Patterns of im/mobility,conflict and the re/making of identity narratives*

ABSTRACT

This paper analyses the interrelationship between patterns of im/mobility on the one hand and the reconstitution of social collective identities and the related emergence or settlement of conflicts on the other. The main arguments are (1) that the im/mobility of a social or cultural group has major impact on how identity narratives, a sense of belonging and relationships to ‘others’ are shaped, and vice versa, and (2) that these dynamics are closely interlinked with mechanisms of inclusion and exclusion between groups and power structures that involve a broad variety of actors. Mainly looking at patterns of internal mobility such as ‘traditional’ or strategic mobilities and mobilities enforced by crisis, conflict or governmental programmes and regimes, the contribution provides the conceptual background for a special issue that aims to go beyond currently predominant issues of transnational migration. Established or emerging dynamics of (non-)integration and belonging, caused by im/mobility, are analysed on a cultural and political level, which involves questions of representation, indigeneity/autochthony, political rights and access to land and other resources. Conflict situations in contexts of mobility involve changes in the social understanding and renegotiation, reconstruction or reproduction of group identities and narratives with reference to certain socio-political and historical patterns. The legitimation of rights and access to various forms of citizenship and mobility need to be understood against the backdrop of emerging or established mechanisms of inclusion and exclusion between groups, which trigger or settle conflicts and make social identities to be constantly renegotiated.     

Interpreting conflict and integration through the reciprocity lens: mobility and settlement in a historical perspective on the Sierra Leonean coast

ABSTRACT

In recent years, Sierra Leone has witnessed intense population movements. During the civil war (1991–2002), many populations fled the fighting zones of the interior to take refuge on the coast. Since the conflict ended, new populations have reached the coastal area with the hope of accessing economic opportunities in the fishing business. Mobility, along with changing sociopolitical and economic conditions, has generated conflict between immigrants and Sherbro populations, who consider themselves autochthonous and deny migrants the freedom to access political and land rights. The paper argues that present dynamics of conflicts are rooted in long-term patterns of settlement and relationships of reciprocity between groups. Relations between migrants and local populations are grounded in a sociocultural idiom that implies the institutionalization of practices of reciprocity between local inhabitants (hosts) and later settlers (strangers). The host/stranger reciprocity system is an emic model of cultural action embedded in historical and power relations between groups. It implies the progressive integration of strangers into the host society. This paper highlights how, in a situation of conflict, long-established social relationships between groups are reevaluated with reference to norms of integration and reciprocity. The paper draws on Sherbro oral traditions to show how social memories about interethnic relations are reframed with reference to values and expectations of reciprocity, in order to explain the recent conflict that opposes Sherbros to immigrants. Sherbros use oral traditions to interpret these tensions in a long-term perspective, thereby expressing their own view on settlement, conflict and integration.     

Evaluating the Temporal Location of Feedback: Providing Feedback Following Performance vs. Prior to Performance

In order to make feedback as effective as possible, it is important to understand its function in the three-term contingency (TTC) and the impact of various factors involved in delivering feedback. Timing of feedback is one factor that can affect the impact of feedback on learner’s behavior. An analysis of timing of feeback may help us getting closer to better understanding how feedback functions in the TTC. The purpose of this study was to evaluate the effects of feedback at different temporal locations. Specifically, feedback was provided either immediately (a) after a teaching session or (b) before the following teaching session, on teaching performance of undergraduate psychology students. The results indicated that feedback provided before the teaching session was more effective in improving teaching skills than feedback that was provided after the session. These findings suggest that feedback may function primarily as an antecedent to future performance and not necessarily as a consequence for past performance. However, the behavioral mechanism that explains these results is not yet clear. Future studies should investigate this further by manipulating the content of feedback prior to the teaching performance.     

Coordination in a Single‐Supplier,Multi‐Retailer Distribution System: Supplier‐Facilitated Transshipments

We consider supplier‐facilitated transshipments for achieving supply chain coordination in a single supplier, multi‐retailer distribution system with non‐cooperative retailers. The previous transshipment literature has focused on coordination through retailer‐negotiated transshipments and thus does not consider the supplier's decision‐making. In contrast, in this study, we assume the supplier is an active participant in the system and we seek to understand how the supplier can facilitate the implementation of coordinating transshipments. We study a two‐period model with wholesale orders at the start of the first period and preventive transshipments performed at the start of the second period. Inspired by a supplier‐facilitated transshipment scheme observed in practice, we assume the supplier implements transshipments through a bi‐directional adjustment contract. Under this contract, each retailer can either buy additional inventory from, or sell back excess inventory to, the supplier. We show that coordination can be achieved through carefully designed contracts with state‐dependent adjustment prices and a wholesale price menu. We demonstrate that the supplier's role in facilitating coordinating transshipments is critical. In addition, we use our understanding of the coordinating contract form to derive some simpler and easier‐to‐implement heuristic contracts. We use a numerical study to demonstrate the value, to the supplier, of using the coordinating adjustment and wholesale prices, and to evaluate the heuristics’ performance.     

