3,643 research outputs found

    Releasing Individually Identifiable Microdata with Privacy Protection Against Stochastic Threat: An Application to Health Information

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    The ability to collect and disseminate individually identifiable microdata is becoming increasingly important in a number of arenas. This is especially true in health care and national security, where this data is considered vital for a number of public health and safety initiatives. In some cases legislation has been used to establish some standards for limiting the collection of and access to such data. However, all such legislative efforts contain many provisions that allow for access to individually identifiable microdata without the consent of the data subject. Furthermore, although legislation is useful in that penalties are levied for violating the law, these penalties occur after an individual’s privacy has been compromised. Such deterrent measures can only serve as disincentives and offer no true protection. This paper considers security issues involved in releasing microdata, including individual identifiers. The threats to the confidentiality of the data subjects come from the users possessing statistical information that relates the revealed microdata to suppressed confidential information. The general strategy is to recode the initial data, in which some subjects are “safe” and some are at risk, into a data set in which no subjects are at risk. We develop a technique that enables the release of individually identifiable microdata in a manner that maximizes the utility of the released data while providing preventive protection of confidential data. Extensive computational results show that the proposed method is practical and viable and that useful data can be released even when the level of risk in the data is high

    An Alternative Strategy for Building Sales of Computers: Generic Advertising

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    Frequent upgrading and aggressive price-cutting have become standard practice in the computer sector. While necessitated in part by declining production costs and a highly competitive market, these strategies have also served to make computers more affordable, growing the size of the overall market. Recently downturns in the sales of computers motivate us to examine the impact of these strategies on overall sales growth. We find evidence to suggest that excessive upgrading and overly aggressive price-cutting can be detrimental to overall sales growth. We also find that the computer sector exhibits characteristics that suggest that generic advertising would be an effective mechanism to enhance overall sales growth

    How Multinational Corporations Use Information Technology to Manage Global Operations

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    Despite a generally-acknowledged importance of information technology (IT) in enabling global strategy and a broad understanding of the manner in which IT enhances coordination and reduces cost, few studies have focused precisely on how multinational corporations (MNCs) use IT to facilitate globalization. To address this gap in the literature, we conduct a case study across four large MNCs, and use primary data to develop theoretical propositions on the characteristics of products, processes and customers that impact the ways in which MNCs use IT to manage their global operations

    Organ preservation and survival by clinical response grade in patients with rectal cancer treated with total neoadjuvant therapy: A secondary analysis of the OPRA randomized clinical trial

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    IMPORTANCE: Assessing clinical tumor response following completion of total neoadjuvant therapy (TNT) in patients with locally advanced rectal cancer is paramount to select patients for watch-and-wait treatment. OBJECTIVE: To assess organ preservation (OP) and oncologic outcomes according to clinical tumor response grade. DESIGN, SETTING, AND PARTICIPANTS: This was secondary analysis of the Organ Preservation in Patients with Rectal Adenocarcinoma trial, a phase 2, nonblinded, multicenter, randomized clinical trial. Randomization occurred between April 2014 and March 2020. Eligible participants included patients with stage II or III rectal adenocarcinoma. Data analysis occurred from March 2022 to July 2023. INTERVENTION: Patients were randomized to induction chemotherapy followed by chemoradiation or chemoradiation followed by consolidation chemotherapy. Tumor response was assessed 8 (±4) weeks after TNT by digital rectal examination and endoscopy and categorized by clinical tumor response grade. A 3-tier grading schema that stratifies clinical tumor response into clinical complete response (CCR), near complete response (NCR), and incomplete clinical response (ICR) was devised to maximize patient eligibility for OP. MAIN OUTCOMES AND MEASURES: OP and survival rates by clinical tumor response grade were analyzed using the Kaplan-Meier method and log-rank test. RESULTS: There were 304 eligible patients, including 125 patients with a CCR (median [IQR] age, 60.6 [50.4-68.0] years; 76 male [60.8%]), 114 with an NCR (median [IQR] age, 57.6 [49.1-67.9] years; 80 male [70.2%]), and 65 with an ICR (median [IQR] age, 55.5 [47.7-64.2] years; 41 male [63.1%]) based on endoscopic imaging. Age, sex, tumor distance from the anal verge, pathological tumor classification, and clinical nodal classification were similar among the clinical tumor response grades. Median (IQR) follow-up for patients with OP was 4.09 (2.99-4.93) years. The 3-year probability of OP was 77% (95% CI, 70%-85%) for patients with a CCR and 40% (95% CI, 32%-51%) for patients with an NCR (P \u3c .001). Clinical tumor response grade was associated with disease-free survival, local recurrence-free survival, distant metastasis-free survival, and overall survival. CONCLUSIONS AND RELEVANCE: In this secondary analysis of a randomized clinical trial, most patients with a CCR after TNT achieved OP, with few developing tumor regrowth. Although the probability of tumor regrowth was higher for patients with an NCR compared with patients with a CCR, a significant proportion of patients achieved OP. These findings suggest the 3-tier grading schema can be used to estimate recurrence and survival outcomes in patients with locally advanced rectal cancer who receive TNT. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02008656

