At Last! An Explicit Solution for the Ramsey Saddle Path

I derive an explicit solution for the saddle path in a Ramsey growth model. The existence of a closed form expression greatly simplifies the analysis of how the parameters of the utility function affects investments and growth.Ramsey growth model

Battlefields and Marketplaces

Divided societies in the developing world experience wasteful struggles for power. We study the relationship between political stability and resources wasted in the struggle within a model of competitive power contests. The model of power contests is similar in structure to models describing oligopolistic market competition. This analogy helps us in deriving results that are new to the conflict literature. We show, for example, that the Herfindahl-Hirschman index can be interpreted as a measure of power concentration and that a peace treaty between fighting groups have a parallel in tacit collusion between firms in a market.Violent conflicts, Rent-seeking games, Herfindahl-Hirschman index, Oligopolistic competition.

King of the Hill Positional Dynamics in Contests

In a contest with positional dynamics between an incumbent and a challenger i) inequality of power may magnify conflicts, ii) more severe conflicts can go together with lower turnover of incumbents, and iii) power can be self defeating as cost advantages can reduce pay-offs. These three propositions of our paper are contrary to the implications of static conflict models. They follow from incorporating positional dynamics into the standard static approach. Such positional dynamics are relevant for competition in battlefields, politics, and market places.Contests;political stability;war;incumbency advantage

With or Without U? - The appropriate test for a U shaped relationship.

Non-linear relationships are common in economic theory, and such relationships are also frequently tested empirically. We argue that the usual test of non-linear relationships is flawed, and derive the appropriate test for a U shaped relationship. Our test gives the exact necessary and sufficient conditions for the test of a U shape in both finite samples and for a large class of models.U shape; hypothesis test; Kuznets curve; Fieller interval

Institutions and the resource curse

Countries rich in natural resources constitute both growth losers and growth winners. We claim that the main reason for these diverging experiences is differences in the quality of institutions. More natural resources push aggregate income down, when institutions are grabber friendly, while more resources raise income, when institutions are producer friendly. We test this theory building on Sachs and Warner's influential works on the resource curse. Our main hypothesis: that institutions are decisive for the resource curse, is confirmed. Our results are in sharp contrast to the claim by Sachs and Warner that institutions do not play a role.Natural resources, Institutional quality, Growth, Rent-seeking

Destructive Creativity

Destructive creativity implies that parasites become more efficient in rent extraction. We focus on destructive creativity in situations where parasites live on rents extracted from the producers. A higher parasitic strength implies that the waste associated with rent seeking increases, and in the long run erodes business productivity, implying that the sustainability of predation is threatened by improved efficiency.

Institutions and the Resource Curse

Countries rich in natural resources constitute both growth losers and growth winners. We claim that the main reason for these diverging experiences is differences in the quality of institutions. More natural resources push aggregate income down, when institutions are grabber friendly, while more resources raise income, when institutions are producer friendly. We test this theory building on Sachs and Warner's influential works on the resource curse. Our main hypothesis: that institutions are decisive for the resource curse, is confirmed. Our results are in sharp contrast to the claim by Sachs and Warner that institutions do not play a role.Natural resources, Institutional quality, Growth, Rent-seeking

Institutions and the resource curse

Countries rich in natural resources constitute both growth losers and growth winners. We claim that the main reason for these diverging experiences is differences in the quality of institutions. More natural resources push aggregate income down, when institutions are grabber friendly, while more resources raise income, when institutions are producer friendly. We test this theory building on Sachs and Warner's influential works on the resource curse. Our main hypothesis: that institutions are decisive for the resource curse, is confirmed. Our results are in sharp contrast to the claim by Sachs and Warner that institutions do not play a role.Natural resources, Institutional quality, Growth, Rent-seeking

Co-variation between climate signals and breeding phenology of high-arctic breeding kittiwakes (Rissa tridactyla)

Climate changes in the Arctic may have important consequences for the breeding of Arctic birds, though few studies are available to evaluate the possible effects. I studied the breeding phenology of kittiwakes (Rissa tridactyla) breeding at two colonies (Krykkjefjellet and Ossian Sarsfjellet) in Kongsfjorden, Svalbard (79°N). Eleven years of data (in the period 1970-2001) from Krykkjefjellet showed no long-term temporal trend in the timing of hatching. The spread of the median hatching date among the years was 14 days. The median hatching date was negatively correlated with the local average April ambient temperature. Correlation analysis with large-scale climate indices showed that the time of hatching was negatively correlated with the Scandinavia index in late winter (February and March), and slightly (but not statistically significantly) negatively correlated with the NAO (North Atlantic Oscillation) winter-index. A similar analysis of the number of breeding kittiwakes in study plots at Ossian Sarsfjellet showed a positive correlation between the number of breeders and average local March temperatures. These observations indicate that the kittiwakes may be able to adjust their spring arrival and breeding phenology to local or large-scale climate variations.key words: climate change, Svalbard, kittiwake, breeding phenology, North Atlantic Oscillatio

Cursed by resources or institutions?

Natural resource abundant countries constitute both growth losers and growth winners, and the main difference between the success cases and the cases of failure lays in the quality of institutions. With grabber friendly institutions more natural resources push aggregate income down, while with producer friendly institutions more natural resources increase income. Such a theory finds strong support in data. A key question we also discuss is if resources in addition alter the quality of institutions. When that is the case, countries with bad institutions suffer a double resource curse - as the deterioration of institutions strenghtens the negative effect of more natural resources.Natural resources; Institutional quality; Growth; Rent-seeking