Parasites and Raven Mothers: A German-Japanese Comparison on (Lone) Motherhood

Having a child out of wedlock used to be associated with shame and scorn. This is mostly not the case anymore in the western world. Therefore, freed from social sanctions, single motherhood has become an additional family-choice alternative for women, along with marriage and childlessness. Yet, the institutions that infl uence women’s decisions diff er across countries. We compare the institutional frame, in particular labor-market characteristics and family law, in Germany and Japan and, in addition, the interaction between culture and institutions. Both countries had a very traditional (one-earner) family system until the second half of the 20th century. Now we can observe that social changes that happened in Germany decades ago are happening only now in Japan. We analyze if and how the consequences in terms of family structures and fertility rates that resulted in Germany can be transfered to Japan.Out-of-wedlock childbearing; fertility; family law; Germany; Japan

Parasites and Raven Mothers: A German-Japanese comparison on (lone) motherhood

Having a child out of wedlock used to be associated with shame and scorn. This is mostly not the case any more in the western world. Therefore, freed from social sanctions, single motherhood has become an additional family-choice alternative for women, along with marriage and childlessness. Yet, the institutions that influence women’s decisions differ across countries. We compare the institutional frame, in particular labor-market characteristics and family law, in Germany and Japan and, in addition, the interaction between culture and institutions. Both countries had a very traditional (one-earner) family system until the second half of the 20th century. Now we can observe that social changes that happened in Germany decades ago are happening only now in Japan. We analyze if and how the consequences in terms of family structures and fertility rates that resulted in Germany can be transfered to Japan.

How Much Should an Investor Trust the Startup Entrepreneur? - A Network Model

Trust is an important determinant of start-up financing. In a simple agentbased model it is determined what the best trusting strategy is for a collective of investors and whether it is rational for an individual investor to deviate from this collective optimum. Trust depends on a measure of social distance and is the precondition for investment. Trust increases and decreases based on whether an investor is satisfied with the interest payments received from an entrepreneur. If an investor is dissatisfied, he terminates the relation with the entrepreneur. For assessing the quality of their own investments, investors communicate with other investors in a network-like structure. I find that, as a collective, it is best for investors to compare their returns critically in order to identify unproductive entrepreneurs, but to be tolerant regarding existing links to entrepreneurs in order not to terminate profitable relations because of minor productivity drops. However, it is optimal for an individual investor to deviate from this strategy and to be less easily disappointed, but to decrease trust in larger steps. In a sense, an individual investor can freeride on the others' critical assessment. If all investors behave according to this latter strategy, too many unproductive firms remain in the market and the average investor's return is lower than in the collective optimum.Vertrauen ist ein wichtiger Faktor in der Startup-Finanzierung. In einem einfachen agentenbasierten Modell wird untersucht, welches die beste Vertrauensstrategie für eine Gruppe von Investoren ist, und ob es einen einzelnen Investoren besser stellt, wenn er von diesem kollektiven Optimum abweicht. Anfängliches Vertrauen hängt von sozialer Entfernung ab und ist die Voraussetzung für Investitionen. Vertrauen wächst und schrumpft je nachdem, ob ein Investor mit dem Return, den eher von einem Unternehmer erhält, zufrieden ist. Wenn ein Investor unzufrieden ist, beendet er die Investitionsbeziehung. Um die Höhe ihres eigenen Returns einschätzen zu können, kommunizieren Investoren in einer netzwerkartigen Struktur miteinander. Ich zeige, dass es für Investoren als Kollektiv am besten ist, Returns kritisch zu vergleichen um unproduktive Unternehmer zu identifizieren, dann aber Vertrauen nur in kleinen Schritten zu verlieren, um profitable Beziehung nicht wegen geringfügiger negativer Produktivitätsschocks zu beenden. Ein einzelner Investor kann sich jedoch besser stellen, indem er von dieser Strategie abweicht und weniger leicht enttäuscht ist, dafür aber Vertrauen bei Enttäuschung schnell verliert. Gewissermaßen können individuelle Investoren die kritische Bewertung durch die anderen ausnutzen, weil sichergestellt ist, dass unproduktive Unternehmer ohnehin nicht bestehen. Wenn sich allerdings alle Investoren so verhalten, verbleiben zu viele unproduktive Unternehmer im Markt und der durchschnittliche Return der Investoren ist geringer als im kollektiven Optimum

Parasites and Raven Mothers: A German-Japanese comparison on (lone) motherhood

Having a child out of wedlock used to be associated with shame and scorn. This is mostly not the case any more in the western world. Therefore, freed from social sanctions, single motherhood has become an additional family-choice alternative for women, along with marriage and childlessness. Yet, the institutions that influence women’s decisions differ across countries. We compare the institutional frame, in particular labor-market characteristics and family law, in Germany and Japan and, in addition, the interaction between culture and institutions. Both countries had a very traditional (one-earner) family system until the second half of the 20th century. Now we can observe that social changes that happened in Germany decades ago are happening only now in Japan. We analyze if and how the consequences in terms of family structures and fertility rates that resulted in Germany can be transfered to Japan