    Integrated Block Sharing: A Win–Win Strategy for Hospitals and Surgeons

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    We consider the problem of balancing two competing objectives in the pursuit of efficient management of operating rooms in a hospital: providing surgeons with predictable, reliable access to the operating room and maintaining high utilization of capacity. The common solution to the first problem (in practice) is to grant exclusive “block time,” in which a portion of the week in an operating room is designated to a particular surgeon, barring other surgeons from using this room/time. As a major improvement over this existing approach, we model the possibility of “shared” block time, which need only satisfy capacity constraints in expectation. We reduce the computational difficulty of the resulting NP-hard block-scheduling problem by implementing a column-generation approach and demonstrate the efficacy of this technique using simulation, calibrated to a real hospital’s historical data and objectives. Our simulations illustrate substantial benefits to hospitals under a variety of circumstances and demonstrate the advantages of our new approach relative to a benchmark method taken from the recent literature

    Intense Electromagnetic Outbursts from Collapsing Hypermassive Neutron Stars

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    We study the gravitational collapse of a magnetized neutron star using a novel numerical approach able to capture both the dynamics of the star and the behavior of the surrounding plasma. In this approach, a fully general relativistic magnetohydrodynamics implementation models the collapse of the star and provides appropriate boundary conditions to a force-free model which describes the stellar exterior. We validate this strategy by comparing with known results for the rotating monopole and aligned rotator solutions and then apply it to study both rotating and non-rotating stellar collapse scenarios, and contrast the behavior with what is obtained when employing the electrovacuum approximation outside the star. The non-rotating electrovacuum collapse is shown to agree qualitatively with a Newtonian model of the electromagnetic field outside a collapsing star. We illustrate and discuss a fundamental difference between the force-free and electrovacuum solutions, involving the appearance of large zones of electric-dominated field in the vacuum case. This provides a clear demonstration of how dissipative singularities appear generically in the non-linear time-evolution of force-free fluids. In both the rotating and non-rotating cases, our simulations indicate that the collapse induces a strong electromagnetic transient. In the case of sub-millisecond rotation, the magnetic field experiences strong winding and the transient carries much more energy. This result has important implications for models of gamma-ray bursts.Comment: 28 pages, 20 figures (quality lowered to reduce sizes). Improved initial data and matching condition results in a lower, but still important, energy emission. Added appendix with a discussion on effects of transition laye

    Digital Transformation of Global Business Processes: The Role of Dual Embeddedness

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    While much existing research on MNC digital transformation has followed a linear design and implementation logic using cross-sectional data, the multiple and divergent needs of headquarters (HQ) and subsidiaries suggest that MNC digital transformation actually involves a more iterative journey. In this paper, we apply the theoretical perspective of embeddedness to better define the complexities of MNC digital transformation, and identify how HQ and subsidiaries can navigate the complexities. This paper presents a longitudinal multi-case study of five Forbes Global 2000 firms that are HQ in Europe with large subsidiaries in the U.S. We find that the process of digital transformation is significantly influenced by internal embeddedness (relationship of HQ with subsidiaries and across subsidiaries) and external embeddedness (relationship of subsidiaries with their local markets), and also by strategy, financial and technology considerations. While HQ and subsidiaries have different perspectives, an understanding of these influences can help HQ and subsidiaries navigate digital transformation

    A Model to Support IT Infrastructure Planning and the Allocation of IT Governance Authority

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    Information technology (IT) requires a significant investment, involving up to 10.5% of revenue for some firms. Managers responsible for aligning IT investments with their firm\u27s strategy seek to minimize technology costs, while ensuring that the IT infrastructure can accommodate increasing utilization, new software applications, and modifications to existing software applications. It becomes more challenging to align IT infrastructure and IT investments with firm strategy when firms operate in multiple geographic markets, because the firm faces different competitive positions and unique challenges in each market. We discussed these challenges with IT executives at four Forbes Global 2000 firms headquartered in Northern Europe. We build on interviews with these executives to develop a discrete-time, finite-horizon Markov decision model to identify the most economically-beneficial IT infrastructure configuration from a set of alternatives. While more flexibility is always better (all else equal) and lower cost is always better (all else equal), our model helps firms evaluate the tradeoff between flexibility and cost given their business strategy and corporate structure. Our model supports firms in the decision process by incorporating their data and allowing firms to include their expectations of how future business conditions may impact the need to make IT changes. Because the model is flexible enough to accept parameters across a range of business strategies and corporate structures, the model can help inform decisions and ensure that design choices are consistent with firm strategy
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