937 resultados para structural breaks
Resumo:
The purpose of this paper is to examine the degree of persistence in five inflation indicators for Angola, and to identify the implications for decision making. Our results suggest that when structural breaks are accounted for, all five inflation indicators are stationary. Second, our findings suggest that persistence is not too high. Moreover, the degree of persistence is similar among the five inflation indicators and throughout the sample period. Finally, our results also show that extracting the most volatile components of the headline inflation indicator does not generate a new inflation indicator that is less volatile and more persistent than the original. These results have important policy implications as the National Bank of Angola is preparing to change its monetary policy focus to a more inflation-targeting regime
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In this paper, we analyze the behavior of real interest rates over the long-run using historical data for nine developed economies, to assess the extent to which the recent decline observed in most advanced countries is at odds with the past data, as suggested by the Secular Stagnation hypothesis. By using data from 1703 and performing stationarity and structural breaks tests, we find that the recent decline in interest rates is not explained by a structural break in the time series. Our results also show that considering long-run data leads to different conclusions than using short-run data.
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This thesis investigates the pricing effects of idiosyncratic moments. We document that idiosyncratic moments, namely idiosyncratic skewness and idiosyncratic kurtosis vary over time. If a factor/characteristic is priced, it must show minimum variation to be correlated with stock returns. Moreover, we can identify two structural breaks in the time series of idiosyncratic kurtosis. Using a sample of US stocks traded on NYSE, AMEX and NASDAQ markets from January 1970 to December 2013, we run Fama-MacBeth test at the individual stock level. We document a negative and significant pricing effect of idiosyncratic skewness, consistent with the finding of Boyer et al. (2010). We also report that neither idiosyncratic volatility nor idiosyncratic kurtosis are consistently priced. We run robustness tests using different model specifications and period sub-samples. Our results are robust to the different factors and characteristics usually included in the Fama-MacBeth pricing tests. We also split first our sample using endogenously determined structural breaks. Second, we divide our sample into three equal sub-periods. The results are consistent with our main findings suggesting that expected returns of individual stocks are explained by idiosyncratic skewness. Both idiosyncratic volatility and idiosyncratic kurtosis are irrelevant to asset prices at the individual stock level. As an alternative method, we run Fama-MacBeth tests at the portfolio level. We find that idiosyncratic skewness is not significantly related to returns on idiosyncratic skewness-sorted portfolios. However, it is significant when tested against idiosyncratic kurtosis sorted portfolios.
Resumo:
This thesis investigates the pricing effects of idiosyncratic moments. We document that idiosyncratic moments, namely idiosyncratic skewness and idiosyncratic kurtosis vary over time. If a factor/characteristic is priced, it must show minimum variation to be correlated with stock returns. Moreover, we can identify two structural breaks in the time series of idiosyncratic kurtosis. Using a sample of US stocks traded on NYSE, AMEX and NASDAQ markets from January 1970 to December 2013, we run Fama-MacBeth test at the individual stock level. We document a negative and significant pricing effect of idiosyncratic skewness, consistent with the finding of Boyer et al. (2010). We also report that neither idiosyncratic volatility nor idiosyncratic kurtosis are consistently priced. We run robustness tests using different model specifications and period sub-samples. Our results are robust to the different factors and characteristics usually included in the Fama-MacBeth pricing tests. We also split first our sample using endogenously determined structural breaks. Second, we divide our sample into three equal sub-periods. The results are consistent with our main findings suggesting that expected returns of individual stocks are explained by idiosyncratic skewness. Both idiosyncratic volatility and idiosyncratic kurtosis are irrelevant to asset prices at the individual stock level. As an alternative method, we run Fama-MacBeth tests at the portfolio level. We find that idiosyncratic skewness is not significantly related to returns on idiosyncratic skewness-sorted portfolios. However, it is significant when tested against idiosyncratic kurtosis sorted portfolios.
