CAN SEARCH‐MATCHING MODELS EXPLAIN MIGRATION AND WAGE AND UNEMPLOYMENT GAPS IN DEVELOPING ECONOMIES? A CALIBRATION APPROACH*

ABSTRACT A recent theoretical literature tries to understand the migration pattern in developing economies through the lens of search‐matching (SM) models, but there has been little empirical support for these models. This paper tries to fill this gap by examining whether the models are consistent with the data from developing economies. Combined with some suggestive statistics, our calibration exercise reveals that when augmented with additional frictions (fixed costs of starting up new businesses and mobility costs), our SM model can account for the data and is at least more consistent with the data than traditional Harris–Todaro models.     

Assessing Measures Designed to Protect the Homeland

Some general parameters are proposed for evaluating homeland security measures that seek to make potential targets notably less vulnerable to terrorist attack, and these are then applied to specific policy considerations. Since the number of targets is essentially unlimited, since the probability that any given target will be attacked is near zero, since the number and competence of terrorists is limited, since target-selection is effectively a near-random process, and since a terrorist is free to redirect attention from a protected target to an unprotected one of more or less equal consequence, protection seems to be sensible only in a limited number of instances.     

Keeping an eye on your pots: the provenance of Neolithic ceramics from the Cave of the Cyclops,Youra, Greece

Combined petrographic and chemical analysis of MN and LN ceramics from the Cave of the Cyclops on the island of Youra, Greece, has revealed a compositionally diverse assemblage with a range of different local and off-island sources. Ceramics deposited in Neolithic times on this barren, rocky outpost of the Sporades chain may have originated from a surprising number of possible origins, including from the Plain of Thessaly, Euboea and the volcanic northeast Aegean islands. This picture challenges traditional assumptions about Neolithic pottery production and indicates that significant movement of ceramics was already taking place within the northern Aegean as early as the beginning of the sixth millennium BC. The discovery of a persistent local pottery tradition, that is also found on the neighbouring island of Kyra-Panagia, indicates significant continuity in ceramic technology over some 1500 years.     

Essentials in the use of mycolic acid biomarkers for tuberculosis detection: response to “High-throughput mass spectrometric analysis of 1400-year-old mycolic acids as biomarkers for ancient tuberculosis infection” by

High molecular weight long-chain mycolic acids are key structural components of the cell envelope of Mycobacterium tuberculosis and they are established as biomarkers for the identification of both ancient and modern tuberculosis. Mycolic acids from M. tuberculosis have a characteristic profile, reflecting contributions from five major distinct homologous series of mycolate structural types. Diagnosis of tuberculosis in archaeological material, using mycolic acid biomarkers, depends on objective recognition of the key characteristic mycolic acid components. A recent article in this journal claimed that tuberculosis could be confirmed in ancient bones by high throughput mass spectrometric analysis of mycolic acids. Scrutiny of the data presented reveals no convincing evidence for the presence of mycolic acids, characteristic of the M. tuberculosis complex, in the skeletal remains examined. This communication reviews the essential criteria necessary for positive tuberculosis diagnosis, using mycolic acids.     

Experimental analysis of the practical limits of lithic refitting

We report on the results of an experiment aimed at determining the effects of experience/aptitude, lithic reduction type (biface v. core), and flake size cut-offs on different rates of success in refitting studies. We found that experience matters, but that there can be large differences in aptitude for refitting; that cores are easier to refit than bifaces; and that the effort of refitting increases considerably for flakes smaller than 5–6 g. We propose the use of an asymptotic equation fit to a cumulative curve as a way to determine when a study has reached the point of diminishing returns for a given flake size cut-off, and to help determine differences in aptitude for refitting.     

Amplification and sequencing of Trichuris trichiura ancient DNA extracted from archaeological sediments

Despite high prevalence of Trichuris trichiura infection, PCR-based analysis on T. trichiura from archaeological samples has not been established so far. In the present study, we sought to perform PCR-based amplification of T. trichiura aDNA using the sediments from medieval tomb of Korea. The presence of Trichuris eggs were first detected by microscopic observation; then confirmed by PCR-based aDNA analysis. Obtained sequence showed 100% homology to that of the small subunit ribosomal RNA (SSUrRNA) gene of T. trichiura but distinct from that of other Trichuris species. PCR-based aDNA analysis in this study can serve as effective method to confirm the presence of T. trichiura eggs in the soils or coprolites collected from archaeological sites.     

