René Königs beitrag zur Soziologie in Deutschland

Ohne Zusammenfassung Rede zum 100. Geburtstag auf einer Veranstaltung der Stadt K?ln, der René-K?nig-Gesellschaft und des Westdeutschen Rundfunks K?ln am 11. Mai 2006 in K?ln     

Anmerkungen zur Publikation „Möglichkeiten und Probleme des Einsatzes postalischer Befragungen“ von Karl-Heinz Reuband in der Kzfss 2001, 2, S. 307–333

Reuband’s article purports to report empirical results that seem to contradict the widely held view of mail surveys. This assertion is made possible only by an unclear statement of hypotheses and a selective perception of the literature. The data analysis is based on techniques from the 1960s and 1970s; modern methods are not even mentioned. Although all the results reported in the article are based on local surveys conducted by a university institute, these are generalized to national surveys in general. The main points of this critique are methodological: careless literature review, lack of concrete hypotheses, inefficient data analysis and generalizations without empirical foundation.     

Historical regional patterns of infant mortality in Austria

First an overview is given of the secular decline of infant mortality in Austria between 1820 and 1950 is given. Second the study analyses the historical regional differences of infant mortality in Austria comparing data for all 99 political districts (Politische Bezirke) for the period 1900 to 1950. The most important results are: At the turn of the 19th century infant mortality rates were generally lower in Alpine than in non-alpine regions and lower in cities than in their surrounding areas. This geographical pattern which remained constant until the 1950s was solely determined by differences in post-neonatal mortality rates. Plausible explanations for these regional differences are discussed.En premier lieu cette étude fournit une vue d'ensemble du déclin séculaire de la mortalité infantile en Autriche en 1820 et 1950. Elle analyse ensuite les différences régionales de mortalité infantile en comparant les données des 99 districts politiques (Politische Bezirke) autrichiens, de 1900 à 1950. Les principaux résultats sont les suivants: à la fin du XIX^e siècle les taux de mortalité infantile étaient en général plus faibles dans les régions alpines que dans les autres et plus faibles dans les villes que dans les aires adjacentes. Ce modèle géographique, qui est resté le même jusqu'en 1950, était uniquement déterminé par les différences entre les taux de mortalité post-néonatale. Des explications plausibles de ces différences régionales sont discutées ici.     

A count data model for gamma waiting times

A new distribution for non-negative integers, or counts, is developed. It is based on the assumption that the waiting times separating consecutive events are independently and identically gamma distributed. Thus, the structural process generating the counts may exhibit duration dependence. In this framework, the frequently observed phenomenon of overdispersion, that is a variance that exceeds the mean, is caused by a decreasing hazard function of the gamma distributed waiting times, while an increasing hazard leads to underdispersion at the level of the counts. A Monte Carlo simulation and an application to fertility data illustrate the performance of the new distribution.     

Optional citizenship; articulation of interests and identities in naturalisations

Citizenship should be understood as a bundle of rights rather than as a legal expression of national membership. The citizenship status of immigrants is characterised by their human rights, their rights of external citizenship provided by sending countries, and their rights as resident aliens provided by receiving states. In this perspective naturalisation is only one amongst several options open to migrants to change and improve their legal position. The normative aspect of citizenship implies that general and basic rights should be distributed equally and universally within society. Raising the standard of alien rights, allowing for dual citizenship and conceiving of naturalisation as an individual option rather than as an obligation or as a discretionary decision of the receiving state would contribute to a more equal distribution of rights within societies of immigration. A model for explaining individual decision to naturalise is presented which is based on a combined analysis of interests and identities. The main factors that enter the model are rules applied by state authorities, social positions occupied by immigrants, the cost/benefit balance of rights in the transition to internal citizenship, and affiliations to different communities in the sending and the receiving state. The combination of rules, rights and social positions makes it possible to distinguish an objective value of internal citizenship for immigrants from transaction prices and subjective utilities. The main theoretical argument is that decisions can be influenced both by a perception of rational individual interests and by communal identities.     

Improving the use of self-generated identification codes

In panel studies on sensitive topics, respondent-generated identification codes are often used to link records across surveys. However, usually a substantial number of cases are lost due to the codes. These losses may cause biased estimates. Using more components and linking the codes by the Levenshtein string distance function will reduce the losses. In a simulation study and two field experiments, the proposed procedure outperforms the methods previously applied.     

An Advanced Heuristic for Multiple‐Option Spare Parts Procurement after End‐of‐Production

After‐sales service is a major source of profit for many original equipment manufacturers in industries with durable products. Successful engagement in after‐sales service improves customer loyalty and allows for competitive differentiation through superior service like an extended service period during which customers are guaranteed to be provided with service parts. Inventory management during this period is challenging due to the substantial uncertainty concerning demand over a long time horizon. The traditional mechanism of spare parts acquisition is to place a large final order at the end of regular production of the parent product, causing major holding costs and a high level of obsolescence risk. With an increasing length of the service period, more flexibility is needed and can be provided by adding options like extra production and remanufacturing. However, coordinating all three options yields a complicated stochastic dynamic decision problem. For that problem type, we show that a quite simple decision rule with order‐up‐to levels for extra production and remanufacturing is very effective. We propose a heuristic procedure for parameter determination which accounts for the main stochastic and dynamic interactions in decision making, but still consists of relatively simple calculations that can be applied to practical problem sizes. A numerical study reveals that the heuristic performs extremely well under a wide range of conditions, and therefore can be strongly recommended as a decision support tool for the multi‐option spare parts procurement problem. A comparison with decision rules adapted from practice demonstrates that our approach offers an opportunity for major cost reductions.     

Median problems with positive and negative weights on cycles and cacti

This paper deals with facility location problems on graphs with positive and negative vertex weights. We consider two different objective functions: In the first one (MWD) vertices with positive weight are assigned to the closest facility, whereas vertices with negative weight are assigned to the farthest facility. In the second one (WMD) all the vertices are assigned to the nearest facility. For the MWD model it is shown that there exists a finite set of points in the graph which contains the locations of facilities in an optimal solution. Furthermore, algorithms for both models for the 2-median problem on a cycle are developed. The algorithm for the MWD model runs in linear time, whereas the algorithm for the WMD model has a time complexity of  O(n²)\mathcal{O}(n^{2}) .