Öffentliche Wohnraumförderung — auf dem richtigen Weg?

In Germany, in times of extreme low interest rates there is a boom in housing construction, housing demand and housing prices. In order to relieve the housing market, the Federal Government is planning to expand the funding for social housing considerably. Affordable housing has been decreasing in German metropolitan areas in recent years, the same applies to social housing. Meanwhile, the demand for dwellings in the lower and middle price segment is rising, partly due to an increased migration rate. This is why a strong social housing promotion needs to be combined with an effective direct subsidy, such as a dynamic housing allowance. However, the targeting of social housing is highly inaccurate. Thus, it would be better to strengthen housing allowances and to help lowincome households to purchase homes in order to reduce living costs. Nowadays, property credits stabilize the banking sector. However, just a small increase in interest rates could result in a new financial crash. Ever since their foundation, housing cooperatives have created affordable private dwellings and a safe living place for their members. They are able to produce not only tenants but owners of the dwellings. Thus public assistance schemes and subsidies should not exclude housing cooperatives.     

Evaluating development co-operation

Successful development co-operation largely depends on the willingness and capacity of both the donor and the recipient countries to subject joint projects and programmes to periodic and systematic evaluation, and to initiate learning processes. This article examines the current position of evaluation systems in German development co-operation.     

THE EFFECT OF ESTIMATION IN HIGH‐DIMENSIONAL PORTFOLIOS

We study the effect of estimated model parameters in investment strategies on expected log‐utility of terminal wealth. The market consists of a riskless bond and a potentially vast number of risky stocks modeled as geometric Brownian motions. The well‐known optimal Merton strategy depends on unknown parameters and thus cannot be used in practice. We consider the expected utility of several estimated strategies when the number of risky assets gets large. We suggest strategies which are less affected by estimation errors and demonstrate their performance in a real data example. Strategies in which the investment proportions satisfy an L₁ ‐constraint are less affected by estimation effects.     

Fiscal divergence, current account divergence and TARGET2 imbalances in the EMU

Diverging fiscal policy paths, housing booms and diverging unit labour costs were driving forces of rising intra-European current account imbalances, which were underpinned by low interest rates. Since the outbreak of the crisis, the adjustment of intra-EMU current account imbalances has been postponed by a rising divergence of TARGET2 balances, as the repatriation of private international credit and deposit flight from the crisis economies is intermediated by central bank credit. Given that this process has brought the Deutsche Bundesbank into a debtor position to the domestic financial system, the article discusses options for liquidity absorption by the Bundesbank to forestall asset price bubbles in Germany.     

Wechselkurse und Wirtschaftswachstum: ein nicht-linearer Zusammenhang?

Der Euro zeigt sich gegenüber dem Dollar anhaltend stark. Inwieweit wird die Konjunktur in Europa von der aktuellen St?rke der Gemeinschaftsw?hrung in Mitleidenschaft gezogen? Ist die Grenze erreicht, bei der eine weitere Verschlechterung der preislichen Wettbewerbsf?higkeit die deutsche Exportwirtschaft empfindlich treffen würde? Dr. Axel Jochem, 41, Frankfurt; PD Dr. Stefan Reitz, 43, ist Dozent an der Universit?t Gie?en.     

Scenario planning in public policy: Understanding use,impacts and the role of institutional context factors

Scenario planning has formed a growing area of interest on the interface of academia and public and private sector policy-making. While methodological approaches are well covered in the academic literature, less attention has been paid to studying the use, impacts and effectiveness of scenario planning in public policy-making. This article combines preliminary findings from a review of evaluative scenario literature with workshop discussions among scenario practitioners, using environmental relevant policies as a case study. Subject to the nascent evaluative scenario literature, our preliminary findings highlight that scenario planning still is often executed in a rather ad-hoc and isolated manner and is mostly geared towards indirect decision support such as agenda-setting and issue-framing. The slim evidence base aggravates the assessment, but the potential of scenario planning to prepare public policy-making for the uncertainties and surprises of future developments and better manage complex decisions involving conflicting societal interests is clearly not fully utilized. Political and institutional context factors need to be treated with greater care in the future. Making better decisions under conditions of deep uncertainty does not only require rigorous analysis, but also political will and more stable institutional settings and organisational capacities to build up trust and experience with adaptive, flexible process formats. We synthesize our analysis with a discussion of further research needs.     

Die Ökonomik nichtlinearer Tarife am Beispiel Bahnstrom

Nonlinear tariffs such as quantity discounts are common in infrastructure industries. One reason is that nonlinear tariffs enhance efficiency compared to linear pricing schemes. An example is the nonlinear tariff for the all-inclusive 16,7-Hz Traction Power Supply. Linear tariffs would lead to inefficiently high total costs and to inefficiently low utilization of the infrastructure. In fact, both a perfectly informed price regulation and competition would imply nonlinear tariffs. Finally, all market participants, suppliers and consumers, can in principle benefit from nonlinear tariffs.     

Nonparametric curve estimation with bernstein estimates

In this paper we propose a Bernstein type estimate of the regression functionm(x)=E[Y|X=x]. Various local and global asymptotic properties of this estimate are studied.