Mad cow militancy: Neoliberal hegemony and social resistance in South Korea

Massive protests shook South Korea through the summer of 2008. This political eruption which exhibited many novel and unexpected elements cannot be explained by pointing to basic political conditions in South Korea (strong labor unions, democratization, and so forth). Neither does the putative reason for them – to protest the new President’s decision to reopen South Korea’s beef market to the U.S. – adequately explain the social dynamics at play. In this paper, we examine the political geography of the ‘candlelight protests’ (as they came to be known), focusing in particular on their novel aspects: the subjectivities of the protesters, fierce ideological struggles, and differentiated geography. We argue that the deepening of neoliberal restructuring by the new conservative regime formed the underlying causes of these intense conflicts. In other words, the new protests should be seen as a response to the reinforced contradictions engendered by neoliberalization and a new alignment of social groups against the prevailing hegemonic conditions in South Korea. In this view, the huge demonstrations revealed vulnerabilities in conservative hegemony but failed to produce a different hegemony. To advance these claims, we examine three aspects of the protests: first, the neoliberal policies of the new conservative regime; second, the intense ideological conflicts around the media; and finally, the spatial materialization of the protests.     

Consideration of Proximity in Selection of Residential Location by Science and Technology Workers: Case Study of Hsinchu,Taiwan

The Hsinchu district has been one of the most rapidly developing areas of Taiwan during the past decade. The rise of the Hsinchu Science-based Industrial Park (HSIP) has significantly influenced population growth and living environment in the Hsinchu district. To obtain new knowledge via knowledge proliferation activities that occur following knowledge innovation, science and technology workers have been established based on the proximity of informal social network interactions and the existence of a common culture. Based on social, identified and cognitive proximities, this investigation examines whether science and technology workers directly assess their living environment while considering housing purchases, seeking information and making residential location decisions. This investigation employs regression analysis to examine the correlation between individual proximity factors and spatial proximity, based on the hypothesis that individual proximity influences residential location choices of science and technology communities. The study results indicate that the housing choice behaviours of the science and technology community follow two proximity paths, that is, internal and external proximity factors. Consequently, the pull created by individual proximity has slowed the spatial expansion of the Hsinchu region.     

Quantifying tomb geometries in resistivity images using watershed algorithms

Quantifying the geometries (defined here as width, height and depth of burial) of archeological structures within resistivity models produced as a result of the regularization constraints used in most inversion algorithms is difficult, especially when structures are closely spaced. Here we apply the watershed by simulated immersion method of boundary detection to smooth 2D resistivity images generated for synthetic and field data over 3D targets. The synthetic studies include a single cavity model, a model for two widely spaced cavities (spacing ? unit electrode spacing) and a model for two closely spaced cavities (spacing < unit electrode spacing). We also examine a single-cavity model where a relatively resistive overburden, common at archaeological sites in Egypt, is included. In the case of the single cavity models, the maximum error for any geometries are 18% for the model without the resistive overburden and 10% for the model where the overburden is included, whereas it increases to 24% for the widely spaced model and 40% for the closely spaced model. Despite, the higher errors in the closely spaced cavity model, application of the algorithm confirms the presence of two features, which is not ascertainable from the smooth resistivity images. Boundaries detected with the watershed algorithm are subsequently used to define a disconnect in the regularization, resulting in a markedly improved estimate of the resistivity structure (particularly for the closely spaced cavity model) in a second inversion step using the model obtained from the smoothness constraint inversion as the starting model. This revised resistivity model also results in a lower root-mean-square (rms) misfit between measured and theoretical data, and between synthetic and inverted models. We demonstrate how the method can be applied on images from the archaeological site at Qurnet Murai, Luxor City Egypt.