Essays on Social Preference

This thesis consists of six essays related to experimental investigation of social preference. We investigate the effects of a pure income effect on social preference in the first essay. In the second essay we explore the effects of gender in altruism and the corresponding anticipation behavior. The third essay discusses the effects of different type of rebate schemes on altruistic behavior. We study the effects of a real and a minimal identity on initiation and escalation of conflict in the fourth essay. The fifth essay investigates the effects of social cues in (anti) social behavior. The final essay tests the effects of pure framing on altruistic behavior

Identity and group conflict

We experimentally investigate the effects of real and minimal identities on group conflict. In turn we provide a direct empirical test of the hypotheses coined by Amartya Sen that the salience of a real identity escalates conflict but that of a mere classification would not do so. In a baseline treatment, two groups – East Asians and Caucasians – engage in a group contest, but information on the racial composition of the groups is not revealed. In the minimal identity treatment each group is arbitrarily given a different color code, whereas in the real identity treatment the race information is revealed. Supporting Sen’s hypotheses, we find that compared to the baseline, free-riding declines and conflict effort increases in the real identity treatment but not in the minimal identity treatment. Moreover, this occurs due to an increase in efforts in the real identity treatment by females in both racial groups

Social Search Using a Social Q&A Service: Seeking Information and Assessing Credibility.

The development of various social technologies has provided people with abundant opportunities to interact with others when seeking information. Researchers have begun to examine such interactions in the context of online information seeking using a framework of social search. However, attention has mostly focused on interactions people have with existing contacts and acquaintances, rather than with unknown people. In addition, despite increased use of social question-answering (Q&A) services to seek information, prior research has focused more on those who answer questions than those who pose them. Finally, we know relatively little about how people assess the credibility of respondents or the information they provide during such online interactions. To address these gaps, this study uses a social search framework to examine people’s information-seeking behavior and credibility assessment practices when asking questions in a social Q&A setting, with emphasis on interactions with a large number of unknown people. Seventy-eight participants were instructed to use Yahoo! Answers, the largest and most popular social Q&A service, for one week by posting questions of their own choosing while in their natural settings. A total of 406 questions was posted by participants, and in-depth interviews at the end of the week captured individual’s in situ experiences. Content analysis of interview data revealed that interacting with a large number of unknown people enabled information seekers to obtain personalized information tailored to their needs, while also allowing opportunities for more serendipitous discovery of information. People not only posted questions, but also used Yahoo! Answers to access its collection of accumulated questions and answers. In doing so, they sometimes searched for fun, not necessarily aiming to find answers to their questions. The study also identified characteristics of credibility assessment such as relativeness, crowd-assistededness, and transientness. Traditional constructs of credibility such as expertise and trustworthiness were examined, as well as two additional credibility constructs of pertinence and validity. These findings shed light on the positive effect of social interactions in social Q&A settings, and have implications for those studying information-seeking behavior and credibility assessment, as well as those seeking to improve the design of social Q&A services.PHDInformationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/110448/1/yjeon_1.pd

Classroom Readiness for Successful Inclusion: Teacher Factors and Preschool Children’s Experience with and Attitudes toward Peers with Disabilities

The current study examined (1) associations among teachers’ experiences regarding children with disabilities (i.e., education, specialized training, years of work experience), their attitudes toward disabilities, and their classroom practices in relation to inclusion and (2) associations among children’s attitudes toward peers with disabilities and child and teacher factors. Ninety-one 4- and 5-year-old children participated in an interview, and their teachers completed a survey. Teachers’ specialized training and bachelor’s degree in early childhood education (ECE) were positively associated with their inclusive practices in the classroom; teachers’ bachelor’s degree in ECE and experiences working with children with disabilities were positively associated with their attitudes toward disabilities and inclusion; and children’s perceived contact with people who have disabilities was positively associated their attitudes toward peers with disabilities. However, none of the teacher factors predicted children’s attitudes toward peers with disabilities. Early childhood teachers need more training opportunities to learn about disabilities to develop positive attitudes toward disabilities and inclusion. Providing frequent contact with people with disabilities may enhance children’s acceptance of peers with disabilities

Factors Associated with Malignant Biliary Strictures in Patients with Atypical or Suspicious Cells on Brush Cytology

