We consider the asymptotic distribution of the normalized periodogram ordinates Z(o+)/f(w,) ( j = 1,2, . . .) of a general long-memory time series. Here, I(. )is the periodogram based on a sample size n, f( .) is the spectral density and 0, = 27rj/n. We assume that n -+ m with j held fixed, and so our focus is on low frequencies; these are the most important frequencies for the periodogram-based estimation of the memory parameter d . Contrary to popular belief, the normalized periodogram ordinates obtained from a Gaussian process are asymptotically neither independent identically distributed nor exponentially distributed. In fact, limn E { I(oJ/)/ f ( w , ) } depends on both j and d and is typically greater than unity, implying a positive asymptotic relative bias in I(w,) as an estimator of f ( w , ) . Tapering is found to reduce this bias dramatically, except at frequency wi. The asymptotic distribution of I ( w~) / f ( w / ) for a Gaussian process is, in general, that of an unequally weighted linear combination of two independent x: random variables. The asymptotic mean of the log normalized periodogram depends on j and d and is not in general equal to the negative of Euler's constant, as is commonly assumed. Consequently, the regression estimator of d proposed by Geweke and Porter-Hudak will be asymptotically biased if the number of frequencies used in the regression is held fixed as n + m .

REVERTING THE GENDER GAP IN THE BRAZILIAN EDUCATION SYSTEM IN THE 20 TH CENTURY. The reduction of the gender gap and the improvement in female access to education were explicit objectives of the IV Conference on Women (1995), of the World Education Forum (2000) and of the Millennium Summit (2000). All International Conferences promoted by the United Nations Organization (UN) recommend actions to eradicate discrimination against women in all fields of activity, especially education. The gender gap and the education deficit among women have always been part of the Brazilian reality. However, women have been able to eliminate and reverse this gap throughout the 20th century. The main purpose of this article is to analyze when the reversion of the gender gap in Brazilian education occurred. In order to do so, we will present information obtained from demographic censuses from 1960 to 2000, based on schooling levels disaggregated by gender and birth cohorts. This methodology will allow us to track the evolution of the gender gap in birth cohorts after 1890 until 1995. GENDER -WOMEN -FORMAL EDUCATION -SEX DIFFERENCES 2The gender gap in education occurs when there are systematic differences in schooling levels between men and women. It is a useful measure for providing evidence of the inequalities that exist between the sexes in terms of access to school. For most of the 20 th century the gender gap in Brazilian education occurred because men's literacy rates and other levels of education were higher than those of women. According to approaches to gender, differences in educational levels are not the result of any biological characteristics but come from the historical and structural conditions that have shaped each society. In almost all countries in the world there were always large barriers preventing women from having access to school. Some countries have managed to break down these barriers, but in others there is still a long battle ahead.Reduction in the gender gap and greater access of women to education were explicit objectives of the IV Woman's Conference (1995), the World Education Forum (2000) and the Millennium Goals (2000). All the international conferences promoted by the United Nations (UN) over the last ten years have started from the principle that to achieve a fairer and more prosperous world it is necessary to eliminate discrimination against females in all fields of activity, especially in education. By doing so, women will have greater status and autonomy, or in other words, greater empowerment.The gender gap and a shortfall in education for women were part of the Brazilian reality for almost 450 years. According to Alves (2003), reversal of the gender gap in education was the biggest conquest of Brazilian women in the last century. This female triumph, however, has still not been sufficient to reverse the gender gap in the labor market, in access to income and property, in parliamentary representation, etc. Victory in the educational field has still not met with the same success in othe...

In Geweke and Porter-Hudak's estimator of the memory parameter of a long-memory process, a critical choice the user must make is the number of frequencies, M , to be used in the regression of the log periodogram on log frequency. This choice is critical in practice because by simply varying M for a given data set it is often possible to obtain a very wide range of values of the estimator. Although Geweke and Porter-Hudak have found that choosing M to be the square root of the sample size gave good results in simulation, they gave no theoretical justification for this choice. Here, we propose automatic criteria for selecting M, and another tuning constant used in related estimates of the memory parameter, based on frequency domain cross-validation. We provide some theoretical and heuristic justification for the proposed criteria. In a simulation study, we compare some of the resulting automatic methods of estimating the memory parameter with existing non-automatic ones.

principalmente do norte do Japão, que no inverno procuravam trabalho mais ao sul. Hoje, no Japão, este termo é aplicado aos trabalhadores estrangeiros temporários que estão naquele país com o intuito de ganhar dinheiro (exclui os expatriados -trabalhadores de firmas estrangeiras). No Brasil, a apropriação do termo ganhou contornos mais específicos, referindo-se aos brasileiros de origem nipônica e suas famílias

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