An investigation of the effects of IT investment on firm performance: The role of complementarity.

The concept of complementarity has been introduced into IT-based firm performance research in order to address inconsistent magnitudes of the impacts from IT investments across studies. This dissertation seeks to understand the scope of IT investment complementarities, to examine the different ways in which different complementarities impact the payoff from an IT investment, and to empirically test the effects of complementary investments in the context of investments in SCM and CRM. The knowledge-based view of the firm (KBV) is employed in order to understand a boundary and different roles of complementarity. The KBV sees organizational capabilities from the aggregation of knowledge into capabilities and the deployment of knowledge assets in the form of capabilities. Knowledge aggregation requires individuals' specialized knowledge (human capital) and the aggregation mechanisms of structural, social, and community capital. The combination of these three forms of capital, together with human capital, constitutes organizational capabilities. Once constituted, the complementary deployment of capabilities is important. Foundational capability must be in place in order for the focal IT investment to deliver value, synergistic capability amplifies the economic benefits of the focal IT investment, and management capability is managers' organizing vision and capability to successfully deploy the focal IT investment.The research findings show that three forms of structural, community, and human capital have highly significant impacts on firm performance measured by Net Cash Flow, Gross Profit, and EBITDA. Synergistic capabilities and management capabilities are found to be highly significant in moderating between three forms of capital and firm performance measurements.The data for this study were drawn from secondary data sources: Annual Reports, Press Releases, and news articles. The dependent variables are drawn from COMPUSTAT. The data collection method for the independent variables was a keyword search. The research sampling frame is confined within a single value chain however distinctively different industry categories are represented within this value chain. This sampling strategy yielded a total of 111 firms that had invested in SCM and 45 firms that had invested in CRM

The role of tags in information retrieval interaction

No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63044/1/14504503137_ftp.pd

Different Behavior of Magnetic Impurities in Crystalline and Ammorphous States of Superconductors

It has been observed that the effect of magnetic impurities in a superconductor is drastically different depending on whether the host superconductor is in a crystalline or an amorphous state. Based on the recent theory of Kim and Overhauser (KO), it is shown that as the system is getting disordered, the initial slope of the $T_{c}$ depression is decreasing by a factor $\sqrt{\ell/\xi_{0}}$, when the mean free path $\ell$ becomes smaller than the BCS coherence length $\xi_{0}$, which is in agreement with experimental findings. In addition, for a superconductor in a crystalline state in the presence of magnetic impurities the superconducting transition temperature $T_{c}$ drops sharply from about 50% of $T_{c0}$ (for a pure system) to zero near the critical impurity concentration. This {\sl pure limit behavior} was indeed found by Roden and Zimmermeyer in crystalline Cd. Recently, Porto and Parpia have also found the same {\sl pure limit behavior} in superfluid He-3 in aerogel, which may be understood within the framework of the KO theory.Comment: 7 figures, 20 pages, latex, to appear in Superconductor Science and Technolog

Impurity scattering in a d-wave superconductor

The influence of (non-magnetic and magnetic) impurities on the transition temperature of a d-wave superconductor is studied anew within the framework of BCS theory. Pairing interaction decreases linearly with the impurity concentration. Accordingly $T_{c}$ suppression is proportional to the (potential or exchange) scattering rate, $1/\tau$, due to impurities. The initial slope versus $1/\tau$ is found to depend on the superconductor contrary to Abrikosov-Gor'kov type theory. Near the critical impurity concentration $T_{c}$ drops abruptly to zero. Because the potential scattering rate is generally much larger than the exchange scattering rate, magnetic impurities will also act as non-magnetic impurities as far as the $T_{c}$ decrease is concerned. The implication for the impurity doping effect in high $T_{c}$ superconductors is also discussed.Comment: 12 pages and 1 figure, PlainTex, submitted to Mod. Phys. Lett. B, For more information, please see "http://taesan.kaist.ac.kr/~yjkim

Cultural Foundations of Contentious Democracy in South Korea

This study takes a cultural approach to examine the unstable and contentious nature of Korean democracy. Analyzing an original nationwide survey conducted in 2015, we find that the democratic and participatory culture of the Korean people underlies Korean democracy. This finding suggests substantial tension between the participatory orientation of the public and Korean representative democracy

Comparing Medical Comorbidities Between Opioid and Cocaine Users: A Data Mining Approach

