In online social networks, the audience size commanded by an organization or an individual is a critical measure of that entity’s popularity and this measure has important economic and/or political implications. Such efforts to measure popularity of users or exploit knowledge about their audience are complicated by the presence of fake profiles on these networks. In this study, analysis of 62 million publicly available Twitter user profiles was conducted and a strategy to identify automatically generated fake profiles was established. Using (...) a combination of a pattern-matching algorithm on screen-names and an analysis of update times, a reasonable number of highly reliable fake user accounts were identified. Analysis of profile creation times and URLs of these fake accounts revealed their distinct behavior relative to a ground truth data set. The characteristics of friends and followers of users in the two data sets further revealed the very different nature of the two groups. The ratio of number of followers-to-friends for ground truth users was ∼1, consistent with past observations, while the fake profiles had a median ratio ∼30, indicating that the fake users we identified were primarily focused on gathering friends. An analysis of the temporal evolution of accounts over 2 years showed that the friends-to-followers ratio increased over time for fake profiles while they decreased for ground truth users. Our results, thus, suggest that a profile-based approach can be used for identifying a core set of fake online social network users in a time-efficient manner. (shrink)

Differences in infant caregiving behavior between cultures have long been noted, although the quantified comparison of touch-based caregiving using uniform standardized methodology has been much more limited. The Parent-Infant Caregiving Touch scale was developed for this purpose and programming effects of early parental tactile stimulation on infant hypothalamic-pituitary adrenal -axis functioning, cardiovascular regulation and behavioral outcomes, similar to that reported in animals, have now been demonstrated. In order to inform future studies examining such programming effects in India, we first aimed (...) to describe and examine, using parametric and non-parametric item-response methods, the item-response frequencies and characteristics of responses on the PICTS, and evidence for cross-cultural differential item functioning in the United Kingdom and India. Second, in the context of a cultural favoring of male children in India, we also aimed to test the association between the sex of the infant and infant “stroking” in both cultural settings. The PICTS was administered at 8–12 weeks postpartum to mothers in two-cohort studies: The Wirral Child Health and Development Study, United Kingdom and the Bangalore Child Health and Development Study, India. Mokken scale analysis, parametric item-response analysis, and structural equation modeling for categorical items were used. Items for two dimensions, one for stroking behavior and one for holding behavior, could be identified as meeting many of the criteria required for Mokken scales in the United Kingdom, only the stroking scale met these criteria in the sample from India. Thus, while a comparison between the two cultures was possible for the stroking construct, comparisons for the other non-verbal parenting constructs within PICTS were not. Analyses revealed higher rates of early stroking being reported for the United Kingdom than India, but no sex differences in rates in either country and no differential sex difference by culture. We conclude that PICTS items can be used reliably in both countries to conduct further research on the role of early tactile stimulation in shaping important child development outcomes. (shrink)