Social interaction

Due to the dynamic nature of P2P systems, it is impossible to keep an accurate
history of the transactions that take place while avoiding security attacks
such as whitewashing and collusion, and abuse such as freeriding . This is why it
is important to develop a mechanism that rewards cooperative peers and punishes
misbehaving peers. Modeling P2P networks as social structures can allow incentive
mechanisms to be used that prevent the negative behaviors mentioned. In this thesis,
we extend a social network algorithm to include credit transfer between peers in
order to reduce the path length of queries. We also develop a selection strategy that
involves different aspects of peer interactions in P2P networks, which is promoted by
our credit transfer mechanism that discourages misbehaving peers by taking away
credits that they have with good peers and transferring them to more cooperative
ones. The simulation results show that our algorithm is effective in reducing the
debt between peers, meaning that peers become more cooperative, and shortening
the average path length to a satisfied query while increasing delivery ratio.

The goal of this study was to test the gender self-socialization model (GSSM). This
model suggests that gender identity motivates children to strive for cognitive consistency
between their gender stereotypes and their self-efficacy for those stereotypes. This study
presents a novel approach to stereotype assessment by focusing on children's
idiosyncratic stereotypes (as opposed to number of commonly shared stereotypes, which
do not provide detailed information about the types of stereotypes individual children
hold). Participants were 305 children in grades three through eight (Mage = 10.8 years).
Independent variables included children's stereotypes of 62 contextually tagged
behaviors and gender identity (comprising five dimensions). Interactive influences of
children's stereotypes and gender identity on self-efficacy were investigated. As
expected, stereotypes and gender identity worked together to predict children's self-efficacy perception for the 62 behaviors. These findings suggest that the role of gender
identity is important in the adoption of personally held gender stereotypes.

How one behaves after interacting with a friend may not be the same as before
the interaction began What factors a ect the formation of social interactions
between people and, once formed, how do social interactions leave lasting changes on
individual behavior? In this dissertation, a thorough review and conceptual synthesis
is provided Major features of coordination dynamics are demonstrated with
examples from both the intrapersonal and interpersonal coordination literature that
are interpreted via a conceptual scheme, the causal loops of coordination dynamics
An empirical, behavioral study of interpersonal coordination was conducted to
determine which spontaneous patterns of coordination formed and whether a remnant
of the interaction ensued ("social memory") To assess social memory in dyads, the
behavior preceding and following episodes of interaction was compared In the
experiment, pairs of people sat facing one another and made continuous flexion-extension finger movements while a window acted as a shutter to control
whether partners saw each other's movements Thus, vision ("social contact") allowed
spontaneous information exchange between partners through observation Each trial consisted of three successive intervals lasting twenty seconds: without social contact
("me and you"), with social contact ("us"), and again without ("me and you")
During social contact, a variety of patterns was observed ranging from phase coupling
to transient or absent collective behavior Individuals also entered and exited social
coordination differently In support of social memory, compared to before social
contact, after contact ended participants tended to remain near each other's
movement frequency Furthermore, the greater the stability of coupling, the more
similar the partners' post-interactional frequencies were Proposing that the
persistence of behavior in the absence of information exchange was the result of prior
frequency adaptation, a mathematical model of human movement was implemented
with Haken-Kelso-Bunz oscillators that reproduced the experimental findings, even
individual dyadic patterns Parametric manipulations revealed multiple routes to
persistence of behavior via the interplay of adaptation and other HKB model
parameters The experimental results, the model, and their interpretation form the
basis of a proposal for future research and possible therapeutic applications

This study surveyed over 500 persons. It examined whether the physical distance dimension of our social world or "social space" is still a force in shaping the interaction between people when modern transportation and communication makes interaction with distant others more feasible. Using both oral, and mass interviews, participants were asked to describe the character, frequency of contact, importance, and distance of their contacts within a 24-hour period. As predicted by Latane's (1981) social impact theory, the bulk of the relationships occurred at close distances. Over two-thirds of the relationships occurred at distances of 10 niles or less. Relationship type affected the distance, frequency of contact, and importance of relationships significantly. "Partners" had higher frequencies of contact and shorter reported distance than either relatives or friends. A positive relationship between importance and distance seems to indicate that some far contacts can be maintained.

Three studies use interaction in groups to test macro-level phenomena of the type predicted by computer simulations of dynamic social impact theory, an interactive, reciprocal, and recursive extension of Latane's (1981) theory of social impact, which specifies how individuals are affected by their social environment. A key prediction of dynamic social impact theory is that such phenomena as clustering and polarization of attitudes will emerge from social interactions among spatially distributed people. Study One, using a group of 24 people corresponding with their neighbors about an attitudinal topic, found both substantial polarization and a suggestive tendency toward clustering. Studies Two and Three, using 192 people organized into 48 24-person groups, provide strong empirical support for the emergence of clustering and incomplete polarization, and extend the findings to two alternative spatial structures. As predicted, a control geometry, involving random connections without any spatial organization, failed to produce clustering. Directions for future research are discussed.

