Transport Costs and the Size Distribution of a Linearly Arranged System of Cities

The question regarding the effects of changing transports costs on the size distribution of cities is an important topic of systems of cities research. The so-called New Economic Geography has already given some answers to this question. One central assumption in this kind of model is a very particular, simplified spatial structure. This contribution investigates the consequences of changing transport costs for a system of cities that are located equidistantly on a straight line. In the case of rising transport costs, the main outcome of this model is worker concentration in the central large cities, while the peripheral regions lose residents.transport costs, agglomeration, urban systems

Von der Bezirks- zur Landeshauptstadt: Zum Einfluss der Zuordnung staatlicher Funktionen auf das ostdeutsche Städtesystem

20 years after the German unification, one may ask what consequences for the system of East German cities follow from the changes of the institutional framework. It may be expected that gains or losses of a location in the hierarchy of central places significantly affect the outcome of economic activity as well as the accumulation of – particularly human – capital. The reorganisation of countries on the territory of the former GDR that has elevated five former district capitals to the status of state capitals while the other ones became urban municipalities has created a model case whose implications were investigated by the IWH. The main objective was to identify a pattern of group formation within the former district capitals on the basis of socioeconomic indicators that coincides with the subgroups out of them with and without the status of a capital state. By means of cluster analysis, we have found that already from 1995 to 2000, differences between both groups with regard to income, structure of employment, human capital, and other indicators were significantly. In the period from 2002 to 2007, the spread of income is growing not only between both groups but also within the group of state capitals, dividing their cluster. We can conclude that the allocation of political institutions of higher centrality has influence on local economic development.

Befindet sich die "Metropolregion Mitteldeutschland" auf dem Weg zur räumlich integrierten Region? Eine empirische Untersuchung der Berufspendlerverflechtungen

Die "Metropolregion Mitteldeutschland" war von 2009 bis 2013 als Städtenetzwerk von elf Städten verfasst, eingebettet in die drei ostdeutschen Länder Sachsen, Sachsen-Anhalt und Thüringen. Erwartet wurden eine Stärkung der Synergieeffekte zwischen den Städten durch interkommunale Kooperation und die Entstehung einer polyzentrischen Metropolregion. Mithilfe eines doppelt beschränkten Gravitationsmodells werden im vorliegenden Beitrag die Pendlerverflechtungen zwischen den elf Städten einschließlich der sie umschließenden funktionalen Regionen untersucht. Es zeigt sich, dass die Intensität des beruflichen Pendelns nicht nur von der Entfernung, sondern auch von der Existenz einer Landesgrenze zwischen den Städten beeinflusst wird. Dies deutet darauf hin, dass eine länderübergreifende interkommunale Kooperation auch vom Verhalten der Länder beeinflusst wird. Auch dürften die besten Bedingungen für eine Zusammenarbeit der Städte im geografischen Zentrum der Region gegeben sein.From 2009 until 2013, the Central German Metropolitan Region was a network of eleven cities, located in the three East-German states of Saxony, Saxony-Anhalt and Thuringia. It was founded to bring the bundled strengths of these cities into a powerful inter-municipal cooperation, for becoming a polycentric metropolitan area. To assess this ambitious project, the contribution analyses in the framework of a doubly constrained gravity model the commuting relations between the eleven cities including their surrounding functional regions. It is shown that commuting relations are determined not only by distance, but also by the state borders that cross the area. This suggests that cooperation between the eleven core cities could be more successful if the three states are willing to support the cooperation. Furthermore, empirical results suggest that best conditions for inter-municipal cooperation are given for cities in the geographical centre of the area

Transportkosten und Städtesystem

Die mittleren Kosten des Gütertransports in einer Volkswirtschaft gehören zu jenen Faktoren, die maßgeblich an der Ausformung ihres Städtesystems mit beteiligt sind. Der Beitrag geht der Frage nach, welche Effekte Transportkostenänderungen (hierbei kann es sich sowohl um einen Rückgang als auch um einen Anstieg handeln) auf das Städtesystem ausüben können. Dabei finden unterschiedliche Modelle Anwendung, die auf Grundannahmen der Neuen Ökonomischen Geographie aufbauen. Die spezifischen Annahmen dieser Modelle werden miteinander verglichen, ihre Ergebnisse einander gegenübergestellt. Es zeigt sich, dass die auf teilweise sehr restriktiven Annahmen aufgebauten Modellergebnisse sich in ihren Aussagen scheinbar widersprechen bzw. dass eine Interpretation dieser Modelle nur im Hinblick auf ihre spezifischen Fragestellungen vorgenommen werden darf. Hierzu gehören Suburbanisierungstendenzen, die Erschließung peripherer Regionen und die Konzentration der Führungszentralen von Unternehmen.The average costs of transporting goods in a national economy are one of the factors that significantly contribute towards the shaping of the urban system. This paper pursues the question of what effect changes in transport costs (this can include a reduction as well as an increase) can have on the urban system. Various models based on the fundamental assumptions of New Economic Geography are applied. The specific assumptions of these models are compared with one another and their results contrasted. It is demonstrated that the modelling results, which in some cases are based upon very restrictive assumptions, appear to contradict one another in terms of their findings, or, alternatively, that the findings of these models should only be interpreted with regard to the specific questions that each pose. These include suburbanisation tendencies, the opening up of peripheral regions, and the concentration of company headquarters