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Cette thèse est composée de trois articles en économie des ressources naturelles non-renouvelables. Nous considérons tour à tour les questions suivantes : le prix in-situ des ressources naturelles non-renouvelables ; le taux d’extraction optimal et le prix des res- sources non-renouvelables et durables. Dans le premier article, nous estimons le prix in-situ des ressources naturelles non-renouvelables en utilisant les données sur le coût moyen d’extraction pour obtenir une approximation du coût marginal. En utilisant la Méthode des Moments Généralisés, une dynamique du prix de marché derivée des conditions d’optimalité du modèle d’Hotelling est estimée avec des données de panel de 14 ressources naturelles non-renouvelables. Nous trouvons des résultats qui tendent à soutenir le modèle. Premièrement, le modèle d’Hotelling exhibe un bon pouvoir explicatif du prix de marché observé. Deuxièmement, bien que le prix estimé présente un changement structurel dans le temps, ceci semble n’avoir aucun impact significatif sur le pouvoir explicatif du modèle. Troisièmement, on ne peut pas rejeter l’hypothèse que le coût marginal d’extraction puisse être approximé par les données sur le coût moyen. Quatrièmement, le prix in-situ estimé en prenant en compte les changements structurels décroît ou exhibe une forme en U inversé dans le temps et semble être corrélé positivement avec le prix de marché. Cinquièmement, pour neuf des quatorze ressources, la différence entre le prix in-situ estimé avec changements structurels et celui estimé en négligeant les changements structurels est un processus de moyenne nulle. Dans le deuxième article, nous testons l’existence d’un équilibre dans lequel le taux d’extraction optimal des ressources non-renouvelables est linéaire par rapport au stock de ressource en terre. Tout d’abord, nous considérons un modèle d’Hotelling avec une fonction de demande variant dans le temps caractérisée par une élasticité prix constante et une fonction de coût d’extraction variant dans le temps caractérisée par des élasticités constantes par rapport au taux d’extraction et au stock de ressource. Ensuite, nous mon- trons qu’il existe un équilibre dans lequel le taux d’extraction optimal est proportionnel au stock de ressource si et seulement si le taux d’actualisation et les paramètres des fonctions de demande et de coût d’extraction satisfont une relation bien précise. Enfin, nous utilisons les données de panel de quatorze ressources non-renouvelables pour vérifier empiriquement cette relation. Dans le cas où les paramètres du modèle sont supposés invariants dans le temps, nous trouvons qu’on ne peut rejeter la relation que pour six des quatorze ressources. Cependant, ce résultat change lorsque nous prenons en compte le changement structurel dans le temps des prix des ressources. En fait, dans ce cas nous trouvons que la relation est rejetée pour toutes les quatorze ressources. Dans le troisième article, nous étudions l’évolution du prix d’une ressource naturelle non-renouvelable dans le cas où cette ressource est durable, c’est-à-dire qu’une fois extraite elle devient un actif productif détenu hors terre. On emprunte à la théorie de la détermination du prix des actifs pour ce faire. Le choix de portefeuille porte alors sur les actifs suivant : un stock de ressource non-renouvelable détenu en terre, qui ne procure aucun service productif ; un stock de ressource détenu hors terre, qui procure un flux de services productifs ; un stock d’un bien composite, qui peut être détenu soit sous forme de capital productif, soit sous forme d’une obligation dont le rendement est donné. Les productivités du secteur de production du bien composite et du secteur de l’extraction de la ressource évoluent de façon stochastique. On montre que la prédiction que l’on peut tirer quant au sentier de prix de la ressource diffère considérablement de celle qui découle de la règle d’Hotelling élémentaire et qu’aucune prédiction non ambiguë quant au comportement du sentier de prix ne peut être obtenue de façon analytique.
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Este documento examina la hipótesis de sostenibilidad fiscal para 8 países de Latinoamérica. A partir de un modelo de datos panel, se determina si los ingresos y gasto primario de los Gobiernos entre 1960 - 2009 están cointegrados, es decir, si son sostenibles a largo plazo. Para esto, se utilizaron pruebas de raíz unitaria y cointegración de segunda generación con datos panel macroeconómicos, lo que permite tener en cuenta la dependencia cruzada entre los países, así como los posibles quiebres estructurales en la relación que estén determinados de manera endógena; en particular, se usan la prueba de estacionariedad de Hadri y Rao (2008) y la prueba de cointegración de Westerlund (2006). Como resultado del análisis se encontró evidencia empírica de que en el período bajo estudio el déficit primario en los 8 países latinoamericanos es sostenible pero en sentido débil.
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In this paper, we examine the temporal stability of the evidence for two commodity futures pricing theories. We investigate whether the forecast power of commodity futures can be attributed to the extent to which they exhibit seasonality and we also consider whether there are time varying parameters or structural breaks in these pricing relationships. Compared to previous studies, we find stronger evidence of seasonality in the basis, which supports the theory of storage. The power of the basis to forecast subsequent price changes is also strengthened, while results on the presence of a risk premium are inconclusive. In addition, we show that the forecasting power of commodity futures cannot be attributed to the extent to which they exhibit seasonality. We find that in most cases where structural breaks occur, only changes in the intercepts and not the slopes are detected, illustrating that the forecast power of the basis is stable over different economic environments.
