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2003 - American Association for Public Opinion Research Words: 300 words || 
1. Peytcheva, Emilia. and Peytchev, Andy. "Dealing with Distributions of Behavior Frequencies – an Example with Alcohol Use" Paper presented at the annual meeting of the American Association for Public Opinion Research, Sheraton Music City, Nashville, TN, Aug 16, 2003 <Not Available>. 2019-04-18 <>
Publication Type: Conference Paper/Unpublished Manuscript
Review Method: Peer Reviewed
Abstract: Frequencies of behaviors reported by the respondent are very commonly used in multiple regression and SEM. However, behaviors such as alcohol use, even when “conveniently” categorized in uneven frequency ranges still remain with distributions strongly deviating from normal, often resembling that of count variables. Although estimates are usually attenuated due to this erroneous assumption, the incorporation of merely weights without accounting for the complex sample design often results in underestimation of standard errors. Hence, when both of these errors are committed, one finds wrong estimates to be statistically significant. Furthermore, as frequencies are truncated at the lower end by zero, only the positive part of the distribution is observed, necessitating a test whether the non-users are part of the same or a different overlapping parent population.
The purpose of this paper is to build a model explaining frequency of alcohol use by adolescents in grades 7-12 (excluding non-drinkers) using the National Longitudinal Study of Adolescent Health sample in wave 1 (1995) and use this model to (1) contrast parameter estimates, standard errors, and substantive interpretations/conclusions from weighted least squares (WLS), WLS with incorporation of the complex survey design, and Poisson regression accounting for the complex survey design, (2) compare parameter estimates between a logistic regression on drinkers and non-drinkers and a Poisson regression on the drinkers to determine whether a Tobit or a Mixture models should be employed, and (3) dependent upon results from (1) and (2) to show results from a Selection/Mixture model. Explanatory variables in the model are composites of selected items from the Delinquency, Violence, Self-esteem scales, and demographic variables. Finally, based on these findings, implications of using WLS on such data are discussed in the context of specific differences in estimates and conclusions between WLS and the statistically more appropriate model.

2007 - American Sociological Association Pages: 19 pages || Words: 996 words || 
2. Sanchez, Jesus. "Personal network characteristics associated with frequency of injection among a cohort of Hispanic injectors in South Florida" Paper presented at the annual meeting of the American Sociological Association, TBA, New York, New York City, Aug 11, 2007 Online <PDF>. 2019-04-18 <>
Publication Type: Conference Paper/Unpublished Manuscript
Abstract: The purpose of this study is to extend existing knowledge on the effect of personal networks on HIV-related risk behaviors, particularly, the frequency of injection among a cohort of Hispanic injectors in South Florida.
A stratified network based sample of 240 heroin users was recruited from February 2005 to September 2006 from communities in South Florida known for high drug use. After screening for eligibility, participants were administered a structured questionnaire that included basic sociodemographic information, drug use history, personal network, and lifestyle (including HIV risk behavior practices) characteristics.
Logistic regression was utilized to identify those personal network characteristics that make a heroin injector more likely to increase frequency of injection. Personal network size, presence of heroin injectors in personal network, having sexual partners who were injectors, and living with injectors increased the likelihood of increasing frequency of injection.
Personal network characteristics constitute risk factors for increasing injection independent of those individual risk behaviors traditionally highlighted by studies and prevention interventions. In contrast to the abundance of individual-based interventions and their moderate effectiveness, comparatively few network based interventions have been implemented despite growing evidence that indicates that social networks provide a natural frame for interventions designed to interrupt the transmission of HIV infection and to change values, beliefs, and behaviors that increase or reduce HIV risk.

