Regression Sampling in Statistical Auditing: A Practical Survey and Evaluation

Several confidence intervals for the regression estimator are surveyed. A Monte Carlo experiment, based on the NETER and LOEBBECKE (1975) populations, gives estimated coverages and lengths of the different confidence intervals. One interval is exact under the assumption of multivariate normal distributions; it gives longer intervals (hence better coverages) than the interval based on a popular variance estimator. An interval due to ROBERTS (1970) is much too long. Jackknifing gives robust intervals. Rules of thumb for practitioners are given.     

Austrian persistence? Capital-based business cycle theory and the dynamics of investment spending

Survey data are used to investigate the very long spending lags estimated in neoclassical studies of investment expenditures. Neoclassical investment theory has trouble explaining the length of these lags. By recognizing the Austrian concept of the capital structure and applying it to the problem, the present paper explains the length of these lags as proceeding from interactions between types of capital. Austrian arguments stemming from Austrian business-cycle theory seem to be needed to explain these lags. JEL Code E3, E4, C1     

页岩气水平井最优长度研究

页岩气作为一种新兴能源,得到国家与各个能源公司的重视。我国页岩气资源十分丰富,但是我国的页岩气勘探开发刚刚起步。目前广泛采用水平井开发页岩气藏,采用较大的水平段长度可以获得较高的采收率和较大的采油速度,但成本必然相应地增加,采用较小的水平段长度,可以降低成本,但会影响采油速度和最终采收率。由此看来,对于某一具体的水平井,必然存在一个合理水平段长度。本文从采油工程的角度研究页岩气水平井段最优长度的确定方法。     

Minimax after money-max: why major league baseball players do not follow optimal strategies

Using real-life sports data of Major League Baseball, this paper investigates whether professional players follow the minimax theorem in their strategies. Our empirical results using the 2010 regular-season data show that baseball players do not optimize their strategies: there is a significant difference in their payoffs across strategies, and the sequence of their strategy choices is predictable from their previous actions. Further analysis using individual salaries and key contract variables indicates that a higher salary has a positive impact on following minimax strategies in the regular season. By contrast, a longer contract decreases a player’s incentive to pursue optimal strategies in the postseason. These results have important implications for compensation practices in various fields.     

The association between quarter length,forecast errors,and firms’ voluntary disclosures

Approximately 60 percent of adjacent fiscal quarters contain a different number of calendar days. In preliminary analyses, we find the change in quarter length is significantly associated with the changes in sales and earnings and that analysts condition on the prior quarter's results when making their forecasts. These results indicate that it is important for analysts to adjust for changes in quarter length when making forecasts. However, we find the quarterly change in days is positively associated with analysts’ sales and earnings forecasts errors, where forecast error equals the actual earnings minus the forecasted earnings. These results indicate that analysts systematically underestimate (overestimate) performance when quarter length increases (decreases). We find evidence indicating investors make similar errors as returns around earnings announcements are positively associated with the change in quarter length, but only when changes in firm performance is more sensitive to changes in quarter length. Corroborating these findings, managers are more (less) likely to discuss quarter length during conference calls when quarter length decreases (increases). These results are consistent with managers’ strategic disclosure incentives. In summary, our evidence suggests analysts and investors fail to fully take account of the quasi-mechanical effect that quarter length has on firm performance and managers strategically alter their voluntary disclosures to take advantage of these failures.     

测量不确定度在实际工作中的应用

国家校准实验室的认证,计量标准技术报告的建立,检定／校准证书的出具等,都要求检测部门必须提供准确可靠的检测数据,这些检测数据最终还是用测量不确定度来表示。因此,在质量管理和质量保证中,测量不确定度是我们从事计量工作的技术人员必须掌握的理论知识,并以4个实例说明测量不确定度在实际工作中的具体应用。