Mixed spatial and nonspatial problems in location based services

With hundreds of millions of users reporting locations and embracing mobile technologies, Location Based Services (LBSs) are raising new challenges. In this dissertation, we address three emerging problems in location services, where geolocation data plays a central role. First, to handle the unprecedented growth of generated geolocation data, existing location services rely on geospatial database systems. However, their inability to leverage combined geographical and textual information in analytical queries (e.g. spatial similarity joins) remains an open problem. To address this, we introduce SpsJoin, a framework for computing spatial set-similarity joins. SpsJoin handles combined similarity queries that involve textual and spatial constraints simultaneously. LBSs use this system to tackle different types of problems, such as deduplication, geolocation enhancement and record linkage. We define the spatial set-similarity join problem in a general case and propose an algorithm for its efficient computation. Our solution utilizes parallel computing with MapReduce to handle scalability issues in large geospatial databases. Second, applications that use geolocation data are seldom concerned with ensuring the privacy of participating users. To motivate participation and address privacy concerns, we propose iSafe, a privacy preserving algorithm for computing safety snapshots of co-located mobile devices as well as geosocial network users. iSafe combines geolocation data extracted from crime datasets and geosocial networks such as Yelp. In order to enhance iSafe's ability to compute safety recommendations, even when crime information is incomplete or sparse, we need to identify relationships between Yelp venues and crime indices at their locations. To achieve this, we use SpsJoin on two datasets (Yelp venues and geolocated businesses) to find venues that have not been reviewed and to further compute the crime indices of their locations. Our results show a statistically significant dependence between location crime indices and Yelp features. Third, review centered LBSs (e.g., Yelp) are increasingly becoming targets of malicious campaigns that aim to bias the public image of represented businesses. Although Yelp actively attempts to detect and filter fraudulent reviews, our experiments showed that Yelp is still vulnerable. Fraudulent LBS information also impacts the ability of iSafe to provide correct safety values. We take steps toward addressing this problem by proposing SpiDeR, an algorithm that takes advantage of the richness of information available in Yelp to detect abnormal review patterns. We propose a fake venue detection solution that applies SpsJoin on Yelp and U.S. housing datasets. We validate the proposed solutions using ground truth data extracted by our experiments and reviews filtered by Yelp.

Ex Ante Cost Benefit Analyses of Community-Based DRR Interventions in the Caribbean

This report presents a study on the cost benefit analyses (CBA) and cost effectiveness analysis (CEA) of community-based disaster risk reduction (DRR) interventions in the Caribbean. The DRR interventions, implemented by the International Federation of Red Cross (IFRC), Port of Spain, in three Caribbean countries, Jamaica, Antigua & Barbuda, and Suriname, comprised the pilot phase of the Red Cross (RC) Project, Improving Climate Change Resilience of Caribbean Communities. This study is part of the endeavor by the DRR Program of Florida International University (FIU) and the United States Agency for International Development’s Office of the U.S. Foreign Disaster Assistance (USAID/OFDA) to develop and foster DRR measures in the Latin American and Caribbean region since 2008.

Community-based older adults' perceptions of factors that influence successful aging in place

The purpose of this study was to obtain an understanding of older adults' perceptions of independence and the factors that allow them to remain living independently in the community. A questionnaire was mailed to a random sample of 500 community-based older adults. One hundred seventy eight questionnaires were returned (36%). Respondents were asked questions related to independence, self-health rating, functional difficulties, and social supports. Most respondents indicated Mental Health (97%), Physical Health (97%), Control of choices (97%), and Social Support Systems (93%) contributed to maintaining independence in the community. Age, education, fewer chronic health conditions, and a higher self-health rating were found to be significant predictors of actual independence. Family members were identified as the primary source of assistance with advice on major life decisions and financial matters. Findings indicate age, education, health status and the social support of family and friends all play an important role for older adults to live independently in the community. Occupational therapy could be instrumental in extending the health, highest level of independent functioning, and the number of years older adults remain living in the community.

The emergence of a mass community-based ecotourism theme park : the case of Ejido Chacchoben, Quintana Roo, Mexico

In 1998, a dispute between a federal government agency and the local community of Chacchoben resulted in the emergence of a community-based ecotourism (CBE) enterprise to be fully owned and operated by the community in conjunction with a complex arrangement of agreements and partnerships with external actors. CBE is usually framed as a lower-impact, often small-scale alternative to mass tourism and as a conservation and development strategy that can hypothetically protect biologically diverse landscapes while improving the lives of marginalized peasant and indigenous communities through their participation. This case study analyzes the roles of common property land tenure and social capital and how the unique dilemma of a mass community-based ecotourism theme park emerged in Chacchoben. Findings indicate that local decisions and processes of development, conservation, and land use are affected by the complex interaction between local and external institutions and fluctuating levels of social capital.

