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51.
Gail D.Fosler 《国际经济评论》2008,(1):9-10
一、全球经济展望 实际上要想做得精确非常容易,但是要想做正确是很难的,经济学家在社会当中只会"正确"两字,所以我想给大家介绍各种各样的想法,并进行讨论,你们可以自己判断经济的前景到底如何,以及我们面临怎样的风险. 相似文献
52.
The main purpose of this study was to evaluate the performance of the electrochemical oxidation process as a post-treatment for the effluents of a bench-scale UASB reactor treating simulated wastewater from an unbleached pulp plant. The oxidation process was performed using a single compartment cell with two plates as electrodes. The anode was made of Ti/Ru0.3Ti0.7O2 and the cathode of stainless steel. The following variables were evaluated: current density (75, 150 and 225 mA cm(-2)) and recirculation flow rate in the electrochemical cell (0.22, 0.45 and 0.90 L h(-1)). The increase in current density from 75 to 225 mA cm(-2) did not increased the color removal efficiency for the tested flow rates, 0.22, 0.45 and 0.90 L h(-1), however the energy consumption increased significantly. The results indicated the technical feasibility of the electrochemical treatment as post-treatment for UASB reactors treating wastewaters from pulp and paper plants. 相似文献
53.
Using a measure of default likelihood based on an option pricing method, we provide evidence that Fed policy actions affect the financial distress of commercial banks. When the Fed increases (decreases) interest rates, the measure of default likelihood increases (decreases). We show that when the Fed uses a tight money policy, the increase in default likelihood is more pronounced for banks that have less capital, have greater financial leverage, are smaller, have fewer growth opportunities, and have lower asset quality. Additionally, the effects on bank default likelihood are more pronounced when the Fed's policy signals less concern about economic growth, as indicated by its bias toward further tightening, and when there is a market expectation of higher short‐term market rates in the future. 相似文献
54.
K.A. Al-Abdulqader G. Hannah D.M. Power 《Research in International Business and Finance》2007,21(1):69-86
This paper reports on a questionnaire survey about share valuation practices among investors and their intermediaries in Saudi Arabia. The findings suggest that fundamental analysis is used most by investor respondents where a P/E multiple is applied to an earnings forecast to generate a prediction of future price. However, technical analysis is also used to a much greater extent than in developed markets. Finally, the results indicate that quarterly and annual reports as well as newspapers are widely consulted by investors when forming their expectations about share valuations. 相似文献
55.
The biological decolorization of two industrial, spent textile reactive dyebaths was investigated using a suspended-growth, halophilic mixed culture fed with glucose. Dyebath I contained mainly Reactive Blue 19 (RB19), an anthraquinone dye, whereas dyebath II contained mainly Reactive Blue 21 (RB21), a phthalocyanine dye. Batch assays under anaerobic conditions with the two neutralized dyebaths resulted in 87 and 37% extent of decolorization for dyebaths I and II, respectively. The rate of glucose utilization and the extent of acetate production were impacted in the presence of each dyebath as compared to the control culture. However, dyebath decolorization occurred despite moderate culture inhibition. Reuse of a biologically renovated RB19-containing dyebath in the dyeing process resulted in reproducible but not identical cotton fabric shades as compared to a standard dyeing (i.e., control) using fresh water. This difference is attributed to a variable degree of RB19 aggregation during the dyeing process and is not related to the efficiency of the biodecolorization process. Further improvement of the redyeing efficiency will lead to the development of an in-plant, closed-loop decolorization system resulting in significant water conservation and minimization of textile pollutants such as salt and dyes. 相似文献
56.
This paper examines the welfare implications of alternative inflation targeting proposals for the monetary policy of the European Central Bank. We assume that policy makers have to “learn” the laws of motion of inflation in an economy characterized by “stickiness” in domestic price setting behavior and subjected to recurring shocks to productivity, exports and foreign price. We find that a switch from an “asymmetric” inflation targeting strategy to an “symmetric” makes little difference in welfare payoffs, but it comes at a cost of much higher interest-rate variability. We also find that there are practically no welfare gains from switching from an inflation-targeting strategy based on the Harmonized Index of Consumer Prices (HICP) to a strategy based on the domestic price component of the HICP. 相似文献
57.
Alan D. Morrison 《Journal of Business Finance & Accounting》2004,31(7-8):1171-1190
Abstract: The microstructure literature models the mechanisms through which fundamental information is incorporated into market prices. This paper extends previous models by endogenising information production and analysing incentives for costly information production. In contrast to the existing literature, increasing the number of informed traders can result in reduced price informativeness. When prices have an allocative role this has welfare consequences: the regulatory implications of a dichotomy between private and public incentives for information gathering are discussed. 相似文献
58.
