北极冰川融化影响几何？

北极冰川融化将使跨北极通航成为可能，运输公司可减少40％的航运距离。马六甲海峡也将不再垄断国际通运。国际经济将进一步融合。     

Playing for Your Own Audience: Extremism in Two‐Party Elections

This paper considers a two‐party election with a single‐dimensional policy space. We assume that each voter has a higher probability of observing the position of the party he is affiliated with than the position of the other party, an assumption that is consistent with the National Election Studies (NES) electoral data set. In equilibrium, the two parties locate away from the median, because the voters who dislike a party's platform observe its policy choice with a lower probability, and its own audience like policy choices that cater to its taste. As the asymmetry in voter information or the cost of voting increases, the parties adopt more extreme platforms, while if there are fewer extreme voters the opposite effect occurs. Making voters more symmetrically informed about the two parties' platforms increases the welfare of society, while asymmetric information acquisition by the voters is worse than no information acquisition at all.     

Demographic and Economic Pressure on Emigration out of Africa*

Two of the main forces driving European emigration in the late nineteenth century were real wage gaps between sending and receiving regions and demographic booms in the low‐wage sending regions. Our new estimates of net migration for the countries of sub‐Saharan Africa show that exactly the same forces driving African across‐border migration are at work today. The results suggest that rapid growth in the cohort of potential young emigrants, population pressure on the resource base, and slow economic growth are likely to intensify the pressure for migration out of Africa and into high‐wage OECD countries over the next two decades.     

Non‐linear Predictability of UK Stock Market Returns*

Linear predictability of stock market returns has been widely reported. However, recently developed theoretical research has suggested that due to the interaction of noise and arbitrage traders, stock returns are inherently non‐linear, whereby market dynamics differ between small and large returns. This paper examines whether an exponential smooth transition threshold model, which is capable of capturing this non‐linear behaviour, can provide a better characterization of UK stock market returns than either a linear model or an alternate non‐linear model. The results of both in‐sample and out‐of‐sample specification tests support the exponential smooth transition threshold model and hence the belief that investor behaviour does differ between large and small returns.     

Alternative Forms of Mixing Banking with Commerce: Evidence from American History

Much of the discussion about banking and commerce in America has failed to make several crucial distinctions and has not accounted for many arrangements that have promoted the mixing of these activities. We investigate the history of banking and commerce in the United States, looking both at bank control of commercial firms and commercial firms' control of banks. We trace how these controls have changed with shifting definitions of "bank" and changing methods of "control." Despite the regulations prohibiting some arrangements that promote financial control, we find evidence of extensive linkages between banking and commerce in the United States. These linkages usually build on devices that are very close substitutes to the arrangements prohibited by law. Altogether, our findings question the often made claim that traditionally banking in the United States has been separated from commerce. Furthermore, given that research on Japan and Germany has shown that the mixing of banking and commerce matters for a variety of issues, our evidence also raises some questions on similar research in the United States which makes the simplifying assumption that these industries are separated.     

Hiroshima and Nagasaki in Japanese guidebooks

This study investigates the presentations of Hiroshima and Nagasaki as postwar tourism destinations in a selection of Japanese-language guidebooks. Comparison is made between commonly voiced criticisms of Japanese attitudes toward the two atom-bombed sites and the tourism activities suggested by the publications themselves. An expected presentation emphasizing Japanese suffering as a result of the atom bombs is not found in the guides, but neither is an openness to discussion of the war. The conclusions reached find Hiroshima standing as emblematic of the rebuilding nation as a whole, while Nagasaki remains largely outside of the social and cultural dynamics of postwar Japan.     

Interannual Climate Variation, Climate Prediction, and Agricultural Trade: the Costs of Surprise versus Variability

Agriculture remains sensitive to variation in rainfall and temperature. Fortunately, our ability to predict the lower frequency variation in the earth's atmosphere is increasing rapidly. While information cannot affect the underlying source of variability, it allows unexpected shocks to be anticipated and acted upon. This paper develops and analyzes an intertemporal Ricardian trade model with Bayesian beliefs. Results in this paper show that improved climate prediction reduces expected prices, but increases price variability. In addition, trade is crucial to realizing the potential benefits of climate prediction. The value of climate prediction is highest with both storage and trade, and falls by over 300% when a country is in autarky.