Curriculum development in a heritage language community-based school: A Qualitative inquiry regarding a Brazilian-Portuguese program in South Florida

This research aimed to describe, understand, and discuss the curriculum development process of a Brazilian-Portuguese heritage language community-based school in South Florida. This study was guided by the following research questions: (a) What roles does this HL community-based school aim to play for its students? This investigation was also related to the subsidiary question: (b) How does this HL community-based school organize its curriculum development process? In order to explore these research questions, I observed and interviewed teachers and coordinators based on a qualitative research approach. I analyzed the interviews’ transcripts, and the program’s website with a central focus of describing and understanding their curriculum development process. Hopefully, the findings will help Brazilian and other HL community schools toward discussing and elaborating their own curriculum development, as well as to look for specific teacher training courses.

Best Practices: Lessons Learned by a South Florida Non-Profit Community Based Organization while Designing and Implementing a Career Exploration Evidence Informed Framework in Urban Communities

All A’s was designed to support of the agency’s family strengthening initiatives in South Florida. All A’s uses evidence informed strategies poised to be an inclusive curriculum that teaches self-determination and adaptive behavior skills. The framework incorporates problem based learning and adult learning theory and follows the Universal Design for Learning. Since 2012, the agency has served over 8500 youth and 4,000 adults using the framework. The framework addresses educational underachievement and career readiness in at risk populations. It is used to enhance participants AWARENESS of setting SMART goals to achieve future goals and career aspirations. Participants are provided with ACCESS to resources and opportunities for creating and implementing an ACTION plan as they pursue and ACHIEVE their goals. All A’s promotes protective factors and expose youth to career pathways in Science, Technology, Engineering and Math (STEM) related fields. Youth participate in college tours, job site visits, job shadowing, high school visits, online college and career preparation assistance, service learning projects, STEM projects, and the Winning Futures© mentoring program. Adults are assisted with résumé development; learn job search strategies, interview techniques, job shadowing experiences, computer and financial literacy programs. Adults and youth are also given the opportunity to complete industry-recognized certifications in high demand industries (food service, general labor, and construction), and test preparation for the General Educational Development Test.

Mixed Spatial and Nonspatial Problems in Location Based Services

With hundreds of millions of users reporting locations and embracing mobile technologies, Location Based Services (LBSs) are raising new challenges. In this dissertation, we address three emerging problems in location services, where geolocation data plays a central role. First, to handle the unprecedented growth of generated geolocation data, existing location services rely on geospatial database systems. However, their inability to leverage combined geographical and textual information in analytical queries (e.g. spatial similarity joins) remains an open problem. To address this, we introduce SpsJoin, a framework for computing spatial set-similarity joins. SpsJoin handles combined similarity queries that involve textual and spatial constraints simultaneously. LBSs use this system to tackle different types of problems, such as deduplication, geolocation enhancement and record linkage. We define the spatial set-similarity join problem in a general case and propose an algorithm for its efficient computation. Our solution utilizes parallel computing with MapReduce to handle scalability issues in large geospatial databases. Second, applications that use geolocation data are seldom concerned with ensuring the privacy of participating users. To motivate participation and address privacy concerns, we propose iSafe, a privacy preserving algorithm for computing safety snapshots of co-located mobile devices as well as geosocial network users. iSafe combines geolocation data extracted from crime datasets and geosocial networks such as Yelp. In order to enhance iSafe's ability to compute safety recommendations, even when crime information is incomplete or sparse, we need to identify relationships between Yelp venues and crime indices at their locations. To achieve this, we use SpsJoin on two datasets (Yelp venues and geolocated businesses) to find venues that have not been reviewed and to further compute the crime indices of their locations. Our results show a statistically significant dependence between location crime indices and Yelp features. Third, review centered LBSs (e.g., Yelp) are increasingly becoming targets of malicious campaigns that aim to bias the public image of represented businesses. Although Yelp actively attempts to detect and filter fraudulent reviews, our experiments showed that Yelp is still vulnerable. Fraudulent LBS information also impacts the ability of iSafe to provide correct safety values. We take steps toward addressing this problem by proposing SpiDeR, an algorithm that takes advantage of the richness of information available in Yelp to detect abnormal review patterns. We propose a fake venue detection solution that applies SpsJoin on Yelp and U.S. housing datasets. We validate the proposed solutions using ground truth data extracted by our experiments and reviews filtered by Yelp.

