I use daily futures price data to examine the behavior of natural gas and crude oil price volatility in the U.S. since 1990. I test whether there has been a significant trend in volatility, whether there was a short-term increase in volatility during the time of the Enron collapse, and whether natural gas and crude oil price volatilities are interrelated. I also measure the persistence of shock...

This paper analyzes the impact of three termination rules for repeatedgame experiments. We compare treatments with a known finite end, an unknown end and two variants with a random termination rule. The termination rules do not significantly effect cooperation rates. JEL classification numbers: C72, C92, D21, D43

Promoting investments in energy-saving technologies is an important means for achieving environmental goals. Empirical evidence on success conditions of associated policies, however, is scarce. Based on a survey among Dutch firms, this paper sets out to identify the factors that determine the investment behaviour of firms, their attitude towards various types of energy policy, and their respons...

Using plant-level data for the Irish manufacturing sector over the period 1983-98, we study the coagglomeration of domestic plants and foreign multinationals in Ireland. To this end we make use of the index developed by Ellison and Glaeser (1997) and find coagglomeration to be important for a number of sectors. We further test for the impact of coagglomeration on domestic firms’ employment grow...

This paper computes optimal top marginal tax rates in Bewley-Huggett-Aiyagari–type economies that include entrepreneurs. Consistent with the data, entrepreneurs are overrepresented at of income distribution and thus disproportionately affected by an increase rate. The rate maximizes welfare is 60 percent. While average gains positive similar across occupations along transition, they larger for ...

We study how opening to trade affects economic growth in a model where heterogeneous firms can adopt new technologies already use by other their home country. characterize the rate using summary statistic of profit distribution: mean-min ratio. Opening increases spread through increased export opportunities and foreign competition, induces more rapid technology adoption, generates faster growth...

Is firm behavior mainly driven by its environment or rather the characteristics of managers? We develop a cognitive theory manager fixed effects, where allocation managerial attention determines behavior. show that in complex environments, endogenous exacerbates effects. Small differences expertise then may result dramatically different behavior, as managers devote scarce way amplifies initial ...

هدف: از چالش­های عمده بشریت افزایش افسردگی و اختلال عملکرد جنسی ناشی داروهای ضدافسردگی است. با توجه به نقش سلول­های سرتولی در اسپرماتوژنز، پژوهش حاضر، اثر داروی دولوکستین را بر زنده­مانی، آپوپتوزیس بیان ژن­های Bax و­ (Connexin 43) Cx43 بررسی کرده مواد روش‌‌ها: TM4 محیط DMEM/F12 حاوی %5/2 FBS، 5% سرم اسب %1 پنی سیلین-استرپتومایسین کشت شدند. دوزهای 30،60، 15، 5/7، 75/3 میکرو­گرم/ میلی­لیتر زمان­ه...