456,241 research outputs found
Elasticity optimism
Estimates of the elasticity of substitution between domestic and foreign varieties are small in macroeconomic data, and substantially larger in disaggregated studies. This may be an artifact of heterogeneity. We use disaggregated multilateral trade data to structurally identify elasticities of substitution in US goods. We spell out a partial equilibrium model to aggregate them adequately at the country level. We compare aggregate elasticities that impose equality across sectors, to estimates allowing for heterogeneity. The former are similar in value to conventional macroeconomic estimates; but they are more than twice larger -up to 7- with heterogeneity. The parameter is central to calibrated models in most of international economics. We discuss the difference our corrected estimate makes in various areas of international economics, including the dynamics of external balances, the international transmission of shocks, international portfolio choice and optimal monetary policy.Trade Elasticities, Aggregation, Calibration, Global Imbalances, International Transmission, International Portfolio, Monetary Policy.
Optimism as a Candidate Health Asset: Exploring Its Links With Adolescent Quality of Life in Sweden
This study aims to understand the role that optimism could play in the context of a health asset approach to promote adolescent health-related quality of life (HRQOL). Adolescents (n = 948), between 11 and 16 years old from a medium-sized rural town in Sweden, answered questionnaires measuring optimism, pessimism, and HRQOL. The findings indicate a significant decrease in optimism and a significant increase in pessimism between early and mid adolescence. The study has allowed us to present associational evidence of the links between optimism and HRQOL. This infers the potential of an optimistic orientation about the future to function as a health asset during adolescence and by implication may provide additional intervention tools in the planning of health promotion strategies.</p
Why the optimism?
In spite of the recent recession, hopes for the New Economy have been little daunted. Surprisingly robust productivity growth during the recent downturn provides compelling new evidence that something truly fundamental is going on. This Commentary argues that advances in information technology, and their diffusion through the economy, justify our optimism. Higher productivity growth is not an ephemeral phenomenon but one likely to persist for some time into the future, perhaps even accelerating further.Economic conditions - United States ; Labor productivity
Optimal choice and beliefs with ex ante savoring and ex post disappointment
We propose a new decision criterion under risk in which people extract both utility from anticipatory feelings ex ante and disutility from disappointment ex post. The decision maker chooses his degree of optimism, given that more optimism raises both the utility of ex ante feelings and the risk of disappointment ex post. We characterize the optimal beliefs and the preferences under risk generated by this mental process and apply this criterion to a simple portfolio choice/insurance problem. We show that these preferences are consistent with the preference reversal in the Allais’ paradoxes and predict that the decision maker takes on less risk compared to an expected utility maximizer. This speaks to the equity premium puzzle and to the preference for low deductibles in insurance contracts. Keywords: endogenous beliefs, anticipatory feeling, disappointment, optimism, decision under risk, portfolio allocation
Consumer optimism and price discrimination
In many principal-agent environments, the two parties hold different prior beliefs
regarding the agent's future preferences. These differences may be due to inherent biases
such as over-optimism or over-pessimism. We analyze the principal's optimal contract
design under the assumption that the agent's prior is private information. In order
to screen the agent's prior, the principal devises a menu of contingent contracts, some
of which are 'speculative' as they involve betting on the agent's future action. We
characterize the optimal menu and show that the characterization enables us to interpret
real-life contract design in a variety of economic contexts
Stock market optimism and participation cost: a mean-variance estimation
We use household data to estimate the cost of participating to financial markets and the cross sectional dispersion of stock market optimism. Our analysis is based on a mean-variance framework, within which we derive structural decision rules for individual composition of the risky assets portfolio to be efficient, as function of both the amount to invest and the optimism about excess return of stocks over bonds. Exploiting the observed heterogeneity in risky asset holdings, we identify both the fixed cost of stock market participation and the dispersion of optimism about excess return. Using the Italian Survey of Household Income and Wealth we estimate a fixed cost of participating to the stock market of about 150 euro per year and a standard deviation of 30% in the optimism about excess returnheterogeneous household portfolios, mean-variance frontier, participation cost, expectation error
How Belief in a Just World Benefits Mental Health: The Effects of Optimism and Gratitude
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Past research suggests that individuals’ belief in a just world (BJW) is closely connected with their mental health. To clarify the underlying mechanism, the current study proposes that BJW encourages optimism and gratitude which then mediates the relation- ship between BJW and mental health as indicated by subjective well-being (SWB) and depression. A sample of 1,200 undergraduates yields results indicating that (a) BJW influences optimism, gratitude, SWB, and depression after controlling for gender, age, income, and personality; (b) optimism and gratitude mediate BJW effects by increasing SWB and decreasing depression. The issues of BJW’s adaptive functions are discussed
Confidence intervals of prediction accuracy measures for multivariable prediction models based on the bootstrap-based optimism correction methods
In assessing prediction accuracy of multivariable prediction models, optimism
corrections are essential for preventing biased results. However, in most
published papers of clinical prediction models, the point estimates of the
prediction accuracy measures are corrected by adequate bootstrap-based
correction methods, but their confidence intervals are not corrected, e.g., the
DeLong's confidence interval is usually used for assessing the C-statistic.
These naive methods do not adjust for the optimism bias and do not account for
statistical variability in the estimation of parameters in the prediction
models. Therefore, their coverage probabilities of the true value of the
prediction accuracy measure can be seriously below the nominal level (e.g.,
95%). In this article, we provide two generic bootstrap methods, namely (1)
location-shifted bootstrap confidence intervals and (2) two-stage bootstrap
confidence intervals, that can be generally applied to the bootstrap-based
optimism correction methods, i.e., the Harrell's bias correction, 0.632, and
0.632+ methods. In addition, they can be widely applied to various methods for
prediction model development involving modern shrinkage methods such as the
ridge and lasso regressions. Through numerical evaluations by simulations, the
proposed confidence intervals showed favourable coverage performances. Besides,
the current standard practices based on the optimism-uncorrected methods showed
serious undercoverage properties. To avoid erroneous results, the
optimism-uncorrected confidence intervals should not be used in practice, and
the adjusted methods are recommended instead. We also developed the R package
predboot for implementing these methods (https://github.com/nomahi/predboot).
The effectiveness of the proposed methods are illustrated via applications to
the GUSTO-I clinical trial
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