Globalization of the Internet: Convergence or a multicultural community?

The purpose of this dissertation was to investigate cross-cultural differences in the use of the Internet. Hofstede's model of national culture was employed as the theoretical foundation for the analysis of cross-cultural differences. Davis's technology acceptance model was employed as the theoretical foundation for the analysis of Internet use. ^ Secondary data from an on-line survey of Internet users in 22 countries conducted in April 1997 by the Georgia Tech Research Corporation measured the dependent variables of Internet use and the independent variables of attitudes toward technology. Hofstede's stream of research measured the independent variables of the five dimensions of national culture. ^ Contrary to expectations, regression analyses at the country level of analysis did not detect cultural differences. As expected, regression analyses at the individual level of analysis did detect cultural differences. The results indicated that perceived usefulness was related to the frequency of Internet shopping in the Germanic and Anglo clusters, where masculinity was high. Perceived ease of use was related to the frequency of Internet shopping in the Latin cluster, where uncertainty avoidance was high. Neither perceived usefulness nor perceived ease of use was related to the frequency of Internet shopping in the Nordic cluster, where masculinity and uncertainty avoidance were low. ^ As expected, analysis of variance at the cluster level of analysis indicated that censorship was a greater concern in Germany and Anglo countries, where masculinity was high. Government regulation of the Internet was less preferred in Germany, where power distance was low. Contrary to expectations, concern for transaction security. was lower in the Latin cluster, where uncertainty avoidance was high. Concern for privacy issues was lower in the U.S., where individualism was high. ^ In conclusion, results suggested that Internet users represented a multicultural community, not a standardized virtual community. Based on the findings, specific guidance was provided on how international managers and marketers could develop culturally sensitive strategies for training and promoting Internet services. ^

Living positive: Life in community among Puerto Rican men living with HIV in Boston

Negative experiences of stigmatization, discrimination, and rejection are common among people living with HIV in the United States, and particularly when they are also members of a minority group. Some three decades after the first cases of AIDS were identified, people infected with HIV continue to be perceived and characterized negatively. While an HIV/AIDS diagnosis is typically associated with negativity, this study investigates the extent to which collective experiences among HIV-positive people result in healthy responses and positive social adjustment. This study is focused on the ways in which HIV-positive Puerto Rican men in Boston live positive despite being diagnosed with HIV. Rather than wrapping themselves in the social stigma of HIV and the isolation that entails, they participate in processes that affirm themselves and their peers. In so doing, they help generate both healthy and meaningful lives for themselves and others. The study examines the process in which Puerto Rican men living with HIV in Boston participate, promote, and reaffirm an HIV community, la comunidad, as a social entity with a unique culture and identity. This study also investigates how this community influences, supports, and encourages the adoption of positive transformations for living long term with HIV. On the basis of nine months of field research, this qualitative study employed both focus groups and interviews with fifty HIV-positive Puerto Rican men in Boston. These men were recruited, using convenience sampling, from different community-based organizations (CBOs) that provide HIV/AIDS services in Boston. The study finds that HIV-positive Puerto Rican men in Boston build community, not in response to social exclusion, but built on shared positive practices and strategies for living healthy with HIV. These men come together to negotiate and form a unique cultural community expressed in norms, beliefs, and practices that, although centered on HIV, are designed for living healthy. These expressions reaffirm a sense of community in everyday settings and transform the lives of these men with positive behaviors and healthy lifestyles. The findings reveal that this transformation takes place in the context of a community, with the support, encouragement, and at times, policing of others. La comunidad is where the lives of these men are transformed as they learn, adopt, and experience living positive with HIV.