Background/Aims Pathological diagnosis of biliary strictures with atypical or suspicious cells on endoscopic retrograde brush cytology and indeterminate strictures on imaging is challenging. The aim of this study was to identify markers for malignant strictures in such cases. Methods We retrospectively analyzed data collected from 146 consecutive patients with indeterminate biliary strictures on imaging who underwent endoscopic retrograde brush cytology from 2007 to 2013. Factors associated with malignant strictures in patients with atypical or suspicious cells on brush cytology were identified. Results Among the 67 patients with a malignant disease (48 cholangiocarcinoma, 6 gallbladder cancer, 5 pancreatic cancer, 5 ampulla of Vater cancer, and 3 other types), 36 (53.7%) had atypical or suspicious cells on brush cytology. Among these, the factors that independently correlated with malignant strictures were stricture length (odds ratio [OR], 5.259; 95% confidence interval [CI], 1.802– 15.294) and elevated carbohydrate antigen 19-9 (CA19-9) (OR, 3.492; 95% CI, 1.242–9.815), carcinoembryonic antigen (CEA) (OR, 4.909; 95% CI, 1.694–14.224), alkaline phosphatase (ALP) (OR, 3.362; 95% CI, 1.207–9.361), and gamma-glutamyl transpeptidase (rGT) (OR, 4.318; 95% CI, 1.512–12.262). Conclusions Elevated levels of CA19-9, CEA, ALP, and rGT and stricture length are associated with malignant strictures in patients with indeterminate biliary strictures on imaging and atypical or suspicious cells on brush cytology

Proteomic Validation of Multifunctional Molecules in Mesenchymal Stem Cells Derived from Human Bone Marrow, Umbilical Cord Blood and Peripheral Blood

Mesenchymal stem cells (MSCs) are one of the most attractive therapeutic resources in clinical application owing to their multipotent capability, which means that cells can differentiate into various mesenchymal tissues such as bone, cartilage, fat, tendon, muscle and marrow stroma. Depending on the cellular source, MSCs exhibit different application potentials according to their different in vivo functions, despite similar phenotypic and cytological characteristics. To understand the different molecular conditions that govern the different application or differentiation potential of each MSC according to cellular source, we generated a proteome reference map of MSCs obtained from bone marrow (BM), umbilical cord blood (CB) and peripheral blood (PB). We identified approximately 30 differentially regulated (or expressed) proteins. Most up-regulated proteins show a cytoskeletal and antioxidant or detoxification role according to their functional involvement. Additionally, these proteins are involved in the increase of cell viability, engraftment and migration in pathological conditions in vivo. In summary, we examined differentially expressed key regulatory factors of MSCs obtained from several cellular sources, demonstrated their differentially expressed proteome profiles and discussed their functional role in specific pathological conditions. With respect to the field of cell therapy, it may be particularly crucial to determine the most suitable cell sources according to target disease

Switching energy suppliers: it’s not all about the money

Many consumers do not take advantage of lower energy prices available in liberalized retail markets. We provide evidence to explain why consumers may leave substantial amounts of “money on the table” in this way. We observe real decisions made by over 7,000 consumers in a collective switching auction, supplemented by their responses to a survey. We identify factors which may inhibit switching and show that expectations of high switching rates in an unregulated market may be unrealistic. Our findings have important implications for the design and regulation of energy markets, including imposition of price caps on “default” retail tariffs in 2019 in the UK and parts of Australia

EFFECTS OF WALKING SPEED AND AGE ON THE DIRECTIONAL STRIDE REGULARJRY AND GAIT VARIABILITY IN TREADMILL WALKING

The purpose of this study was to assess the directional stride regularity (SR) and gait variability (GV) of data from shoe-type inertial measurement unit (IMU) sensors during levelled treadmill walking. The DynaStabtm (IMU based gait analysis system) including Smart Balance' (shoe-type data logger) was used to collect normal gait data from forty-four subjects in their 20s (n=20), 40s (n=13), and 60s (n=ll). Four different walking speeds (3, 4, 5, and 6 km/h, respectively) on a treadmill were applied for one-minute of continuous levelled walking. Only lateral kinematics (mediolateral acceleration and yawing and rolling angular velocities) revealed significant interactions from walking speed and age, demonstrating lower stride regularity and higher gait variability than the anteroposterior and vertical kinematics