Michal Grajek

Usage and Diffusion of Cellular Telephony, 1998-2004

We study the dynamics of usage intensity of second-generation cellular telephony over the diffusion curve. Specifically, we address two questions: First, can we draw conclusions about the underlying drivers of technology diffusion by studying usage intensity? Second, what is the effect of high penetration of previous generations and competing networks on network usage intensity? Using an operator-level panel covering 41 countries with quarterly data over 6 years, we find that heterogeneity among adopters dominates network effects and that different technological generations are complements in terms of usage, but substitutes in terms of subscription.

Estimating network effects and compatibility: Evidence from the Polish mobile market

I develop a structural demand model for mobile telephony that facilitates the identification of network effects and inter-network compatibility. Network effects are measured as the dependence of consumer willingness to pay on the installed base of subscribers, compatibility as the relative extent of cross- and own-network effects. Estimating the model using quarterly panel data from the Polish mobile telephone market for the period 1996-2001, I find strong network effects and, despite full interconnection of the mobile telephone networks, low compatibility. I also show that ignoring network effects leads to overestimation of demand elasticity.

Estimating Network Effects and Compatibility in Mobile Telecommunications

This paper provides empirical evidence on the extent of network effects and compatibility between networks in mobile telecommunications. We specify a structural model of demand for mobile telephone service, which allows us to identify the parameters of interest from the S-shape of mobile service diffusion. The network effects are measured by the dependence of consumer willingness to pay on the installed base of subscribers. Compatibility is measured by the relative extent of cross- and own-network effects. As such, it indicates whether the network effects operate at the firm level, at the industry level, or at both. We then estimate this model for the Polish mobile telephone industry using quarterly panel data for the period 1996-2001. We find strong network effects, which give rise to upward-sloping demand, and, despite full interconnection of the mobile telephone networks, low compatibility. We show also that ignoring network effects in empirical models of emerging network industries might substantially bias downward the estimated price elasticity of demand. ZUSAMMENFASSUNG - (Schatzung von Netzwerkeffekten und Kompatibilitat in Mobilfunktelekommunikation) Der vorliegende Beitrag bietet empirische Evidenz fur den Umfang von Netzwerkeffekten und Netzwerkkompatibilitat in der Mobilfunktelekom-munikation. Wir spezifizieren ein strukturelles Modell fur die Nachfrage von Mobilfunkdienstleistungen, das die Parameter von Interesse mithilfe der S-formigen Funktion der Dienstleistungsdiffusion identifiziert. Die Netzwerkeffekte werden durch die Abhangigkeit der Zahlungsbereitschaft der Konsumenten von der installierten Abonnentenbasis gemessen. Netzwerkkompatibilitat wird durch den relativen Umfang der Quer- und Eigen-Netzwerkeffekte gemessen. Sie weist darauf hin, ob Netzwerkeffekten auf Unternehmensebene, auf Industrieebene, oder auf beiden Ebenen bestehen. Dann schatzen wir das Modell fur die Polnische Mobilfunkindustrie mit vierteljahrlichen Paneldaten fur 1996-2001. Wir stellen starke Netzwerkeffekte fest, die eine positive Steigung in der Nachfragefunktion verursachen, und - trotz der technisch vollstandigen Querverbindung der Mobilfunknetze - niedrige Kompatibilitat. Wir zeigen auch, dass das Ubersehen von Netzwerkeffekten in empirischen Modellen von neuen Netzwerkindustrien die geschatzte Preiselastizitat der Nachfrage signifikant nach unten verzerren kann.

Estimating Critical Mass in the Global Cellular Telephony Market

Critical Mass is a common feature of technology diffusion processes. We develop a structural model of demand with network effects to provide a rigorous definition of critical mass as a function of installed base, price and network effects. Using data from the digital cellular telephony market, we identify critical mass phenomena and find that differences in the critical mass point in different countries rest mainly on different countries’ socioeconomic characteristics and the extent of competition in a country. This application illustrates that our demand model can be operationalized easily and can generate theoretically grounded empirical insights about critical mass phenomena.

Estimating Level Effects in Diffusion of a New Technology: Barcode Scanning at the Checkout Counter

Cross-country or cross-industry studies of technology diffusion typically estimate how independent factors affect diffusion speed or timing, often based on a two-stage approach. In many applications, however, countries (industries) differ most in the saturation level of diffusion. In a single-stage econometric approach to a standard diffusion model, we therefore estimate how the saturation level covaries with independent factors. In our application to diffusion of an important retail information technology, we focus on the competitive effect of hypermarkets (superstores). We also find standard scale, income and labour substitution effects.