The effect of a breakfast program on nutritional status, quality of life, and health care use among frail homebound older adults

The population of older adults is rapidly increasing, creating a need for community services that assist vulnerable older adults in maintaining independence and quality of life. Recent evidence confirms the importance of food and nutrition in reaching this objective. The Elderly Nutrition Program (ENP) is part of a system of federally funded community based programs, authorized through the Older Americans Act. ENP services include the home-delivered meals program, which targets frail homebound older adults at nutritional risk. Traditionally, ENP services provide a noon meal 5 days/week. This study evaluated the impact of expanding the home-delivered meals service to include breakfast + lunch, on the nutritional status, quality of life and health care utilization of program participants. ^ This cross-sectional study compared 2 groups. The Breakfast group (n = 167) received a home-delivered breakfast + lunch, 5 days/week. The Comparison group (n = 214) received lunch 5 days/week. Participants, recruited from 5 ENP programs, formed a geographically, racially/ethnically diverse sample. Participants ranged in age from 60–100 years, they were functionally limited, at high nutritional risk, low income, and they lived alone and had difficulty shopping or preparing food. Participant data were collected through in-home interviews and program records. A 24-hour food recall and information on participant demographics, malnutrition risk, functional status, health care use, and applicable quality of life factors were obtained. Service and cost data were collected from program administrators. ^ Breakfast group participants had greater energy/nutrient intakes (p < .05), fewer health care contacts (p < .05), and greater quality of life measured as food security (p < .05) and fewer depressive symptoms (p < .05), than comparison group participants. These benefits were achieved for $1.30/person/day. ^ The study identified links from improvements in nutritional status to enhanced quality of life to diminished health care utilization and expenditures. A model of health, loneliness, food enjoyment, food insecurity, and depression as factors contributing to quality of life for this population, was proposed and tested (p < .01). ^ The breakfast service is an inexpensive addition to traditional home-delivered meals services and can improve the lives of frail homebound older adults. Agencies should be encouraged to expand meals programs to include a breakfast service. ^

Social funds as a strategy for poverty reduction in Jamaica: An exploratory study

This study explored the relationship between social fund projects and poverty reduction in selected communities in Jamaica. The Caribbean nation's social fund projects aim to reduce “public” poverty by rehabilitating and expanding social and economic infrastructure, improving social services, and strengthening organizations at the community level. Research questions addressed the characteristics of poverty-focused social fund projects; the nexus between poverty reduction and three key concepts suggested by the literature— community (citizen) participation, social capital, and empowerment; and the impact of the projects on poverty. ^ In this qualitative study, data were collected and triangulated by means of in-depth, semi-structured interviews, supplemented by key informant data; non-participant observation; and document reviews. Thirty-four respondents were interviewed individually at eight rural and urban sites over a period of four consecutive months, and 10 key informants provided supplementary data. Open, axial, and selective coding was used for data reduction and analysis as part of the grounded theory method, which included constant comparative analysis. The codes generated a set of themes and a substantive-formal theory. Findings were crosschecked with interview respondents and key informants and validated by means of an audit trail. ^ The results have revealed that the approach to poverty reduction in social fund-supported communities is a process of development-focused collaboration among various stakeholders. The process encompasses four stages: (1) identifying problems and priorities, (2) motivating and mobilizing, (3) working together, and (4) creating an enabling environment. The underlying stakeholder involvement theory posits that collaboration increases the productivity of resources and creates the conditions for community-driven development. In addition, the study has found that social fund projects are largely community-based, collaborative, and highly participatory in their implementation, as well as prescription-driven, results-oriented, and leadership-dependent. Further, social capital formation across communities was found to be limited, and in general, the projects have been enabling rather than empowering. The projects have not reduced poverty per se; however, they have been instrumental in improving conditions that were concomitants of poverty. ^

Maltreatment, psychiatric symptoms and human immunodeficiency virus/sexual transmitted infection risk behavior among youth with alcohol and other drug use problems: A person-centered analysis

Multi-problem youth undergoing treatment for substance use problems are at high behavioral risk for exposure to sexually transmitted infections (STIs), including human immunodeficiency virus (HIV). Specific risk factors include childhood adversities such as maltreatment experiences and subsequent forms of psychopathology. The current study used a person-centered analytical approach to examine how childhood maltreatment experiences were related to patterns of psychiatric symptoms and HIV/STI risk behaviors in a sample of adolescents (N = 408) receiving treatment services. Data were collected in face-to-face interviews at two community-based facilities. Descriptive statistics and Latent Profile Analysis (LPA) were used to (a) classify adolescents into groups based on past year psychiatric symptoms, and (b) examine relations between class membership and forms of childhood maltreatment experiences, as well as past year sexual risk behavior (SRB). ^ LPA results indicated significant heterogeneity in psychiatric symptoms among the participants. The three classes generated via the optimal LPA solution included: (a) a low psychiatric symptoms class, (b) a high alcohol symptoms class and (c) a high internalizing symptoms class. Class membership was associated significantly with adolescents’ self-reported scores for childhood sexual abuse and emotional neglect. ANOVAs documented significant differences in mean scores for multiple indices of SRB indices by class membership, demonstrating differential risk for HIV/STI exposure across classes. The two classes characterized by elevated psychiatric symptom profiles and more severe maltreatment histories were at increased behavioral risk for HIV/STI exposure, compared to the low psychiatric symptoms class. The high internalizing symptoms class reported the highest scores for most of the indices of SRB assessed. The heterogeneity of psychiatric symptom patterns documented in the current study has important implications for HIV/STI prevention programs implemented with multi-problem youth. The results highlight complex relations between childhood maltreatment experiences, psychopathology and multiple forms of health risk behavior among adolescents. The results underscore the importance of further integration between substance abuse treatment and HIV/STI risk reduction efforts to improve morbidity and mortality among vulnerable youth. ^

