Trend smoothness achieved by penalized least squares with the smoothing parameter chosen by optimality criteria

This work presents a study about the smoothness attained by the methods more frequently used to choose the smoothing parameter in the context of splines: Cross Validation, Generalized Cross Validation, and corrected Akaike and Bayesian Information Criteria, implemented with Penalized Least Squares. It is concluded that the amount of smoothness strongly depends on the length of the series and on the type of underlying trend, while the presence of seasonality even though statistically significant is less relevant. The intrinsic variability of the series is not statistically significant and its effect is taken into account only through the smoothing parameter.     

Pure Gold for Broken Bodies: Discursive Techniques Constructing Milk Banking and Peer Milk Sharing in U.S. News

Technological advances provide increased ability to transfer human tissues—blood, organs, milk—from one body to another. This article analyzes mechanisms of reality construction in U.S. news to construct shared human breast milk. Articles used typifications and human interest stories to convey participants as victims, lay heroes, and villains. Milk banking was portrayed as institutionally integrated through associations, expert testimonies, and formalized procedures, making banked milk “pure gold.” Peer sharing was portrayed as institutionally opposed through institutional warnings, expert testimonies, informal procedures, and hypothetical atrocities, making peer milk “fool's gold.” Findings suggest that “biovalue” of human milk is interconnected with institutional processing.     

Residual Kriging for Functional Spatial Prediction of Salinity Curves

Recently, several methodologies to perform geostatistical analysis of functional data have been proposed. All of them assume that the spatial functional process considered is stationary. However, in practice, we often have nonstationary functional data because there exists an explicit spatial trend in the mean. Here, we propose a methodology to extend kriging predictors for functional data to the case where the mean function is not constant through the region of interest. We consider an approach based on the classical residual kriging method used in univariate geostatistics. We propose a three steps procedure. Initially, a functional regression model is used to detrend the mean. Then we apply kriging methods for functional data to the regression residuals to predict a residual curve at a non-data location. Finally, the prediction curve is obtained as the sum of the trend and the residual prediction. We apply the methodology to salinity data corresponding to 21 salinity curves recorded at the Ciénaga Grande de Santa Marta estuary, located in the Caribbean coast of Colombia. A cross-validation analysis was carried out to track the performance of the proposed methodology.     

Appropriation of African American slang by Asian American youth1

This article explores the ways in which Asian American teenagers creatively appropriated two African American slang terms: aite and na mean. While some teens racialized slang as belonging to African Americans, other teens authenticated identities as slang speakers. Through close analysis of slang‐in‐use and particularly of the metapragmatic discussions such uses inspired, this article examines how the teens specified relationships between language, race, age, region and class, while achieving multiple social purposes, such as identifying with African Americans, marking urban youth subcultural participation, and interactionally positioning themselves and others as teachers and students of slang. As slang emerged with local linguistic capital, the teens used slang to create social boundaries not only between teens and adults, but also between each other. The discursive salience of region implicitly indexed socio‐economic status and proximity to African Americans as markers that teens drew on to authenticate themselves and others as slang speakers.     

Longitudinal Mediators of Relations Between Family Violence and Adolescent Dating Aggression Perpetration

Few longitudinal studies have examined the pathways through which family violence leads to dating aggression. In the current study the authors used 3 waves of data obtained from 8th‐ and 9th‐grade adolescents (N = 1,965) to examine the hypotheses that the prospective relationship between witnessing family violence and directly experiencing violence and physical dating aggression perpetration is mediated by 3 constructs: (a) normative beliefs about dating aggression (norms), (b) anger dysregulation, and (c) depression. Results from cross‐lagged regression models suggest that the relationship between having been hit by an adult and dating aggression is mediated by changes in norms and anger dysregulation, but not depression. No evidence of indirect effects from witnessing family violence to dating aggression was found through any of the proposed mediators. Taken together, the findings suggest that anger dysregulation and normative beliefs are potential targets for dating abuse prevention efforts aimed at youth who have directly experienced violence.     

