A Risk-Based Method for Modeling Traffic Fatalities

We describe a risk-based analytical framework for estimating traffic fatalities that combines the probability of a crash and the probability of fatality in the event of a crash. As an illustrative application, we use the methodology to explore the role of vehicle mix and vehicle prevalence on long-run fatality trends for a range of transportation growth scenarios that may be relevant to developing societies. We assume crash rates between different road users are proportional to their roadway use and estimate case fatality ratios (CFRs) for the different vehicle-vehicle and vehicle-pedestrian combinations. We find that in the absence of road safety interventions, the historical trend of initially rising and then falling fatalities observed in industrialized nations occurred only if motorization was through car ownership. In all other cases studied (scenarios dominated by scooter use, bus use, and mixed use), traffic fatalities rose monotonically. Fatalities per vehicle had a falling trend similar to that observed in historical data from industrialized nations. Regional adaptations of the model validated with local data can be used to evaluate the impacts of transportation planning and safety interventions, such as helmets, seat belts, and enforcement of traffic laws, on traffic fatalities.     

“A stitch in time”: group work during the covid-19 scare in the Nicobar Islands,India

ABSTRACT

When India suddenly went into its first coronavirus-induced nationwide lockdown in March 2020, several members of a historically isolated indigenous community in the eastern Indian ocean- the Nicobarese, began to panic. Their leaders came together and formed a group to boost community solidarity and helped the vulnerable indigenes to safely navigate through the crisis. In these uncertain times of Covid-19, when the “modern” world appears more fissured than ever, leaving its “others” to fend for themselves; the Nicobarese’s group has set an example for everyone to follow.     

The Local Life of Nationhood

What characterises many studies that invoke the local can be described as a logic of transcendence. This logic of transcendence does not reject nor disregard the local. Rather, it affirms the centrality of the local. At the same time, the focus is on how the local is historically transcended into higher levels of generality and abstraction; the argument is that only through attention to these higher levels that the meanings of the local become clear. In contrast, the other local which we refer to in this essay is a set of practices which emerges in intimate relationship to nationalism, which in some ways even sustains nationalism, even though the places it produces cannot be understood within the same logic of transcendence. At times, this other local refers to the political and conceptual practices that emerged at the limits of the abstract time and space that constituted nationalism. At other times, this local refers to the marginal in order to represent nationhood anew. Nationhood does not exhaust, sublate or transcend this local; rather, this local continues to live, in the era of nationhood, not so much outside the national, but beyond and alongside it. This other local is explored in this essay by discussing the cases of Germany and India.     

Multilevel particle filters for the non-linear filtering problem in continuous time

Statistics and Computing - In the following article we consider the numerical approximation of the non-linear filter in continuous-time, where the observations and signal follow diffusion...     

Bayesian inference for stable Lévy–driven stochastic differential equations with high‐frequency data

In this paper, we consider parametric Bayesian inference for stochastic differential equations driven by a pure‐jump stable Lévy process, which is observed at high frequency. In most cases of practical interest, the likelihood function is not available; hence, we use a quasi‐likelihood and place an associated prior on the unknown parameters. It is shown under regularity conditions that there is a Bernstein–von Mises theorem associated to the posterior. We then develop a Markov chain Monte Carlo algorithm for Bayesian inference, and assisted with theoretical results, we show how to scale Metropolis–Hastings proposals when the frequency of the data grows, in order to prevent the acceptance ratio from going to zero in the large data limit. Our algorithm is presented on numerical examples that help verify our theoretical findings.     

Cross‐training Decisions in Field Services with Three Job Types and Server–Job Mismatch*

To be cost‐effective, field service managers must balance the high cost of machine downtime with the high cost of cross‐training technicians in multiple skills. We study a field service system with three job types requiring three different skills. Each server has a primary skill, the cost of which is considered sunk, and up to two secondary skills, which is a managerial decision. We model two important characteristics that distinguish field services: server–job mismatch and the ratio of travel time to service time. We use a queueing framework and simulation to study three cross‐training decisions: the number of servers cross‐trained in secondary skills, the number of secondary skills each server should have, and the efficiency in each secondary skill. We find that complete cross‐training is cost‐effective in some field service situations. Typically, efficiency in secondary skills must be close to 100%, but when the probability of mismatch is high and the ratio of travel time to service time is high, efficiency in secondary skills must be less than 100%.     

The Price Chameleons Pay: Self‐monitoring,Boundary Spanning and Role Conflict in the Workplace*

The vast majority of research on self‐monitoring in the workplace focuses on the benefits that accrue to chameleon‐like high self‐monitors (relative to true‐to‐themselves low self‐monitors). In this study, we depart from the mainstream by focusing on a potential liability of being a high self‐monitor: high levels of experienced role conflict. We hypothesize that high self‐monitors tend to choose work situations that, although consistent with the expression of their characteristic personality, inherently involve greater role conflict (i.e. competing role expectations from different role senders). Data collected from a 116‐member high‐tech firm showed support for this mediation hypothesis: relative to low self‐monitors, high self‐monitors tended to experience greater role conflict in work organizations because high self‐monitors were more likely to occupy boundary spanning positions. To help draw a more realistic and balanced portrait of self‐monitoring in the workplace, we call for more theoretically grounded research on the price chameleons pay.