Kosten der Raumüberwindung

Kosten der Raumüberwindung fassen Aufwendungen zusammen, die bei der Überwindung von Distanzen im Raum entstehen und bei der Nutzung von Netzinfrastrukturen anfallen. Sie beschränken Mobilität, Erreichbarkeit (von Orten) und Aktualität (von Informationen) und können Raumstrukturen beeinflussen

Ausbau der kommunalen Tourismus-Infrastruktur in Sachsen: Positive Effekte in Urlaubsorten mit Tradition, Chancen für Newcomer sind begrenzt

In vielen ostdeutschen Kommunen werden vor dem Hintergrund des Zusammenbruchs alter Industrien und der noch immer hohen Arbeitslosigkeit große Hoffnungen in die Möglichkeit gesetzt, den Tourismussektor als Motor für die lokale wirtschaftliche Entwicklung zu nutzen. Demgemäß wurden und werden von zahlreichen ostdeutschen Kommunen Investitionen in die Tourismus-Infrastruktur durchgeführt, um die Attraktivität der Orte für den Fremdenverkehr zu steigern und die Beschäftigung im Gastgewerbe zu erhöhen. Bund und Länder unterstützen diese kommunalen Investitionen nicht zuletzt über Zuschüsse für den Infrastrukturausbau im Rahmen der „Gemeinschaftsaufgabe zur Verbesserung der regionalen Wirtschaftsstruktur“ („GA-Infra-Förderung“). Der Beitrag untersucht am Beispiel der GA-InfraFörderung in Sachsen die Frage, ob bislang wenig touristisch orientierte Kommunen eine Chance haben, sich mit Hilfe des Ausbaus ihrer Infrastruktur zu relevanten touristischen Destinationen zu entwickeln, oder ob die positiven Effekte von infrastrukturellen Maßnahmen vor allem an den „klassischen“ Tourismusorten anfallen. Im Theorieteil des Beitrags werden die Faktoren herausgearbeitet, die für die erfolgreiche touristische Entwicklung einer Kommune von Bedeutung sind. Es wird gezeigt, dass hierbei Lokalisations- und Urbanisationseffekte und mithin lokale Pfadabhängigkeiten eine große Rolle spielen. Dies spricht dafür, dass sich die lokale Tourismuswirtschaft allein durch Investitionen in die Infrastruktur nicht positiv entwickeln kann. Diese Vermutung wird durch die empirischen Ergebnisse weitgehend bestätigt, die auf einer ökonometrischen Schätzung sowie ergänzenden Befragungen beruhen. Dabei erfolgt eine Differenzierung zwischen den sächsischen Kommunen gemäß ihrer bisherigen Nähe zum Tourismus. Es zeigt sich auch, dass „Newcomer“-Kommunen nur dann eine Chance haben, wenn sie in massivem Umfang größere Infrastrukturprojekte realisiert haben. Für die Förderpolitik des Staates gegenüber den Kommunen folgt daraus, die Mittel gemäß dem Motto „Stärken stärken“ zukünftig noch stärker räumlich zu konzentrieren – auf die traditionellen Destinationen oder auf besonders erfolgversprechende Großprojekte.

Was bringen Vernetzung und Kooperation für die lokale Wirtschaftsentwicklung? - Bericht über eine Tagung am IWH

The Department of Urban Economics of the Halle Institute for Economic Research (IWH) held on 2 and 3 December 2010 the third “Halle Forum on Urban Economic Growth“. The biennial “Halle Forum” focuses on the determinants of urban growth. This year's conference addressed the forms and benefits of cooperation and networking for the economic development of cities and metropolitan regions. The presentations and discussions focused on the one hand on the effects and determinants of inter-and intra-regional cooperation between firms, and on the other hand on cooperation between neighboring municipalities, especially through the establishment of metropolitan regions.

COLD GASS, an IRAM legacy survey of molecular gas in massive galaxies: I. Relations between H2, HI, stellar content and structural properties

