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991.
Several multiple comparison procedures (MCPs)were compared for their rates of Type I error and fortheir ability to detect true pairwise differencesamong means when independence of observationsassumption were not satisfied. Monte Carlo resultsshowed that, if independence is not met, none of theprocedures maintain controlled at the chosennominal level, neither using error rate per comparisonor the error rate experimentwise. However, once thedependence of the data was corrected the Type I errorrate was maintained at the same level as when thecorrelation was zero in all the procedures, except forthe Fisher's (1935) least significant differenceprocedure (LSD) and Hayter's (1986) two-stagemodified LSD procedure (FH). At the sametime, conform the correlation increased by a smallamount the power rates also, specially, when the powerwas examined using per-pair power.  相似文献   
992.
993.
Multiple regression analysis with grouped data is often used as a method for exploring environmental preferences, the preferred unit for measurement in such analyses is mean scores rather than individual scores.Although this procedure allows us to reduce the potential for error in measuring different variables and, as a consequence of this, improves the reliability of the technique, it also produces some additional, undesirable effects. The latter include artificial increases in R2 values which give the impression that a high degree of fit has been achieved for the regression model. Indeed, this goodness fit often appears to be better than that which could have been achieved by using individual scores. Further, given that different studies operate with differing numbers of subjects in their groups, the R2 scores which result from the analyses of these groups are not directly comparable.In the following discussion, we demonstrate how any value, other than zero for correlations between variables, can be increased, at will, by simply expanding the number of subjects in each group. We present the specialised formulae used for quantifying this increase and offer a warning about the purely relative nature of any study which bases its conclusions on models of regression analysis using grouped data.  相似文献   
994.
A sharp increase in obesity during the last 15 years in the United States became one of the nation’s main public health problems. The theory of rational addiction seems to explain human behavior in food consumption leading to obesity reasonably well. The interesting thing about our results is that the tax policy, normally used to correct various distortions, is to serve in this case as the preventive policy: additional taxes on future prices of the addictive (sweet) foods contribute to lower sugar consumption and BMI at present time. On the other hand, increasing education level is usually considered a preventive type of policy. In this case, it leads to lowering the levels of the BMI in already overweight and obese population.  相似文献   
995.
Zusammenfassung  YOGA bei Gesundheitsproblemen — Die bewusste Atmung ist ein st?ndiger Begleiter aller Yogahaltungen. Die Atmung erleichtert das Hineingehen in eine Haltung. Komplement?r dazu schafft diese Haltung eine Erweiterung des Atemraums. Das wird am Beispiel der Fischposition deutlich.  相似文献   
996.
Surprise gifts offer more business opportunities than gifts suggested by recipients, because a larger part of the selection and purchase processes can be molded, and such gifts are especially valued by recipients. Yet the extant gift-giving literature explicitly takes into account neither the giver's intention to surprise nor the consequences for the gift selection and purchase processes. The present study investigates surprise gifts from the giver's point of view and disentangles the selection and purchase processes of surprise gifts and gifts that are not meant as surprises. The hypotheses emerge as a consequence of the enhanced pleasure and experiential motivation underlying surprise gifts, as well as their greater inherent perceived risk. According to panel data, design and money-back guarantees are more important for the purchase of surprise gifts (compared with non-surprise gifts), whereas good deals appear less important, and brand name does not seem to matter any more than it does for gifts not intended as a surprise. Also, surprise gifts more often are bought on the spot than non-surprise gifts, without extended information search (similar to impulse purchases), by women alone, and for someone within the household. Finally, the giver usually has a poorer idea of what he or she wants to buy before entering the shop and visits fewer stores to purchase surprise gifts. However, the last three results apply only to appliances which often serve as gifts. These insights lead to significant managerial implications for retailers and manufacturers.  相似文献   
997.
This study investigates the relationship between family control and corporate capital structure considering the dynamic nature of the debt policy and the ownership structure of family firms. Our results show that the sensitivity of debt to fluctuations in cash flow is less pronounced in family firms and highlight that family control increases the speed of adjustment toward target debt. Four dimensions of the family business model explain these results: deviations of voting from cash flow rights, the presence of a second blockholder in the company, involvement of family members in management, and the generation in charge of the business. The weaker negative impact of cash flow on debt is driven by family firms with no control‐enhancing mechanisms, companies with active family participation in management and family businesses that are still controlled by the first generation. By contrast, the more severe agency conflicts between owners and creditors in family firms with a second blockholder lead to more pronounced pecking order behaviour. Furthermore, the higher flexibility in corporate decision‐making of family firms managed by the family and under the influence of the first generation explains why family companies are able to rebalance their capital structure faster.  相似文献   
998.
The paper investigates dynamic linkages between entry and exit rates in Brazilian manufacturing in the context of 231 (four-digit) industries during the 1996–2005 period. The empirical analysis focuses on the estimation of a dynamic panel data model for entry and exit rates, and controls for the business cycle and structural characteristics, such as industrial concentration and suboptimal scale. The empirical evidence is partially consistent with a multiplier effect where synergetic factors prevail by exit inducing exit. Evidence partially supports a competition effect that could be related to a selection process favoring efficiency, as exit induces entry. The business cycle control variable and the aforementioned structural variables appear to play no role in delineating entry and exit linkages. The results are similar, although not identical, to previous evidence for developed countries.  相似文献   
999.
This article quantifies the relationship between market size and innovation in the pharmaceutical industry using improved, and newer, methods and data. We find significant elasticities of innovation to expected market size with a point estimate under our preferred specification of 0.23. This suggests that, on average, $2.5 billion is required in additional revenue to support the invention of one new chemical entity. This magnitude is plausible given recent accounting estimates of the cost of innovation of $800 million to $1 billion per drug, and marginal costs of manufacture and distribution near 50%.  相似文献   
1000.
We investigate the relationship between internationalization and the level of debt financing for more than 18,000 firm/year observations from thirty-one developing countries in the period 1991-2006. We argue that this relationship can be affected by both country-level and firm-level factors. The results show that in developing countries with relatively higher financial development, firm internationalization corresponds with a greater level of debt when firms have more growth opportunities (which also indicate a higher level of asymmetric information). This evidence suggests that relatively developed financial markets in developing countries at least partially mitigate the effect of asymmetric information and decrease the agency cost of debt for firms with higher levels of internationalization.  相似文献   
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