The current study examined changes in mother-child and father-child relationships of 210 participants in a 3-year longitudinal study during the 6th through the 8th grade. In each relationship, latent growth curve models found that negativity had a gradual increase over the course of early adolescence, while the change in positivity during this period depended on the initial levels of positivity during the 6th grade. For those high in positivity during the 6th grade, positivity remained stable from 6th to 8th grade, while for those low in positivity during the 6th grade, positivity decreased substantially during this period. In addition, an examination of the links between the relationship features and adjustment measures, such as internalizing and externalizing problems, found that models with initial rates of the relationships predicting changes in adjustment were ideal in comparison to models with both initial rates of and changes in relationships linked to changes in adjustment.

Nutrition has been implicated as an influence in the health of older adults. However, the nature of this relationship remains unclear. Dietary patterns mirror lifelong cultural and ethnic influences, and are also responsive to existing medical and economic conditions. Depression, isolation, and cognitive impairment have been associated with inadequate food intake in this age group. Recent concern about malnutrition, including obesity, has prompted a social-psychological approach to nutrition and aging research. The purpose of this investigation was to examine the relationship of self-actualization and social support to dietary quality. Data were obtained from 100 older adults, 60 to 83 years of age. Descriptive analysis of 24-hour dietary records revealed that many subjects, even those of moderate socioeconomic status, were at potential nutritional risk. Calcium, folacin, and zinc were below two-thirds of the Recommended Dietary Allowances. In addition, inadequate intakes of kilocalories and dietary fiber were observed. Small but significant associations were found between the predictor variables and dietary quality. Self-actualization, which was measured by the Personal Orientation Inventory, and social support, which was assessed by the Nutrition Support Questionnaire, accounted for no more than 10% of the variance in dietary quality. Furthermore, except for support from family, friends, and neighbors, relationships were not consistently observed for all measures of the criterion variable, which was defined by individual nutrient adequacy scores and an overall index. Within the exploratory context of the study, several intervening variables were examined. Education and decisions to make dietary changes appeared to positively influence self-actualization and dietary quality. Loneliness, depression, and chronic disease were among a cluster of variables that tended to exert a negative influence on self-actualization. A theoretical model of dietary quality in later adulthood was proposed. Further research is needed to test these linkages empirically.

Economic game theory has been a challenge to traditional models of selfish human nature. Resource acquisition games, such as the dictator game, which have been primarily played by adults, have revealed that humans are inclined to share even when it is not in their best interest to do so. Few studies have been conducted on the development of resource distribution in children, and fewer still have explored the effect of context and level of involvement of a second player in such games. In the current study, 179 children from kindergarten, first, and second grades participated in a modified dictator game with another player. Children were randomly assigned to one of four conditions; a control condition, where they played individually with an anonymous player, or one of three experimental conditions with two players who each played with varying levels of involvement with the second player. It was found that kindergarteners shared significantly less across conditions than first and second graders, with first and second graders sharing similar amounts. The presence of another player significantly increased the amount of sharing for all grades. Additionally, second players shared significantly less than first players. Developmental and contextual patterns of sharing are discussed.

System justification theorists have proposed that people are motivated to view their political, economic, and social circumstances as desirable, necessary, and fair (e.g., Jost, Nosek & Banaji, 2004). Despite more than 15 years of system justification research, the meaning of fairness within this context has not been investigated directly. Over the past several decades three major criteria have been identified as contributing to people's perceptions of fairness: distributive justice, procedural justice, and one's own idiosyncratic set of personal values. Focusing on the last two, we reasoned that values are represented more abstractly than is information about procedural fairness, and that the relative weight of values versus procedures should increase at higher levels of mental construal. Whereas information about procedures is often seen as providing a basis for the acceptance of undesirable outcomes, judgments based on personal conceptions of right and wrong are considered to be independent from "establishment, convention, rules, or authority" (Skitka & Mullen, 2008, p. 531), and are therefore unlikely to be used in a motivated defense of the status quo. We therefore hypothesized that system justification would be most likely to occur in conditions where procedures are most salient (i.e., at low levels of construal). However, despite using manipulations of the system justification motive that have previously been successful, and working with issues similar to those used in previous work, we were unable to produce the typical system justification pattern of results. Possible reasons for this are discussed.

Self-concept stability was tested in three studies to examine the relationship between stability in one's self-concept and the ability to adapt to changes in the social environment. Much of the literature on the topic of self-stability emphasizes the functional benefits of stability and the negative outcomes associated with instability. Dynamical systems theory purports however that stability in a dynamical system is indicative of a loss of complexity that limits the range of the systems behavior. Accordingly, this series of studies tests the idea that a stable self-system may have a more limited range of behaviors than unstable self-systems and this may have implications for adapting to changes in one's social environment. The overarching hypothesis is that compared to those with less stable self-views, those with stable self-views will demonstrate lower levels of flexibility of behavior in response to changing social demands. Study 1 assessed the dynamics of participants' evaluations by asking them to complete a self-descriptive recording and evaluate their self-descriptions using the mouse paradigm procedure. Participants also completed a series of questionnaires assessing personality factors and behavioral and cognitive flexibility. Study 2 expanded on the first study by adding a well-validated measure of self-esteem stability and a social conceptualization of behavioral flexibility. Study 3 tested participants' willingness to demonstrate behavioral flexibility in an actual social situation and examined the effects of stress on the relationship between stability and flexibility.