An interview study of community college student perspectives on service -learning

Over the past two decades, the community college in the United States has boasted a leadership role in the movement to make education community-based and performance-oriented. This has led to an intensification in attempts to search for more innovative means to make education more experiential and relevant to students' lived experiences. ^ One such innovative program that holds promise to meet this challenge is service-learning. This paradigm attempts to relate the academic education in the classroom to community-based problems, which fits in neatly with the community-based characteristics of the community college. It promises to link ideas developed in the classroom and their practical application within the community through guided reflection. It is designed to enhance and enrich student learning of course material by combining citizenship, academic subjects, skills, and values. ^ Though many studies have been carried out in regard to the outcomes of service-learning through quantitative means, relatively few qualitative studies are available, and those available have primarily studied traditional students at four-year residential colleges or universities. Therefore, there is an urgent need to study non-traditional students' perspectives at the community college level. ^ The purpose of this study was to describe and explain the perspectives of five students at Broward Community College, Central Campus, Ft. Lauderdale, Florida. The following exploratory questions guided this study: (1) What elements constitute these students' perspectives? (2) What variables influence their perspectives? (3) What beliefs do these students hold about their service-learning experience which support or are contrary to their perspectives? ^ This ethnographic interview study was conducted over a period of twelve months and consisted of three interviews for each of the five participants. The analysis of the data was conducted following the stringent principles of ethnographic research which included constant comparative analysis. The interviews were tape recorded with the participants' permission, transcribed verbatim, and organized into categories for in-depth understanding. Furthermore, these categories were developed from the data collected and an organizational scheme for understanding and interpreting of these perspectives emerged. The researcher, as well, kept a reflective journal of the research process as part of the data set. ^ The results of this study show the need for a better grasp of the concepts of service-learning on the part of all involved with its implementation. In spite of this, all of the participants displayed gains to a greater or lesser degree in personal growth, academic skills, and citizenship skills. ^

The use of treatment process variables to differentiate between completers and dropouts for a guided self -change adolescent substance abuse intervention

This study documented differences between substance using adolescent participants who either completed or dropped out of a brief motivational intervention. Therapeutic alliance, working alliance and patient involvement were used to describe differences in treatment process ratings in a sample of majority Latino males who either (a) completed a adolescent substance abuse intervention called Alcohol Treatment Targeting Adolescents In Need (ATTAIN) or (b) dropped out after the first or second Guided Self-Change therapy session. Fifteen-minute segments were copied from the midpoint of previously recorded audio-tapes of Guided Self-Change therapy sessions. Raters were trained to a criterion level of interrater reliability for both the Working Alliance Inventory-Short and Vanderbilt Psychotherapy Process Scale. Correlations among Working Alliance Inventory- Short and Vanderbilt Psychotherapy Process Scale subscales reflected a general similarity in the assignment of ratings to client-therapist dyads. Findings underscore why these concepts are often used interchangeably in the treatment process literature. The Vanderbilt Psychotherapy Process Scale patient participation subscale demonstrated substantial empirical differentiation from overall therapeutic alliance. Discriminant function analysis demonstrated the Working Alliance Inventory-Short goal subscale and the Vanderbilt Psychotherapy Process Scale patient participation and therapist warmth and friendliness subscales as successful classifiers of groups of mostly Latino youth based on completion status. Follow-up logistic regression analyses confirmed major findings and successfully predicted group membership. Treatment process constructs can be used as clinical tools to identify participants who may be susceptible to dropping out of treatment services. Further investigation of treatment process may enhance understanding of the influence of alliance between clients and Guided Self-Change therapists. Investigating the role of treatment process as a critical component of brief motivational interventions for substance-using adolescents will inform both practitioners and researchers regarding the effectiveness of community-based substance abuse interventions for adolescents.