ISO 9000: New Form of Protectionism or Common Language in International Trade?

International standards have the potential to both promote and hinder international trade. Yet empirical scholarship on the standards-trade relationship has been held up due to some methodological challenges: measurement problems, varied effects, and endogeneity concerns. We are able to surmount these challenges while considering the impact of one particular standard on the country-pair trade flows between 91 nations over the 1995-2005 period. To deal with these challenges, we measure the degree of standardization via the penetration of ISO 9000 in individual nations, allow ISO diffusion to manifest via multiple (quality-signaling, information/compliance-cost, and common-language) effects, and use instrumental variable and panel data techniques to overcome endogeneity concerns. We find strong evidence in support of ISO 9000 involving a common-language effect that enhances country-pair trade; yet, the evidence is more mixed with regard to the quality-signaling and information/compliance-cost effects. While we find ISO-rich nations (most notably European) to clearly benefit from the worldwide diffusion of standardization, ISO 9000 represents a de facto trade barrier for nations (e.g., the US and Mexico) lagging behind in terms of adoption.

Hypermarket Competition and the Diffusion of Retail Checkout Barcode Scanning

This paper presents a set of panel data to study the diffusion of retail checkout barcode scanning in ten European countries over the period 1981-1996. Estimates from a standard diffusion model suggest that countries differ most in the long-run diffusion level of barcode scanning and less in timing or diffusion speed. We present evidence that the emergence of hypermarkets raises competitive intensity and use hypermarket data, among other variables, in a pooled estimation. Results suggest that hypermarket competition reduces long-run adoption of information technology (IT) in retailing. In particular, the emergence of hypermarkets seems to deepen retail segmentation by inducing potential adopters (e.g. supermarkets) to exit the market and/or by discouraging adoption by other retail formats. Consistent with expectations, scale and income effects spur IT diffusion and there is a classic substitution effect: when wages rise, diffusion of a labor-saving technology such as barcode scanning is more intense. We do not find a significant impact of employment protection legislation.

Performance implications of core and complementary pre-entry experience: The role of consumer heterogeneity in mobile telephony

We study how two distinct types of pre-entry experience – core technological experience and market-based complementary experience – affect post-entry performance in a new industry. We focus on the fit between capabilities generated through pre-entry experience and the preferences of heterogeneous consumer segments. Specifically, we suggest that firms with pre-entry experience in the focal technology will attract more valuable consumers, but as these consumers typically make adoption decisions early the firm must enter early to benefit. Conversely, firms with pre-entry experience in the focal market will attract a larger share of less valuable consumers regardless of entry timing. Our empirical analysis of the global 2G mobile telecommunications industry supports our theory and provides important insights for research on experience and entry dynamics in high-technology industries.

Speeding Up the Internet: Regulation and Investment in European Fiber Optic Infrastructure

In this paper we study how the coexistence of access regulations for legacy (copper) and fiber networks shapes the incentives to invest in network infrastructure. To this end, we develop a theoretical model explaining investment incentives by incumbent telecom operators and heterogeneous entrants and test its main predictions using panel data from 27 EU member states over the last decade. Our theoretical model extends the existing literature by, among other things, allowing for heterogeneous entrants in internet access markets, as we consider both other telecom and cable TV operators as entrants. In the empirical part, we use a novel data set including information on physical fiber network investments, legacy network access regulation and recently imposed fiber access regulations. Our main finding is that more stringent access regulations for both the legacy and the fiber networks harm investments by incumbent telecom operators, but, in line with our theoretical model, do not affect cable TV operators.

Static or dynamic efficiency: Horizontal merger effects in the wireless telecommunications industry

This paper studies five mergers in the European wireless telecommunication industry and analyzes their impact on prices and capital expenditures of both merging carriers and their rivals. We find substantial heterogeneity in the relationship between increases in concentration and carriers’ prices. The specifics of each merger case clearly matter. Moreover, we find a positive correlation between the price and the investment effects; when the prices after merger increase (decrease), the investments increase (decrease) too. Thus, we document a trade-off between static and dynamic efficiencies of mergers.