2006 - XVth Biennial International Conference on Infant Studies Words: 318 words || 
3. de Heering, Adélaïde., turati, chiara., Rossion, Bruno., Bulf, Hermann., Goffaux, Valérie. and Simion, Francesca. "Newborns' face recognition is based on low spatial frequencies" Paper presented at the annual meeting of the XVth Biennial International Conference on Infant Studies, Westin Miyako, Kyoto, Japan, Jun 19, 2006 <Not Available>. 2019-04-18 <>
Publication Type: Individual Poster
Abstract: Background and Aims: Newborns are able to recognize individual faces (e.g. Bushnell et al., 1989; Pascalis & de Schonen, 1994) but little is known about the kind of visual information they rely on to perform this task. Based on the functional properties of the visual system at birth, as described by the newborns’ contrast sensitivity function (Acerra et al., 2002; Atkinson et al., 1977; Banks & Ginsburg, 1985), it may be hypothesized that low spatial frequencies play a critical role in driving newborns’ face recognition.
Methods: Two experiments were conducted testing newborn infants with filtered face images and the habituation technique. Spatial frequencies were obtained applying two different cutoff points: a 1 cycle per degree (cpd) cutoff, that corresponded to the threshold of newborns’ visual acuity (Exp. 1), and a 0.5 cpd cutoff, that was chosen so that both the lowpass and the bandpass versions of the stimuli contained half of the frequencies comprised in the range to which the newborns’ visual system is sensitive (Exp. 2).
Key Results: In Exp. 1, newborns were able to recognize the image of a real face to which they have been habituated in the lowpass condition (LSF Group, < 1cpd filtering), but not in the highpass condition (HSF Group, > 1 cpd filtering). In Exp. 2, again newborns discriminated between the habituated and the novel face in the lowpass condition (LSF Group, < 0.5 cpd filtering) but not in the highpass condition (HSF group; between 0.5 and 1 cpd).
Conclusions: Results provide empirical support to the hypothesis of an LSF advantage in individual face recognition at birth. Within the range of visuo-perceptual information that are detected and processed at birth (0 to 1 cpd), only the coarser visual cues conveyed by 0 to 0.5 cpd low spatial frequencies provide the newborn with critical source of information for recognizing faces. This LSF dominance may constitute the basis for the development of configural face processing.

2008 - Association for Education in Journalism and Mass Communication Pages: 32 pages || Words: 8087 words || 
4. Matthes, Jorg., Wirth, Werner., Schemer, Christian. and Pachoud, Nadine. "Tiptoe or Tackle? How Product Placement Prominence and Exposure Frequency Moderate the Mere Exposure Effect." Paper presented at the annual meeting of the Association for Education in Journalism and Mass Communication, Marriott Downtown, Chicago, IL, Aug 06, 2008 Online <APPLICATION/X-PDF>. 2019-04-18 <>
Publication Type: Conference Paper/Unpublished Manuscript
Abstract: According to the mere exposure effect (Zajonc 1968), the mere unreinforced presentation of product placements can increase brand liking. In an experiment, we manipulated placement prominence and placement frequency for an externally and internally valid stimulus. As results indicate, a mere exposure effect can only be observed for frequently presented subtle placements, but not for prominent placements. The reason is that prominent placements lead to high placement recall which impedes positive attitudinal effects.

2008 - American Sociological Association Annual Meeting Pages: 25 pages || Words: 6565 words || 
5. Denvir, Paul. "Physicians’ use of candidate answers in querying patients about the quantity and/or frequency of alcohol consumption" Paper presented at the annual meeting of the American Sociological Association Annual Meeting, Sheraton Boston and the Boston Marriott Copley Place, Boston, MA, Jul 31, 2008 Online <PDF>. 2019-04-18 <>
Publication Type: Conference Paper/Unpublished Manuscript
Abstract: Using conversation analytic methodology, this analysis describes some functions and consequences of physicians’ use of candidate answers in seeking information about patients’ alcohol consumption. Patients’ efforts to balance information provision with identity management are discussed. The advantages and disadvantages of this information seeking practice in medical consultations are considered, with special attention played to the implications this may have in potentially sensitive topical environments.

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