Suchergebnisse

Gross stocks of foreign assets have increased rapidly relative to national outputs since 1990, and the short-run capital gains and losses on those assets can amount to significant fractions of GDP. These fluctuations in asset values render the national income and product account measure of the current account balance increasingly inadequate as a summary of the change in a country's net foreign assets. Nonetheless, unusually large current account imbalances, especially deficits, should remain high on policymakers' list of concerns, even for the richer and less credit-constrained countries. Extreme imbalances signal the need for large and perhaps abrupt real exchange rate changes in the future, changes that might have undesired political and financial consequences given the incompleteness of domestic and international asset markets. Furthermore, of the two sources of the change in net foreign assets -- the current account and the capital gain on the net foreign asset position -- the former is better understood and more amenable to policy influence. Systematic government attempts to manipulate international asset values in order to change the net foreign asset position could have a destabilizing effect on market expectations.

External validity captures the extent to which inferences drawn from a given study's sample apply to a broader population or other target populations. Social scientists frequently invoke external validity as an ideal, but they rarely attempt to make rigorous, credible external validity inferences. In recent years, methodologically oriented scholars have advanced a flurry of work on various components of external validity, and this article reviews and systematizes many of those insights. We first clarify the core conceptual dimensions of external validity and introduce a simple formalization that demonstrates why external validity matters so critically. We then organize disparate arguments about how to address external validity by advancing three evaluative criteria: model utility, scope plausibility, and specification credibility. We conclude with a practical aspiration that scholars supplement existing reporting standards to include routine discussion of external validity. It is our hope that these evaluation and reporting standards help rebalance scientific inquiry, such that the current obsession with causal inference is complemented with an equal interest in generalized knowledge.