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Fundamentals of Software Patent Protection at a UniversityEverett, Christopher E 10 May 2003 (has links)
Software protection by patents is an emerging field and thus is not completely understood by software developers, especially software developers in a university setting. University inventors have to balance their publication productivity and the desire of their university to license inventions that could be profitable. This balance stems from the one-year bar on filing a U.S. patent application after public disclosure such as publications of the invention. The research provides evidence supporting the hypothesis that a university inventor can improve the protection of his or her software patent by applying certain information about patent prosecution practices and the relevant prior art. Software inventors need to be concerned about fulfilling the requirements of patent laws. Some of the methods for fulfilling these requirements include using diagrams in patent applications such as functional block diagrams, flowchart diagrams, and state diagrams and ensuring that the patent application is understandable by non-technical people. The knowledge of prior art ensures that the inventor is not "reinventing the wheel," not infringing on a patent, and understands the current state of the art. The knowledge of patent laws, diagrams, readability, and prior art enables a software inventor to take control of the protection of his or her invention to ensure that the application of this information leads to improvements during the application process.
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Empirical Likelihood For Change Point Detection And Estimation In Time Series ModelsPiyadi Gamage, Ramadha D. 02 August 2017 (has links)
No description available.
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How Do Java Developers Reuse StackOverflow Answers in Their GitHub Projects?Chen, Juntong 09 September 2022 (has links)
StackOverflow (SO) is a widely used question-and-answer (QandA) website for software developers and computer scientists. GitHub is a code hosting platform for collaboration and version control. Popular software libraries are open-source and published in repositories on GitHub. Preliminary observation shows developers cite SO questions in their GitHub repository. This observation inspired us to explore the relationship between SO posts and GitHub repositories; to help software developers better understand the characterization of SO answers that are reused by GitHub projects.
For this study, we conducted an empirical study to investigate the SO answers reused by Java code from public GitHub projects. We used a hybrid approach to ensure precise results: code clone detection, keyword-based search, and manual inspection. This approach helped us identify the leveraged answers from developers.
Based on the identified answers, we further investigated the topics of the discussion threads; answer characteristics (e.g., scores, ages, code lengths, and text lengths) and developers' reuse practices.
We observed both reused and unused answers. Compared with unused answers, We found that the reused answers mostly have higher scores, longer code, and longer plain text explanations. Most reused answers were related to implementing specific coding tasks. In one of our observations, 9% (40/430) of scenarios, developers entirely copied code from one or multiple answers of an SO discussion thread. Furthermore, we observed that in the other 91% (390/430) of scenarios, developers only partially reused code or created brand new code from scratch.
We investigated 130 SO discussion threads referred to by Java developers in 356 GitHub projects. We then arranged those into five different categories. Our findings can help the SO community have a better distribution of programming knowledge and skills, as well as inspire future research related to SO and GitHub. / Master of Science / StackOverflow (SO) is a widely used question-and-answer (QandA) website for software developers and computer scientists. GitHub is a code hosting platform for collaboration and version control. Popular software libraries are open-source and published in repositories on GitHub. Preliminary observation shows developers cite SO questions in their GitHub repository. This observation inspired us to explore the relationship between SO posts and GitHub repositories; to help software developers better understand the characterization of SO answers that are reused by GitHub projects. Our objectives are to guide SO answerers to help developers better; help tool builders understand how SO answers shape software products.
Thus, we conducted an empirical study to investigate the SO answers reused by Java code from public GitHub projects. We used a hybrid approach to refine our dataset and to ensure precise results. Our hybrid approach includes three steps. The first step is code clone detection. We compared two code snippets with a code clone detection tool to find the similarity. The second step is a keyword-based search. We created multiple keywords to search within GitHub code to find the referenced answers missed by step one. Lastly, we manually inspected the outputs of both step one and two to ensure zero false positives in our data. This approach helped us identify the leveraged answers from developers. Based on the identified answers, we further investigated the topics of the discussion threads, answer characteristics, and developers' reuse practices.
We observed both reused and unused answers. Compared with unused answers, We found that the reused answers mostly have higher scores, longer code, and longer plain text explanations.
Most reused answers were related to implementing specific coding tasks. In one of our observations, 9% of scenarios, developers entirely copied code from one or multiple answers of an SO discussion thread. Furthermore, we observed that in the other 91% of scenarios, developers only partially reused code or created brand new code from scratch. Our findings can help the SO community have a better distribution of programming knowledge and skills, as well as inspire future research related to SO and GitHub.