We are conducting COLD GASS, a legacy survey for molecular gas in nearby galaxies. Using the IRAM 30m telescope, we measure the CO(1-0) line in a sample of ~350 nearby (D=100-200 Mpc), massive galaxies (log(M*/Msun)>10.0). The sample is selected purely according to stellar mass, and therefore provides an unbiased view of molecular gas in these systems. By combining the IRAM data with SDSS photometry and spectroscopy, GALEX imaging and high-quality Arecibo HI data, we investigate the partition of condensed baryons between stars, atomic gas and molecular gas in 0.1-10L* galaxies. In this paper, we present CO luminosities and molecular hydrogen masses for the first 222 galaxies. The overall CO detection rate is 54%, but our survey also uncovers the existence of sharp thresholds in galaxy structural parameters such as stellar mass surface density and concentration index, below which all galaxies have a measurable cold gas component but above which the detection rate of the CO line drops suddenly. The mean molecular gas fraction MH2/M* of the CO detections is 0.066+/-0.039, and this fraction does not depend on stellar mass, but is a strong function of NUV-r colour. Through stacking, we set a firm upper limit of MH2/M*=0.0016+/-0.0005 for red galaxies with NUV-r>5.0. The average molecular-to-atomic hydrogen ratio in present-day galaxies is 0.3, with significant scatter from one galaxy to the next. The existence of strong detection thresholds in both the HI and CO lines suggests that "quenching" processes have occurred in these systems. Intriguingly, atomic gas strongly dominates in the minority of galaxies with significant cold gas that lie above these thresholds. This suggests that some re-accretion of gas may still be possible following the quenching event.Comment: Accepted for publications in MNRAS. 32 pages, 25 figure

COLD GASS, an IRAM Legacy Survey of Molecular Gas in Massive Galaxies: II. The non-universality of the Molecular Gas Depletion Timescale

We study the relation between molecular gas and star formation in a volume-limited sample of 222 galaxies from the COLD GASS survey, with measurements of the CO(1-0) line from the IRAM 30m telescope. The galaxies are at redshifts 0.025<z<0.05 and have stellar masses in the range 10.0<log(M*/Msun)<11.5. The IRAM measurements are complemented by deep Arecibo HI observations and homogeneous SDSS and GALEX photometry. A reference sample that includes both UV and far-IR data is used to calibrate our estimates of star formation rates from the seven optical/UV bands. The mean molecular gas depletion timescale, tdep(H2), for all the galaxies in our sample is 1 Gyr, however tdep(H2) increases by a factor of 6 from a value of ~0.5 Gyr for galaxies with stellar masses of 10^10 Msun to ~3 Gyr for galaxies with masses of a few times 10^11 Msun. In contrast, the atomic gas depletion timescale remains contant at a value of around 3 Gyr. This implies that in high mass galaxies, molecular and atomic gas depletion timescales are comparable, but in low mass galaxies, molecular gas is being consumed much more quickly than atomic gas. The strongest dependences of tdep(H2) are on the stellar mass of the galaxy (parameterized as log tdep(H2)= (0.36+/-0.07)(log M* - 10.70)+(9.03+/-0.99)), and on the specific star formation rate. A single tdep(H2) versus sSFR relation is able to fit both "normal" star-forming galaxies in our COLD GASS sample, as well as more extreme starburst galaxies (LIRGs and ULIRGs), which have tdep(H2) < 10^8 yr. Normal galaxies at z=1-2 are displaced with respect to the local galaxy population in the tdep(H2) versus sSFR plane and have molecular gas depletion times that are a factor of 3-5 times longer at a given value of sSFR due to their significantly larger gas fractions.Comment: Accepted for publication in MNRAS. 19 pages, 11 figure

Millimeter imaging of submillimeter galaxies in the COSMOS field: Redshift distribution

We present new IRAM PdBI 1.3mm continuum observations at ~1.5" resolution of 28 SMGs previously discovered with the 870um bolometer LABOCA at APEX within the central 0.7deg2 of the COSMOS field. 19 out of the 28 LABOCA sources were detected with the PdBI at a >~3sigma level of ~1.4mJy/b. A combined analysis of this new sample with existing interferometrically identified SMGs in the COSMOS field yields the following results: 1) >~15%, and possibly up to ~40% of single-dish detected SMGs consist of multiple sources, 2) statistical identifications of multi-wavelength counterparts to the single-dish SMGs yield that only ~50% of these single-dish SMGs have real radio or IR counterparts, 3) ~18% of interferometric SMGs have only radio or even no multi-wavelength counterpart at all, and 4) ~50-70% of z>~3 SMGs have no radio counterparts down to an rms of 7-12uJy at 1.4GHz. Using the exact interferometric positions to identify proper multi-wavelength counterparts allows us to determine accurate photometric redshifts for these sources. The redshift distributions of the combined and the individual 1.1mm and 870um selected samples have a higher mean and broader width than the redshift distributions derived in previous studies. Our sample supports the previous tentative trend that on average brighter and/or mm-selected SMGs are located at higher redshifts. There is a tentative offset between the mean redshift for the 1.1mm (=3.1+/-0.4) and 870um (=2.6+/-0.4) selected samples, with the 1.1mm sources lying on average at higher redshifts. Based on our nearly complete sample of AzTEC 1.1mm SMGs within a uniform 0.15deg2 area we infer a higher surface density of z>~4 SMGs than predicted by current cosmological models. In summary, our findings imply that (sub-)millimeter interferometric identifications are crucial to build statistically complete and unbiased samples of SMGs.Comment: 35 pages, 18 figures, 10 tables; accepted for publication in A&