Computational Economic Modeling of Migration

In this paper an agent-based model of endogenously evolving migrant networks is developed to identify the determinants of migration and return decisions. Individuals are connected by links, the strength of which declines over time and distance. Methodologically, this paper combines parameterization using data from the Mexican Migration Project with calibration. It is shown that expected earnings, an idiosyncratic home bias, network ties to other migrants, strength of links to the home country and age have a significant impact on circular migration patterns. The model can reproduce spatial patterns of migration as well as the distribution of number of trips of migrants. It is shown how it can also be used for computational experiments and policy analysis.In dieser Studie wird ein agentenbasiertes Modell zum Migrationskreislauf mexikanischer Migranten in die USA eingeführt. Es handelt sich um ein vollständig empirisch fundiertes Modell, d.h. alle Parameter basieren auf empirischen Schätzungen. Insbesondere wurden die Koeffizienten der Verhaltensregeln der Individuen mit geläufigen ökonometrischen Methoden geschätzt. Hierbei wurde das Mexican Migration Project (MMP) verwendet, ein großer Haushaltsdatensatz. In einem ersten Schritt wird gezeigt, dass erwartetes Einkommen, eine idiosynkratische Heimatpräferenz und Netzwerkbeziehungen zu anderen Migranten die wichtigsten Determinanten der Migrationsentscheidung von Angehörigen einer Generation mexikanischer Migranten sind. Die Anzahl und Stärke der Beziehungen in das Heimatland beeinflusst hingegen die Rückkehrentscheidung. Es wird zudem gezeigt, dass die Verteilung der Migranten über die Städte der USA hinweg einer Power-Law-Verteilung folgt. Dies wird erklärt durch einen Preferential-Attachment'-Prozess, in dem Migranten häufig die Städte als Zielort wählen, in denen sie Bekannte und Verwandte haben. Die Verteilung der Anzahl der Migrationsbewegungen ist negativ binomialverteilt, was dadurch zu erklären ist, dass es viel wahrscheinlicher ist, dass Migranten nach der ersten Migrationsbewegung eine weitere Migrationsbewegung durchführen, als dass sie das erste Mal migrieren. Der Grund hierfür ist, dass sich die Entscheidung, zum zweiten Mal zu migrieren, stark von der unterscheidet, zum ersten Mal auszuwandern, weil migrationsspezifische Erfahrungen die Entscheidung erleichtern. Das agentenbasierte Modell ist in der Lage, beide Verteilungen und zwei aggregierte Zeitreihen nachzubilden. Daher wird es für geeignet befunden, Politikanalysen durchzuführen. Es wird gezeigt, wie mit Hilfe des Modells der Effekt einer Erhöhung der mexikanischen Löhne und einer Intensivierung der Grenzkontrollen untersucht werden kann

Increasing Colorectal Cancer Testing: Translating Physician Interventions Into Population-Based Practice

Colorectal cancer (CRC) screening in the Medicare population remains low despite Medicare coverage. We describe a population-based effort to increase CRC testing of Medicare enrollees in two States through promotion and distribution of office-based tools to primary care physicians and gastroenterologists. Small increases in colonoscopy test use by primary care physicians were observed, but the differences were not statistically significant. Results in one State were stronger than the other, and two components of the intervention appeared more promising than others. Use of CRC tests can be increased, but additional approaches are needed

Take the money and run? Redemption of a gift card incentive in a clinician survey

Background: Clinician surveys provide critical information about many facets of health care, but are often challenging to implement. Our objective was to assess use by participants and non-participants of a prepaid gift card incentive that could be later reclaimed by the researchers if unused. Methods: Clinicians were recruited to participate in a mailed or online survey as part of a study to characterize women’s primary health care provider attitudes towards breast and cervical cancer screening guidelines and practices (n = 177). An up-front incentive of a $50 gift card to a popular online retailer was included with the study invitation. Clinicians were informed that the gift card would expire if it went unused after 4 months. Outcome measures included use of gift cards by participants and non-participants and comparison of hypothetical costs of different incentive strategies. Results: 63.5$3700, which was less than half of the initial outlay. Since some of the respondents did not redeem their gift cards, the cost of incentives was less than it might have been if we had provided a conditional incentive of $50 to responders after they had completed the survey. Conclusions: Redeemable online gift card codes may provide an effective way to motivate clinicians to participate in surveys

The science of choice: an introduction

Introduction In October 2015, around 30 scholars convened at the Max Planck Institute for Demographic Research (MPIDR) in Rostock to discuss: (a) how individuals and families make decisions about marriage, child-birth, migration, retirement, and other transitions in the life course; and (b) how these decision processes can be operationalized in demographic models. The workshop was organized by the Scientific Panel on Microsimulation and Agent-Based Modelling con- vened by the International Union for the Scientific Study of Population (IUSSP) and by MPIDR. The report of this ‘Science of choice’ workshop and the papers presented are available from the workshop’s website (see IUSSP 2015). The five papers included in this Supplement are revised versions of papers presented at the workshop in Rostock