This thesis consists of four independent essays, which consider different topics in information economics and political economy. The first two papers are variants of the same idea. An uninformed principal, e.g., a government, will make a decision. In order to gain more information it may consult two experts; however, these experts have a private interest in certain policies being implemented. The question is, to gain as much information as possible, should the principal consult experts who are biased in the same direction, or experts who prefer different decisions? The main result is that, as long as collusion between experts can be prevented, homogeneous panels are superior to heterogeneous ones, and this advantage increases with the experts’ informational precision. In the third paper, two firms consider entry in a new product market and must decide when to enter the market and how to design their product. Firms do not know for certain what the best design is, so both firms want to outwait the other’s decision in order to gain more information. The focus of the paper is on which firm will make the first decision. The main result is that if products are strong (strategic) substitutes, the worst informed firm makes the first decision in equilibrium. The analysis should apply to a range of other contexts, such as investors’ trading decisions or the policy choices of political candidates. The final paper asks the following question: Could it be that parties in a two-party system may benefit from using several candidates in the same election? To promote the use of multiple candidates, I assume that a party never runs the risk of having its votes split up among its candidates. Despite this, it turns out that parties have a strong incentive to restrict their number of nominees. Paradoxically, it seems that the more uncertain parties are about voter opinion, the fewer candidates they want to use. In particular, with a uniform voter distribution the optimal number of candidates is one. / Diss. Stockholm : Handelshögsk., 2001 S. v-vii: sammanfattning, s. 1-72: 4 uppsatser

The thesis consists of four papers. The first two essays deal with entry externalities, the third studies the Law of One Price (LOP), while the last essay examines average profits for a monopolist under uncertainty. In the first essay, entry externalities in the form of information and positive payoff externalities are studied. When a firm enters a market, it often imposes externalities on existing firms and/or future potential entrants. If products are substitutes, these externalities are typically negative; if products are complements, the externalities are typically positive. Externalities related to substitution or complementarities between products are called payoff externalities, since entry by one firm has a direct effect on the other firms' payoff. Another type of externality arises when firms have private information about the profitability of entry. In this case, the entry decision of one firm potentially reveals that firm's private information. The focus of the paper is on the scope for intervention for an uninformed social planner, when firms privately know the profitability of entry and moreover, the firms have an option to delay their entry. The main result is that there is insufficient entry, since firms delay too much in equilibrium and further, the social planner can increase welfare by subsidizing early entry. Continuing on this theme, the second essay has the same focus, but instead takes the time of entry as fixed, while generalizing the analysis of payoff externalities also to the case of negative payoff externalities. The main contribution is the characterization of equilibria under both positive and negative payoff externalities and the implications for public policy. Here, the scope for intervention will, in contrast to the results in the first essay, be low, when entry is profitable for uninformed firms. In the third essay (joint with Richard Friberg), deviations from the LOP are studied in the presence of transport costs, under the assumption that firms can endogenously choose to segment markets in order to prevent arbitrage by consumers. It is shown that the deviation from LOP can increase as transport costs fall between countries. The last essay (joint with Richard Friberg), studies the problem facing a monopolist when the cost of inputs is uncertain. The main result is that the monopolist can gain from this uncertainty, in the sense that average profits are increasing in the variability of costs. / Diss. Stockholm : Handelshögsk., 2001