Wettbewerb in der Restmüllerfassung: Eine empirische Analyse der Anbieterstruktur

Der vorliegende Beitrag ermittelt das aktuelle Ausmaß kommunaler Betätigung in der Abfallwirtschaft auf Basis von 9.248 deutschen Gemeinden und Städten. Vor allem in Großstädten mit über 100.000 Einwohnern haben Kommunen fast vollständig die Restmüllsammlung übernommen. Insgesamt wird über alle Kommunen zwar nur für knapp 34 % der Gebiete die Erfassung durch kommunale Unternehmen vorgenommen. Gewichtet man die jeweiligen Gebiete jedoch mit der Einwohneranzahl, entfällt insgesamt knapp 62 % der Restmüllerfassung auf kommunale Entsorgungsunternehmen. In Großstädten über 100.000 Einwohner haben sich kommunale Unternehmen sogar 94 % des Marktes gesichert. Private Entsorger dominieren hingegen vor allem im ländlichen Raum. Diese Befunde deuten auf eine Rosinenpickerei der Kommunen hin, die sich insbesondere die dicht besiedelten profitablen Gebiete herausgesucht haben. Im Vergleich zu bisher verfügbaren Statistiken über kommunale Aktivitäten in der Abfallwirtschaft (vgl. etwa Monopolkommission, 2014) zeigt sich eine weitere Zunahme der Rekommunalisierung. Sollten die Wettbewerbsbedingungen nunmehr auch in anderen Bereichen der Abfallwirtschaft, wie etwa bei Wertstoffen, zugunsten der Kommunen verzerrt werden, ist hier mit ähnlichen Rekommunalisierungstendenzen und einer Verdrängung privater Wettbewerber zu rechnen

Smoothing time fixed effects

Controlling for time fixed effects in analyses on longitudinal data by means of timedummy variables has long been a standard tool in every applied econometrician's toolbox. In order to obtain unbiased estimates, time fixed effects are typically put forward to control for macroeconomic shocks and are (almost) automatically implemented when longitudinal data are analyzed. The applied econometrician's toolbox contains however no standard method to control for time fixed effects when time-dummy variables are not applicable. A number of empirical applications are crucially concerned with both suffering from bias due to omitting time and time-dummies being inapplicable. This paper introduces a simple and readily available parametric approach to approximate time fixed effects in case time dummy variables are not applicable. Applying Monte Carlo simulations, we show that under certain regulatory conditions, trend polynomials (smoothing time fixed effects) yield consistent estimates by controlling for time fixed effects, also in cases time-dummy variables are inapplicable. As the introduced approach implies testing nested hypotheses, a standard testing procedure enables the identification of the order of the trend polynomial. Applications that may considerably suffer from bias in case time fixed effects are neglected are among others cartel overcharge estimations, merger and regulation analyses and analyses of economic and financial crises. These applications typically divide time into event and control periods, such that standard time dummies may not be applicable due to perfect multicollinearity. In turn, their estimates of interest most crucially need to be purged from other (unobserved) time dependent factors to be consistent as time may by construction induce omitted-variable bias

Total consumer time: A new approach to identifying digital gatekeepers

[Introduction:] The route to customers is becoming increasingly digital, for any business. There is hardly any business that is not focussing on reaching customers online. The Covid-19 pandemic has further accelerated this trend. In many markets, digital platforms have become essential tools for the sale of goods and services. On the one hand, there are transaction platforms for specific goods and services. They are specialist providers in their fields. Consumers access the relevant specialist to directly search for the product or service they intend to purchase, and they expect to directly conclude transactions on the platform ("transaction platforms"). These platforms typically generate the majority of their revenues from sales to consumers or commissions from these sales. On the other hand, there are attention platforms that provide information, entertainment and/or other services (e-mail accounts, translations, search functionality, social media contacts, software use, etc.) to users ("attention platforms"). These platforms are often free of charge for consumers and they generate most of their revenues from advertising. In order to maximize revenues these platforms often aim at maximizing the time that consumers spend within their ecosystems so as to channel consumers' attention to advertising clients or - in case of vertical integration - also to their own offerings. Through the selection of content such as ranking search results and also through advertising these attention platforms can have significant impact on which products receive consumer attention in the first place which enables them to affect and even steer competition. If platforms have such a significant effect on consumer attention that they can steer consumers towards some products and away from others, they may factually become a gatekeeper for these markets. (...