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Cassirer's philosophy of science: A neo-Kantian approach to the problem of scientific conceptsBradie, Michael Peter January 1965 (has links)
Thesis (M.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The purpose of this thesis is to present Ernst Cassirer's philosophy of science and to show its relation to Kantian philosophy. In the first chapter, the basic theme of transcendental philosophy, the concept of unity, is developed. Then, finally, the se of "transcendental" and "empirical" is explained with respect to Kant's theory of experience. Here it is pointed out that the experience is an immanent mixture of transcendental and empirical elements. Experience and self-consciousness are systematically interconnected. The transcendental concepts serving as the ground of empirical determination merely represent the inherent unity of consciousness [TRUNCATED] / 2999-01-01
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Evaluating the Potential for Estimating Age of Even-aged Loblolly Pine Stands Using Active and Passive Remote Sensing DataQuirino, Valquiria Ferraz 11 December 2014 (has links)
Data from an airborne laser scanner, a dual-band interferometric synthetic aperture radar (DBInSAR), and Landsat were evaluated for estimating ages of even-aged loblolly pine stands in Appomattox-Buckingham State Forest, Virginia, U.S.A. The DBInSAR data were acquired using the GeoSAR sensor in summer, 2008 in both the P- and X-bands. The LiDAR data were acquired in the same summer using a small-footprint laser scanner. Loblolly pine stand ages were assigned using the establishment year of loblolly pine stands provided by the Virginia Department of Forestry. Random circular plots were established in stands which varied in age from 5 to 71 years and in site index from 21 to 29 meters (base age 25 years). LiDAR- and GeoSAR-derived independent variables were calculated. The final selected LiDAR model used common logarithm of age as the dependent variable and the 99.5th percentile of height above ground as the independent variable (R2adj = 90.2%, RMSE = 4.4 years, n=45). The final selected GeoSAR models used the reciprocal of age as the dependent variable and had three independent variables: the sum of the X-band magnitude, the 25th percentile of X/P-band magnitudes, and the 90th percentile of the X-band height above ground (R2adj = 84.1%, RMSE = 7.9 years, n=46). The Vegetation Change Tracker (VCT) algorithm was run using a digital elevation layer, a land cover map, and a series of Landsat (5 and 7) images. A comparison was made between the loblolly pine stand ages obtained using the three methods and the reference data. The results show that: (1) although most of the time VCT and reference data ages were different, the differences were normally small, (2) all three remote sensing methods produced reliable age estimates, and (3) the Landsat-VCT algorithm produced the best estimates for younger stands (5 to 22 years old, RMSEVCT=2.2 years, RMSEGeoSAR=2.6 years, RMSELiDAR=2.6 years, n=35) and the model that used LiDAR-derived variables was better for older stands. Remote sensing can be used to estimate loblolly pine stand age, though prior knowledge of site index is required for active sensors that rely primarily on the relationship between age and height. / Ph. D.
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Xeditor: Inferring and Applying XML Consistency RulesWen, Chengyuan 12 1900 (has links)
XML files are frequently used by developers when building Web applications or Java EE applications. However, maintaining XML files is challenging and time-consuming because the correct usage of XML entities is always domain-specific and rarely well documented. Also, the existing compilers and program analysis tools seldom examine XML files. In this thesis, we developed a novel approach to XML file debugging called Xeditor where we extract XML consistency rules from open-source projects and use these rules to detect XML bugs. There are two phases in Xeditor: rule inference and application. To infer rules, Xeditor mines XML-based deployment descriptors in open-source projects, extracting XML entity pairs that frequently co-exist in the same files and refer to the same string literals. Xeditor then applies association rule mining to the extracted pairs. For rule application, given a program commit, Xeditor checks whether any updated XML file violates the inferred rules; if so, Xeditor reports the violation and suggests an edit for correction?. Our evaluation shows that Xeditor inferred rules with high precision (83%). For injected XML bugs, Xeditor detected rule violations and suggested changes with 74.6% precision, 50% recall. More importantly, Xeditor identified 31 really erroneous XML updates in version history, 17 of which updates were fixed by developers in later program commits. This observation implies that by using Xeditor, developers would have avoided introducing errors when writing XML files. Finally, we compared Xeditor with a baseline approach that suggests changes based on frequently co-changed entities, and found Xeditor to outperform the baseline for both rule inference and rule application. / XML files are frequently used in Java programming and when building Web application implementation. However, it is a challenge to maintain XML files since these files should follow various domain-specific rules and the existing program analysis tools seldom check XML files. In this thesis, we introduce a new approach to XML file debugging called Xeditor that extracts XML consistency rules from open-source projects and uses these rules to detect XML bugs. To extract the rules, Xeditor first looks at working XML files and finds all the pairs of entities A and B, which entities coexist in one file and have the same value on at least one occasion. Then Xeditor will check when A occurs, what is the probability that B also occurs. If the probability is high enough, Xeditor infers a rule that A is associated with B. To apply the rule, Xeditor checks XML files with errors. If a file violates the rules that were previously inferred, Xeditor will report the violation and suggest a change. Our evaluation shows that Xeditor inferred the correct rules with high precision 83%. More importantly, Xeditor identified issues in previous versions of XML files, and many of those issues were fixed by developers in later versions. Therefore, Xeditor is able to help find and fix errors when developers write their XML files.
