Deep Uncertainties in Sea-Level Rise and Storm Surge Projections: Implications for Coastal Flood Risk Management

Sea levels are rising in many areas around the world, posing risks to coastal communities and infrastructures. Strategies for managing these flood risks present decision challenges that require a combination of geophysical, economic, and infrastructure models. Previous studies have broken important new ground on the considerable tensions between the costs of upgrading infrastructure and the damages that could result from extreme flood events. However, many risk-based adaptation strategies remain silent on certain potentially important uncertainties, as well as the tradeoffs between competing objectives. Here, we implement and improve on a classic decision-analytical model (Van Dantzig 1956) to: (i) capture tradeoffs across conflicting stakeholder objectives, (ii) demonstrate the consequences of structural uncertainties in the sea-level rise and storm surge models, and (iii) identify the parametric uncertainties that most strongly influence each objective using global sensitivity analysis. We find that the flood adaptation model produces potentially myopic solutions when formulated using traditional mean-centric decision theory. Moving from a single-objective problem formulation to one with multiobjective tradeoffs dramatically expands the decision space, and highlights the need for compromise solutions to address stakeholder preferences. We find deep structural uncertainties that have large effects on the model outcome, with the storm surge parameters accounting for the greatest impacts. Global sensitivity analysis effectively identifies important parameter interactions that local methods overlook, and that could have critical implications for flood adaptation strategies.     

Examining the Global North Migration Policies: A “Push Out – Push Back” Approach to Forced Migration

In this paper we focus on adapting the concept of push – pull factors to forced migration by proposing a “push out – push back” approach that underlines two most crucial elements of forced migrants’ experience. On the one hand, it stresses the reasons for leaving countries of origin or of temporary refuge that are not dependant on the will of people who flew those places, thus the “push out” factors. On the other hand, it represents the refusal of the countries of the Global North to accept forced migrants and their use of various practices, amounting to “push back” factors, to prevent them from entering or leaving their territory if they manage to reach it. These factors can be divided into three groups: passive, active, and symbolic.     

Cox regression with missing covariate data using a modified partial likelihood method

Missing covariate values is a common problem in survival analysis. In this paper we propose a novel method for the Cox regression model that is close to maximum likelihood but avoids the use of the EM-algorithm. It exploits that the observed hazard function is multiplicative in the baseline hazard function with the idea being to profile out this function before carrying out the estimation of the parameter of interest. In this step one uses a Breslow type estimator to estimate the cumulative baseline hazard function. We focus on the situation where the observed covariates are categorical which allows us to calculate estimators without having to assume anything about the distribution of the covariates. We show that the proposed estimator is consistent and asymptotically normal, and derive a consistent estimator of the variance–covariance matrix that does not involve any choice of a perturbation parameter. Moderate sample size performance of the estimators is investigated via simulation and by application to a real data example.     

A Theory of Rational Choice under Ignorance

This paper contributes to a theory of rational choice for decision-makers with incomplete preferences due to partial ignorance, whose beliefs are representable as sets of acceptable priors. We focus on the limiting case of `Complete Ignorance' which can be viewed as reduced form of the general case of partial ignorance. Rationality is conceptualized in terms of a `Principle of Preference-Basedness', according to which rational choice should be isomorphic to asserted preference. The main result characterizes axiomatically a new choice-rule called `Simultaneous Expected Utility Maximization'. It can be interpreted as agreement in a bargaining game (Kalai-Smorodinsky solution) whose players correspond to the (extremal) `acceptable priors' among which the decision maker has suspended judgment. An essential but non-standard feature of Simultaneous Expected Utility choices is their dependence on the entire choice set. This is justified by the conception of optimality as compromise rather than as superiority in pairwise comparisons.     

