers to ensure health and safety

ABSTRACT

Current frameworks of leadership are based on face-to-face interaction. A growing number of workers work away from their main location of work; this makes it challenging for leaders to ensure the health and safety of distributed workers. In the present study, we explore the relationship between line managers’ health and safety leadership and distributed workers’ health and safety behaviours. We also explore the organisational procedures and practices that may enhance the impact of health and safety leadership. We included a broad range of distributed workers (in analyses, minimum N?=?626) from 11 organisations. We found that health-and-safety-specific leadership was positively related to distributed workers’ self-rated health, safety compliance and safety proactivity. These relationships were augmented by distributed workers’ sense of being included in the workplace. Knowledge sharing among colleagues was associated with safety compliance when health-and-safety-specific leadership was low. Our results indicate that one way of addressing the challenges of distributed working may be through line managers putting health and safety on the agenda.     

Modeling and optimizing an agro-supply chain considering different quality grades and storage systems for fresh products: a Benders decomposition solution approach

This paper proposes a mathematical model in the context of agro-supply chain management, considering specific characteristics of agro-products to assist purchase, storage, and transportation decisions. In addition, a new method for determining the required quality score of different types of products is proposed based on their loss factors and purchasing costs. The model aims to minimize total cost imposed by purchasing fresh products, opening warehouses, holding inventories, operational activities, and transportation. Two sets of examples, including small and medium-sized problems, are implemented by general algebraic modeling language (GAMS) software to evaluate the model. Then, Benders decomposition (BD) algorithm is applied to tackle the complexity of solving large-sized instances. The results of both GAMS and BD are compared in terms of objective function values and computational time to demonstrate the efficiency of the BD algorithm. Finally, the model is applied in a real case study involving an apple supply chain to obtain managerial insights.

     

How I wonder what you are: Children's songs as a source of mental and internal state information

This study investigated (1) whether children's songs could be potential sources of internal state information and (2) cross-cultural/linguistic differences in the availability of such information. We coded for expressions of mental states and other internal states in 255 English songs, likely accessed by children in the United States, and 255 Japanese songs, likely accessed by Japanese children. The majority of the songs in both samples contained at least one internal state expression, with songs containing four to five tokens and two types of internal state expressions on average. Japanese songs had more types of internal state expressions than English songs when comparing the two samples in proportion scores that controlled for the length of songs. However, differences between English and Japanese songs were negligible in the absolute frequency of tokens and types of internal state expressions, with the exception that Japanese songs were richer in ambiguous internal state expressions.