Comparison of nutrient cycling in a surface-flow constructed wetland and in a facultative pond treating secondary effluent. 总被引:1,自引:0,他引:1
There is a growing interest in the possibilities offered by combinations of waste stabilisation ponds (WSP) and constructed wetlands (CW). The purpose of our study was to compare treatment performances and nutrient cycling in a surface-flow wetland (SFW) and in a WSP treating secondary effluent. In the period between 2000 and 2003, a pilot SFW and a pilot WSP were constructed at the outlet of the wastewater treatment plant and their performance monitored while both were active under the same conditions. The SFW was planted with Phragmites australis and Eichhornia crassipes, while in the WSP development of algae was spontaneous. Performance efficiency was monitored by means of evaluation of physical and chemical parameters in water, by measurement of plant productivity and by analysis of N and P contents in biomass. The SFW with macrophytes proved more efficient in decreasing the suspended solids (64.6%), settleable solids (91.8%), organic N (59.3%), total N (38%), COD (67.2%) and BOD5 (72.1%) than the WSP. The WSP with algae was more efficient in treatment of ammonia nitrogen (48.9%) and ortho-phosphate (43.9%). The results of this study provide data that are of help in optimising combinations of SFW and WSP. 相似文献
59.
Abstract. This research re-examines whether there are differences in the forecast accuracy of financial analysts through a comparison of their annual earnings per share forecasts. The comparison of analyst forecast accuracy is made on both an ex post (within sample) and an ex ante (out of sample) basis. Early examinations of this issue by Richards (1976), Brown and Rozeff (1980), O'Brien (1987), Coggin and Hunter (1989), O'Brien (1990), and Butler and Lang (1991) were ex post and suggest the absence of analysts who can provide relatively more accurate forecasts over multiple years. Contrary to the results of prior research and consistent with the belief in the popular press, we document that differences do exist in financial analysts' ex post forecast accuracy. We show that the previous studies failed to find differences in forecast accuracy due to inadequate (or no) control for differences in the recency of forecasts issued by the analysts. It has been well documented in the literature that forecast recency is positively related to forecast accuracy (Crichfield, Dyckman, and Lakonishok 1978; O'Brien 1988; Brown 1991). Thus, failure to control for forecast recency may reduce the power of tests, making it difficult to reject the null hypothesis of no differences in forecast accuracy even if they do exist. In our analysis, we control for the differences in recency of analysts' forecasts using two different approaches. First, we use an estimated generalized least squares estimation procedure that captures the recency-induced effects in the residuals of the model. Second, we use a matched-pair design whereby we measure the relative forecast accuracy of an analyst by comparing his/her forecast error to the forecast error of another randomly selected analyst making forecasts for the same firm in the same year on or around the same date. Using both approaches, we find that differential forecast accuracy does exist amongst analysts, especially in samples with minimum forecast horizons of five and 60 trading days. We show that these differences are not attributable to differences in the forecast issuance frequency of the financial analysts. In sum, after controlling for firm, year, forecast recency, and forecast issuance frequency of individual analysts, the analyst effect persists. To validate our findings, we examine whether the differences in the forecast accuracy of financial analysts persist in holdout periods. Analysts were assigned a “superior” (“inferior”) status for a firm-year in the estimation sample using percentile rankings on the distribution of absolute forecast errors for that firm-year. We use estimation samples of one- to four-year duration, and consider two different definitions of analyst forecast superiority. Analysts were classified as firm-specific “superior” if they maintained a “superior” status in every year of the estimation sample. Furthermore, they were classified as industry-specific “superior” if they were deemed firm-specific “superior” with respect to at least two firms and firm-specific “inferior” with respect to no firm in that industry. Using either definition, we find that analysts classified as “superior” in estimation samples generally remain superior in holdout periods. In contrast, we find that analysts identified as “inferior” in estimation samples do not remain inferior in holdout periods. Our results suggest that some analysts' earnings forecasts should be weighted higher than others when formulating composite earnings expectations. This suggestion is predicated on the assumption that capital markets distinguish between analysts who are ex ante superior, and that they utilize this information when formulating stock prices. Our study provides an ex ante framework for identifying those analysts who appear to be superior. When constructing weighted forecasts, a one-year estimation period should be used because we obtain the strongest results of persistence in this case. 相似文献
60.