Generating a smallest binary tree by proper selection of the longest edges to bisect in a unit simplex refinement

In several areas like global optimization using branch-and-bound methods for mixture design, the unit n-simplex is refined by longest edge bisection (LEB). This process provides a binary search tree. For \(n>2\), simplices appearing during the refinement process can have more than one longest edge (LE). The size of the resulting binary tree depends on the specific sequence of bisected longest edges. The questions are how to calculate the size of one of the smallest binary trees generated by LEB and how to find the corresponding sequence of LEs to bisect, which can be represented by a set of LE indices. Algorithms answering these questions are presented here. We focus on sets of LE indices that are repeated at a level of the binary tree. A set of LEs was presented in Aparicio et al. (Informatica 26(1):17–32, 2015), for \(n=3\). An additional question is whether this set is the best one under the so-called \(m_k\)-valid condition.     

<Emphasis Type="BoldItalic">MAD-STEC</Emphasis>: a method for multiple automatic detection of space-time emerging clusters

Crime or disease surveillance commonly rely in space-time clustering methods to identify emerging patterns. The goal is to detect spatial-temporal clusters as soon as possible after its occurrence and to control the rate of false alarms. With this in mind, a spatio-temporal multiple cluster detection method was developed as an extension of a previous proposal based on a spatial version of the Shiryaev–Roberts statistic. Besides the capability of multiple cluster detection, the method have less input parameter than the previous proposal making its use more intuitive to practitioners. To evaluate the new methodology a simulation study is performed in several scenarios and enlighten many advantages of the proposed method. Finally, we present a case study to a crime data-set in Belo Horizonte, Brazil.     

Testing independence based on Bernstein empirical copula and copula density

In this paper we provide three nonparametric tests of independence between continuous random variables based on the Bernstein copula distribution function and the Bernstein copula density function. The first test is constructed based on a Cramér-von Mises divergence-type functional based on the empirical Bernstein copula process. The two other tests are based on the Bernstein copula density and use Cramér-von Mises and Kullback–Leibler divergence-type functionals, respectively. Furthermore, we study the asymptotic null distribution of each of these test statistics. Finally, we consider a Monte Carlo experiment to investigate the performance of our tests. In particular we examine their size and power which we compare with those of the classical nonparametric tests that are based on the empirical distribution function.     

Improving the detection of unusual observations in high‐dimensional settings

Multivariate control charts are used to monitor stochastic processes for changes and unusual observations. Hotelling's T² statistic is calculated for each new observation and an out‐of‐control signal is issued if it goes beyond the control limits. However, this classical approach becomes unreliable as the number of variables p approaches the number of observations n, and impossible when p exceeds n. In this paper, we devise an improvement to the monitoring procedure in high‐dimensional settings. We regularise the covariance matrix to estimate the baseline parameter and incorporate a leave‐one‐out re‐sampling approach to estimate the empirical distribution of future observations. An extensive simulation study demonstrates that the new method outperforms the classical Hotelling T² approach in power, and maintains appropriate false positive rates. We demonstrate the utility of the method using a set of quality control samples collected to monitor a gas chromatography–mass spectrometry apparatus over a period of 67 days.     

A powerful and efficient algorithm for breaking the links between aliased effects in asymmetric designs

Fractional factorial (FF) designs are no doubt the most widely used designs in experimental investigations due to their efficient use of experimental runs. One price we pay for using FF designs is, clearly, our inability to obtain estimates of some important effects (main effects or second order interactions) that are separate from estimates of other effects (usually higher order interactions). When the estimate of an effect also includes the influence of one or more other effects the effects are said to be aliased. Folding over an FF design is a method for breaking the links between aliased effects in a design. The question is, how do we define the foldover structure for asymmetric FF designs, whether regular or nonregular? How do we choose the optimal foldover plan? How do we use optimal foldover plans to construct combined designs which have better capability of estimating lower order effects? The main objective of the present paper is to provide answers to these questions. Using the new results in this paper as benchmarks, we can implement a powerful and efficient algorithm for finding optimal foldover plans which can be used to break links between aliased effects.