Reliable Broadcasting and Streaming of Multimedia Content

This thesis is focused on the study of techniques that allow to have reliable transmission of multimedia content in streaming and broadcasting applications, targeting in particular video content. The design of efficient error-control mechanisms, to enhance video transmission systems reliability, has been addressed considering cross-layer and multi-layer/multi-dimensional channel coding techniques to cope with bit errors as well as packet erasures. Mechanisms for unequal time interleaving have been designed as a viable solution to reduce the impact of errors and erasures by acting on the time diversity of the data flow, thus enhancing robustness against correlated channel impairments. In order to account for the nature of the factors which affect the physical layer channel in the evaluation of FEC schemes performances, an ad-hoc error-event modeling has been devised. In addition, the impact of error correction/protection techniques on the quality perceived by the consumers of video services applications and techniques for objective/subjective quality evaluation have been studied. The applicability and value of the proposed techniques have been tested by considering practical constraints and requirements of real system implementations.

Essays in Media and Finance

This Ph.D. thesis consists in three research papers focused on the relationship between media industry and the financial sector. The importance of a correct understanding what is the effect of media on financial markets is becoming increasingly important as long as fully informed markets hypothesis has been challenged. Therefore, if financial markets do not have access to complete information, the importance of information professionals, the media, follows. On the other side, another challenge for economic and finance scholar is to understand how financial features are able to influence media and to condition information disclosure. The main aim of this Ph.D. dissertation is to contribute to a better comprehension for both the phenomena. The first paper analyzes the effects of owning equity shares in a newspaper- publishing firm. The main findings show how for a firm being part of the ownership structure of a media firm ends to receive more and better coverage. This confirms the view in which owning a media outlet is a source of conflicts of interest. The second paper focuses on the effect of media-delivered information on financial markets. In the framework of IPO in the U.S. market, we found empirical evidence of a significant effect of the media role in the IPO pricing. Specifically, increasing the quantity and the quality of the coverage increases the first-day returns (i.e. the underpricing). Finally the third paper tries to summarize what has been done in studying the relationship between media and financial industries, putting together contributes from economic, business, and financial scholars. The main finding of this dissertation is therefore to have underlined the importance and the effectiveness of the relationship between media industry and the financial sector, contributing to the stream of research that investigates about the media role and media effectiveness in the financial and business sectors.