North Americans' Attitudes Toward Illegal Drugs

Public opinion polls conducted from 1969 to 2003 found a variety of opinions on the use, possession, and legalization of marijuana. Public opinion about legalizing marijuana use is increasing, but it is also increasing toward harsher penalties for those who possess a small amount of marijuana. Public opinion regarding the legalization of illegal drugs appears to be influenced by the times. The majority of Americans increasingly believe that the country has made some progress in dealing with the problems of illegal drugs, but Americans are also reporting more difficulty within their families related to marijuana. This article examines trends based in public opinion polls on the use of marijuana in the United States and Canada and discusses the social and political history of marijuana and the biophysical effects, medical uses, definitions, and previous research related to marijuana.     

Changes in Trip Duration for Mexican Immigrants to the United States

Using the Mexican Migration Project sample, this paper explores the patterns of trip duration for Mexican immigrants to the United States and the reasons for the patterns observed. I found that the most important factors leading to changes in trip duration are US immigration policy, the conditions of the Mexican economy, and the development of social networks. It appears that the legalization of many immigrants after passage of the Immigration Reform and Control Act encouraged short-term migration, but the build-up at the US-Mexico border may have changed this pattern leading to longer duration in the United States. Furthermore, changes in the exchange rate, a devaluation of the peso relative to the dollar, for example, leads to more return migration, as immigrants are able to get more value for his dollars in Mexico. On the other hand, an expansion of networks and resources for immigrants in the United States leads to longer duration in the United States.     

Understanding calendar rhythm

Rhythm has been among the family planning methods endorsed since the start of the National Population Program in the Philippines, but it has not been given as much emphasis as the other methods such as oral contraception (OC), the IUD, and sterilization. For several years, no systematic effort was made to promote the effective use of rhythm. The 1978 Community Outreach Survey (COS) tried to determine the extent to which contraceptive methods were being used in the Outreach Project areas. The project covered 2,000 barangay service points (BSPs) with 1.76 million married couples of reproductive age (MCRA), representing 32% of the estimated total MCRA in the Philippines. The COS findings revealed that, of the total sexually active married women aged 15-49, 48% were using contraceptive methods. Of these, only 11.4% were using modern methods, 20% were using other program methods (rhythm, condom, and combination of rhythm and condom); and 16.7% were using nonprogram methods (withdrawal, abstinence, and others). When used in combination with other methods, rhythm had a monthly continuation rate of 96%; when used alone, 94%. The COS data showed that the rhythm method is practiced by a large number of Filipino couples. With the renewed interest in rhythm, it became imperative for the program to help rhythm acceptors use the method more effectively and thus reduce user failure. There continues to be need for data on the "product image" of rhythm. These include the emotions that come into play in the acceptance or rejection of rhythm, the perceived side effects as well as advantages of the method, the ways women communicate their "safe" and "unsafe" days to their husbands, the manner in which couples prevent sexual contact during "unsafe" days, and the attitude of couples toward abstinence. Among important study findings were the following: couples choose rhythm because it does not disturb the sexual act, has no side effects, and poses no religious objections; 1 of the problems of rhythm users is that they get varied explanations and instructions from service delivery personnel on the correct way to practice rhythm; and many rural women do not have a clear understanding of the menstrual cycle. Requirements of successful rhythm practice include cooperation, regular cycle, and the couple's age.     

Immigrant Trip Duration: The Case of Immigrants from Western Mexico1

This article uses data from the Mexican Migration Project to determine the factors that affect how long Mexican immigrants stay in the United States. Based on the estimates of a discrete‐time hazard model, the most important predictors of duration are the economic opportunities for immigrants in the United States, the household resources before migration, and the opportunities available at the immigrant's community of origin. The article also finds longer trip duration after the Immigration Reform and Control Act than in previous years and important differences between male and female migrants.