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This chapter applies rigorous statistical analysis to existing datasets of medieval exchange rates quoted in merchants’ letters sent from Barcelona, Bruges and Venice between 1380 and 1310, which survive in the archive of Francesco di Marco Datini of Prato. First, it tests the exchange rates for stationarity. Second, it uses regression analysis to examine the seasonality of exchange rates at the three financial centres and compares them against contemporary descriptions by the merchant Giovanni di Antonio da Uzzano. Third, it tests for structural breaks in the exchange rate series.
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Using cluster analysis this study reveals significant heterogeneity in the institutional characteristics of European mortgage markets. Distinct clusters are formed which can be related to differences in the mortgage credit system, the relative importance of the owner-occupation and the property specific fiscal system. The paper then tests for multiple structural breaks. We find evidence that structural breaks in European housing markets often coincide with a changes in housing market policy.
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Existing theoretical models of house prices and credit rely on continuous rationality of consumers, an assumption that has been frequently questioned in recent years. Meanwhile, empirical investigations of the relationship between prices and credit are often based on national-level data, which is then tested for structural breaks and asymmetric responses, usually with subsamples. Earlier author argues that local markets are structurally different from one another and so the coefficients of any estimated housing market model should vary from region to region. We investigate differences in the price–credit relationship for 12 regions of the UK. Markov-switching is introduced to capture asymmetric market behaviours and turning points. Results show that credit abundance had a large impact on house prices in Greater London and nearby regions alongside a strong positive feedback effect from past house price movements. This impact is even larger in Greater London and the South East of England when house prices are falling, which are the only instances where the credit effect is more prominent than the positive feedback effect. A strong positive feedback effect from past lending activity is also present in the loan dynamics. Furthermore, bubble probabilities extracted using a discrete Kalman filter neatly capture market turning points.
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This paper examines structural changes that occur in the total factor productivity (TFP) within countries. It is possible that some episodes of high economic growth or economic decline are associated with permanent productivity shocks, therefore, this research has two objectives. The Örst one is to estimate the structural changes present in TFP for a sample of 81 countries between 1950(60) and 2000. The second one is to identify, whenever possible, episodes in the political and economic history of these countries that may account for the structural breaks in question. The results suggest that about 85% of the TFP time-series present at least one structural break, moreover, at least half the structural changes can be attributed to internal factors, such as independence or a newly adopted constitution, and about 30% to external shocks, such as oil shock or shocks in international interest rates. The majority of the estimated breaks are downwards, indicating that after a break the TFP tends to decrease, implying that institutional rearrangements, external shocks, or internal shocks may be costly and from which it is very di¢ cult to recover.
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The article suggests a new test for strong hysteresis in international trade. The variables that capture the effects of hysteresis are based on the model of Dixit (1989) with calibrations using a state-space model to determine the parameters for each point in time. These variables are then applied to a cointegration test with breaks, where it is possible to verify whether the hysteresis effect is essential in determining the long-term equilibrium.
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The purpose of this paper is to test the hypothesis of long-run purchasing power parity (PPP) for all Latin American countries. These countries share similar economic history and contagious effects from currency crises, which might lead to comovements in their real exchange rates. New time series unit root tests found evidence of PPP for the vast majority of countries. In the panel data framework, tests for the null of unit root, null of stationarity, and unit root under multiple structural breaks indicated stationary real exchange rates. Thus, there is convincing evidence that PPP holds for Latin-American countries in the post-1980 period.
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O setor automotivo é bastante representativo na economia nacional, o que motivou a realização deste estudo sobre a demanda por veículos novos no Brasil. No presente trabalho, é abordado um modelo econométrico que permite calcular as elasticidades do preço, da renda e do crédito em relação à demanda por veículos, sob a luz da teoria da cointegração. Analisando-se o período de junho de 2000 a janeiro de 2014, verifica-se a ocorrência de três quebras estruturais. Estas quebras dividem o intervalo de tempo analisado em quatro subperíodos, cada um com uma dinâmica própria. A constatação deste fato, muitas vezes negligenciado na literatura científica prévia, é um dos principais resultados deste trabalho: afinal, conclusões bastante distintas seriam obtidas ao se considerar o período todo sem quebras. Vale também destacar que o crédito se mostrou relevante para a demanda em todos os subperíodos: acredita-se, portanto, ser efetiva a implementação de uma política de estímulo ao setor, por meio do incentivo ao crédito. Por último, comenta-se que, no passado recente, a cada 1% de redução no preço do automóvel, a demanda aumentou numa proporção 30% maior. Este resultado corrobora com a percepção de que a redução de impostos pode alavancar a venda de veículos.