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Empirical Analysis of User Passwords across Online ServicesWang, Chun 05 June 2018 (has links)
Leaked passwords from data breaches can pose a serious threat if users reuse or slightly modify the passwords for other services. With more and more online services getting breached today, there is still a lack of large-scale quantitative understanding of the risks of password reuse and modification. In this project, we perform the first large-scale empirical analysis of password reuse and modification patterns using a ground-truth dataset of 28.8 million users and their 61.5 million passwords in 107 services over 8 years. We find that password reuse and modification is a very common behavior (observed on 52% of the users). More surprisingly, sensitive online services such as shopping websites and email services received the most reused and modified passwords. We also observe that users would still reuse the already-leaked passwords for other online services for years after the initial data breach. Finally, to quantify the security risks, we develop a new training-based guessing algorithm. Extensive evaluations show that more than 16 million password pairs (30% of the modified passwords and all the reused passwords) can be cracked within just 10 guesses. We argue that more proactive mechanisms are needed to protect user accounts after major data breaches. / Master of Science / Since most of the internet services use text-based passwords for user authentication, the leaked passwords from data breaches pose a serious threat, especially if users reuse or slightly modify the passwords for other services. The attacker can leverage a known password from one site to guess the same user’s passwords at other sites more easily. In this project, we perform the first large-scale study of password usage based on the largest ever leaked password dataset. The dataset consists of 28.8 million users and their 61.5 million passwords from 107 internet services over 8 years. We find that password reuse and modification is a very common behavior (observed on 52% of the users). More surprisingly, we find that sensitive online services such as shopping websites and email services received the most reused and modified passwords. In addition, users would still reuse the already-leaked passwords for other online services for years after the initial data breach. Finally, we develop a cross-site password-guessing algorithm to guess the modified passwords based on one of the user’s leaked passwords. Our password guessing experiments show that 30% of the modified passwords can be cracked within only 10 guesses. Therefore, we argue that more proactive mechanisms are needed to protect user accounts after major data breaches.
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The impact of response styles on the stability of cross-national comparisonsReynolds, Nina L., Diamantopoulos, A., Simintiras, A. January 2006 (has links)
No / Response style effects are a source of bias in cross-national studies, with some nationalities being more susceptible to particular response styles than others. While response styles, by their very nature, vary with the form of the stimulus involved, previous research has not investigated whether cross-national differences in response styles are stable across different forms of a stimulus (e.g., item wording, scale type, response categories). Using a quasi-experimental design, this study shows that response style differences are not stable across different stimulus formats, and that response style effects impact on substantive cross-national comparisons in an inconsistent way.
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Empirical Essays on Social FinanceAlex Woong Bae Kim (19820298) 10 October 2024 (has links)
<p dir="ltr">In the first chapter, I explore the impact of social connections on corporate attention to climate change exposure, focusing on how these connections influence discussions during earnings calls. Using social connection data to capture the transmission of distant shocks, I find that firms in counties more socially connected to disaster areas increase their focus on climate issues compared to less connected counterparts. This heightened attention is associated with real effect, as firms with greater social ties to affected areas significantly reduce their emissions, especially indirect emissions. The findings suggest that social connections play an important role in shaping corporate attitudes towards sustainability and can drive meaningful climate actions.</p><p dir="ltr">In the second chapter, I examine how social networks influence fund managers' evaluation of the climate risks of firms. I show that fund managers tend to decrease the portfolio weights of firms that are located in disaster-affected areas to a greater degree when they have stronger social connections to those regions. This difference remains robust even when controlling for the physical distance between a fund and the disaster area. I show that such a portfolio response is primarily driven by the salience bias channel, which diminishes over time, rather than informational advantage. I do not find any similar change in the portfolio weights of firms located in the neighboring area of the disaster. Moreover, I find no significant performance difference between firms in the disaster area and those in the neighboring area in the post-disaster period.</p><p dir="ltr">In the third chapter, co-authored with M. Deniz Yavuz and Adam Reed, we report evidence that the demand for high short interest stocks by short sellers declined after the meme stock event in January 2021 due to an increased risk of short squeeze induced by the meme stock rally. We show that the positive association between high short interest and next-day borrowing cost decreased after the meme stock event. As the decline in short-selling demand varied across short interests of stocks, the demand curve in the equity lending market became steeper and inelastic after the event. Moreover, we show that this change in short-selling demand leads to higher post-event return predictability of short interest.</p>
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Inference for Cox's Regression Model via a New Version of Empirical LikelihoodJinnah, Ali 28 November 2007 (has links)
Cox Proportional Hazard Model is one of the most popular tools used in the study of Survival Analysis. Empirical Likelihood (EL) method has been used to study the Cox Proportional Hazard Model. In recent work by Qin and Jing (2001), empirical likelihood based confidence region is constructed with the assumption that the baseline hazard function is known. However, in Cox’s regression model the baseline hazard function is unspecified. In this thesis, we re-formulate empirical likelihood for the vector of regression parameters by estimating the baseline hazard function. The EL confidence regions are obtained accordingly. In addition, Adjusted Empirical Likelihood (AEL) method is proposed. Furthermore, we conduct extensive simulation studies to evaluate the performance of the proposed empirical likelihood methods in terms of coverage probabilities by comparing with the Normal Approximation based method. The simulation studies show that all the three methods produce similar coverage probabilities.
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