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1.
Past research has reported that learning processes in early stage R&D are either chaotic, or absent. We challenge this finding by elaborating Van de Ven et al.’s trial‐and‐error learning model and explore an alternative conceptualization. We explored the combinations of positive and negative outcomes and action course continuation and modification. We use data gathered in an R&D setting of a 4‐years pre‐competitive knowledge generation project in the Dutch paper and board industry. Whereas the Van de Ven and Polley (1992) approach applied on our data also would lead us to conclude that ‘no learning’ would happen, our decomposed model identified three distinct learning patterns: (1) a virtuous pattern of positive outcomes resulting in continuations of action courses; (2) a vacuous pattern of negative outcomes resulting in modifications of action courses; and (3) a verification pattern of positive outcomes resulting in modifications of action courses. We observed the virtuous and verification patterns during the first 2 years and virtuous and vacuous learning in the second 2 years. These results might be useful for R&D managers since they provide insight into how an early stage R&D project can develop and where managers might intervene and adjust action courses.  相似文献   
2.
How does the exposure to product market competition affect the investment horizon of firms? We study if firms have an incentive to shift investments toward more short‐term assets when exposed to tougher competition. Based on a stylized firm investment model, we derive a within‐firm estimator using variation across investments with different durabilities. Exploiting the Chinese World Trade Organization (WTO) accession, we estimate the effects of product market competition on the composition of US firm investments. Firms that experienced tougher competition shifted their expenditures toward investments with a shorter durability. This effect is larger for firms with lower total factor productivity.  相似文献   
3.
Estimation of expected return is required for many financial decisions. For example, an estimate for cost of capital is required for capital budgeting and cost of equity estimates are needed for performance evaluation based on measures such as EVA. Estimates for expected return are often based on the Capital Asset Pricing Model (CAPM), which states that expected excess return (expected return minus the risk-free rate) is equal to the asset's sensitivity to the world market portfolio (β) times the risk premium on the “world market portfolio” (the market risk premium). Since the world market portfolio, by definition, contains all assets in the world, it is not observable. As a result, an estimate for expected return is commonly obtained by taking an estimate for β based on some index (as a proxy for the world market portfolio) and an estimate for the market risk premium based on a potentially different index and multiplying them together. In this paper, it is shown that this results in a biased estimate for expected return. This is undesirable since biased estimates lead to misallocation of funds and biased performance measures. It is also shown in this paper that the straightforward procedure suggested by Fama and MacBeth [J. Financ. Econ. 1 (1974) 43] results in an unbiased estimate for expected return. Further from the analysis done, it follows that, for an unbiased estimate, it does not matter what proxy is used, as long as it is used correctly an unbiased estimate for expected return results.  相似文献   
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This article presents an application of Prezeworski and Teune's so-called “identity-equivalence method” to a large set of indicators of political participation. By relaxing commonly held assumptions about necessary distinctions among types of participation, it is found that the distinction between “conventional” and “unconventional” modes of participation is unnecessary, while the distinction between “government” and “nongovernment” has some merit. The findings also lend further support to the claims of Prezeworski and Teune that the identity-equivalence method is preferable to the identical indicator method.  相似文献   
7.
On Conditional Density Estimation   总被引:1,自引:0,他引:1  
With the aim of mitigating the possible problem of negativity in the estimation of the conditional density function, we introduce a so-called re-weighted Nadaraya-Watson (RNW) estimator. The proposed RNW estimator is constructed by a slight modification of the well-known Nadaraya-Watson smoother. With a detailed asymptotic analysis, we demonstrate that the RNW smoother preserves the superior large-sample bias property of the local linear smoother of the conditional density recently proposed in the literature. As a matter of independent statistical interest, the limit distribution of the RNW estimator is also derived.  相似文献   
8.
I investigate whether a bequest motive for savings influences the post-retirement wealth trajectories of German households. Two measures of the bequest motive are studied: the existence of children as the main group of potential heirs and the respondents' declared intention to bequeath. While having children has no significant impact on households' wealth trajectories, stated bequest intentions are associated with considerable heterogeneity in wealth holdings. The main conclusion from this study is that both the pure life-cycle model and the life-cycle model with bequest motives provide a valid basis for a theory of household wealth accumulation once the heterogeneity of preferences is acknowledged.
JEL classification : D 91; J 14  相似文献   
9.
Generally valid scientific explanations of observable social phenomena are still hardly available. By applying philosophical insights generated by Quine and derived from semiotics to social research methodology three kinds of context dependencies accompanying theory formation within social science are identified. The third context dependency is mostly not attended in theory formation about social phenomena thereby producing a ``connotation fallacy', which leaves almost all social theories undetermined and fallible. These context dependencies should be taken into account in the research design and be tested for using statistical criteria comprising a new methodology presented in this article.  相似文献   
10.
Many observers argue that informed and insider trading is widespread in the emerging financial markets of transition countries, yet rigorous treatment of this issue has been virtually non–existent. The current paper estimates the extent of informed trading on the Prague Stock Exchange (PSE) using intra–day transaction data. Our estimates confirm that the average share of informed trading is equal to 0.32, which is high relative to developed markets and varies considerably among stocks. Using the Easley et al. (1996) approach on the very best segment of the PSE we obtained a high average probability of informed trading. Since data used in this study cover the period after the major attempts to improve market regulations, our results indicate that the PSE needs further strengthening to recover credibility and to become a real source of corporate financing. JEL classification: G14, G15.  相似文献   
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