The FARSEEING real-world fall repository: a large-scale collaborative database to collect and share sensor signals from real-world falls

Background

Real-world fall events objectively measured by body-worn sensors can improve the understanding of fall events in older people. However, these events are rare and hence challenging to capture. Therefore, the FARSEEING (FAll Repository for the design of Smart and sElf-adaptive Environments prolonging Independent livinG) consortium and associated partners started to build up a meta-database of real-world falls.

Results

Between January 2012 and December 2015 more than 300 real-world fall events have been recorded. This is currently the largest collection of real-world fall data recorded with inertial sensors. A signal processing and fall verification procedure has been developed and applied to the data. Since the end of 2015, 208 verified real-world fall events are available for analyses. The fall events have been recorded within several studies, with different methods, and in different populations. All sensor signals include at least accelerometer measurements and 58 % additionally include gyroscope and magnetometer measurements. The collection of data is ongoing and open to further partners contributing with fall signals. The FARSEEING consortium also aims to share the collected real-world falls data with other researchers on request.

Conclusions

The FARSEEING meta-database will help to improve the understanding of falls and enable new approaches in fall risk assessment, fall prevention, and fall detection in both aging and disease.

     

Attitude strength moderates adverse effects to questionnaire design

ABSTRACT

The presentation and visual design of the “don’t know” category in rating scales on respondents’ behavior may have ambivalent effects. The hypothesis is that attitude strength toward the topic influences the respondents’ sensitivity to the graphical design of the scale. A paper-and-pencil questionnaire conducted among 307 German university students contained an experimental variation of the presentation of a “don’t know” category and its visual design. A multinomial logistic regression shows that presenting a “don’t know” category drives respondents toward extreme categories. The visual design of the “don’t know” category influences the distribution of responses, all the more that the respondents’ attitudes toward the item topic are weak.     

Population age structure and consumption growth: evidence from National Transfer Accounts

We assess the effects of the population age structure and the population dynamics on economic growth. Following recent research, we focus on the generational turnover effect to characterize the influence of birth and death rates, depending on the age profile of individual consumption, the extent of annuity market imperfections, and the willingness of households to shift consumption over time. Using data from the National Transfer Accounts on age profiles of consumption for a number of different countries, we assess—in a comparative way—the sign and the magnitude of the generational turnover effect and its impact on economic growth. We find considerable cross-country differences and trace them back to the underlying variation in demography and in the age structure of consumption.     

The Dynamics of Repeat Migration: A Markov Chain Analysis1

This article studies repeat or circular migration between the host and home countries using panel data for Germany, distinguishing between factors generating single moves, circular migration, and absorption. Migrants are more likely to leave early after their first arrival in Germany, and when they have social and familial bonds in the home country, but less likely when they have a job in Germany and speak the language well. Once out‐migrated, the return probability is mainly affected by remittances and family considerations. Circular migration is fostered by vocational training in the host country and older age. Whereas male migrants are 9 percent more likely to return to their home country than female migrants, gender is not significant for predicting the return to move back to Germany.     

Assessment of cognitive workload of in-vehicle systems using a visual peripheral and tactile detection task setting

The increase of driver information and infotainment systems includes also interaction technologies like speech interaction that minimize visual-manual demand and put the focus to cognitive demand. The question is whether this could lead to distraction effects and decreased traffic safety. This study presents an evaluation method for cognitive demand based on different detection paradigms in a dual task setting. A listening and a backward counting task are realized on three difficulty levels as simulations of cognitively loading secondary tasks and investigated using a visual versus a tactile detection paradigm. The results show that both detection paradigms are able to discriminate the task levels and that subjects successfully apply compensation strategies in the dual task setting especially during the listening task.     

Defining elements of sustainable work systems--a system-oriented approach

Based on a system-theoretic discussion of sustainability, this paper aims to develop a conceptual model of a sustainable work system which is consistent with the definition of ergonomics by the IEA in 2000 (but also with earlier definitions) as well as with the triple bottom line understanding of sustainable development - comprising the management of human, social, ecological and economic capital in a balanced manner.