Background: Prescription drug monitoring programs (PDMPs) are instrumental in controlling opioid misuse,but opioid users have increasingly shifted to cocaine, creating a different set of medical problems. Whileopioid use results in multiple medical comorbidities, findings of the existing studies reported singlecomorbidities rather than a set, and furthermore, those findings are often conflicting because of the lack ofcontrolling for other substances in the analysis when combined use of substance creates synergistic effects.On the other hand, the findings from cocaine use are mainly related to kidney and heart problems, which lackspecificity. Because medical comorbidities from opioid and cocaine use are very different, it is imperative toinvestigate medical comorbidities from opioids and cocaine in order to minimize negative effects fromPDMPs. Therefore, this study attempts to discover sets of medical comorbidities from opioid and cocaine useby controlling for other substances in the analysis.Methods: A data mining technique, association rule mining algorithm, was employed to discover sets ofmedical comorbidities using electronic medical records. This method is ideal to discover co-occurringmedical comorbidities.Findings: Opioid use was associated with a set of [high diastolic blood pressure (DBP), abnormal specificgravity], [high body mass index (BMI), low blood gas] among others. Cocaine use correlated with [highcreatine kinase (CK), high blood urea nitrogen (BUN)], [high CK, cardiopulmonary] among others.Conclusion: The findings of this study addresses some of the conflicting findings by eliminating multidrugand reports sets of medical comorbidities from opioid and cocaine us

Korean American Mothers' Perception: Investigating the Role of Cultural Capital Theory and Parent Involvement

The strongest and most consistent predictors of parent involvement at school and at home are the specific school programs and teacher practices that encourage parent involvement at school and guide parents in how to help their children at home (Dauber & Epstein, 1995). Joyce Epstein (2004) developed a framework for defining six different types of parent involvement. This framework assists educators in developing school and family partnership programs. "Schools have a vested interest in becoming true learning communities. They are now accountable for all students' learning," she writes. "To learn at high levels, all students need the guidance and support of their teachers, families, and others in the community." School improvement no longer rests solely on the shoulders of the principal, but rather takes the collaborative effort of the entire school community to increase achievement levels of all students. A major stakeholder of that community is the parents who want what is in the best interest of their children. This mixed-methods study examined the perceptions of Korean American mothers regarding their own parent involvement practices and investigated the role of Bourdieu's Cultural Capital Theory using the conceptual framework of Epstein's Parent Involvement Framework. Data for this study were collected by way of survey responses and interview probes with focus groups of six Korean American mothers. In the quantitative phase of the study, 81 mothers from a single school district in the mid-Atlantic United States were identified. The results from the quantitative phase of the study found that English proficiency had a significant impact on whether Korean American mothers engaged in parent involvement activities. Examination of the focus group responses revealed that the Korean American mothers identified English and time as major factors in determining in what types of parent involvement activities they engaged. Parent involvement is essential for promoting successful school improvement. It plays a pivotal part in school reform. Further research is recommended with larger samples of participants in rural and urban settings. In addition, future research should examine the role of fathers in parent involvement

The Use of Social Tags in Text and Image Searching on the Web.

In recent years, tags have become a standard feature on a diverse range of sites on the Web, accompanying blog posts, photos, videos, and online news stories. Tags are descriptive terms attached to Internet resources. Despite the rapid adoption of tagging, how people use tags during the search process is not well understood. There is little empirical data on the use and perceptions of tags created by those other than the searcher. Previous research on tags focused on the motivations and behaviors of taggers, although non-taggers represent a larger proportion of Web users than taggers. This study examines how people use tags, created by others, during the search process. Forty-eight subjects were each assigned four search tasks in a within-subjects study. Subjects searched for text documents and images in a controlled laboratory setting, using information retrieval interfaces differing in their incorporation of tags. User behavior and perception data were collected through search logs and interviews. Both direct and indirect uses of tags across the search process were examined. Tags are used directly when they are clicked on, resulting in a new query, while tags are used indirectly when used for judgments of relevance or to obtain additional terms for query reformulation. Tags increased interactions with the information retrieval system, as subjects issued more queries and saw more search results when using the tagged interface. For both text and image searches, tags were used for query reformulation, predictive judgment, and evaluative judgment of relevance. Subjects interacted most frequently with tags on the search results page, using them for query reformulation and predictive judgment. Tags were more likely to be used for predictive judgment in text searches than in image searches. Subjects’ understanding of tags focused on the role of tags in search, especially findability through a search engine. Tags were not uniformly perceived as being user-generated; site owners and automatic generation were mentioned as sources of tags. Several implications for the design of search interfaces and presentation of tags to support information interactions are discussed in the conclusion.Ph.D.InformationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/89816/1/kimym_1.pd