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1.
This paper evaluates the statistical methodologies of cluster analysis, discriminant analysis, and Logit analysis used in the examination of intrusion detection data. The research is based on a sample of 1200 random observations for 42 variables of the KDD-99 database, that contains ‘normal’ and ‘bad’ connections. The results indicate that Logit analysis is more effective than cluster or discriminant analysis in intrusion detection. Specifically, according to the Kappa statistic that makes full use of all the information contained in a confusion matrix, Logit analysis (K = 0.629) has been ranked first, with second discriminant analysis (K = 0.583), and third cluster analysis (K = 0.460).  相似文献   

2.
The Personalised System of Instruction is a form of mastery learning which, though it has been proven to be educationally effective, has never seriously challenged the dominant lecture-tutorial teaching method in higher education and has largely fallen into disuse. An information and communications technology assisted version of the Personalised System of Instruction using a virtual learning environment is promoted here based on the authors’ longitudinal design research into this pedagogy. The particular elements of the virtual learning environment which are promoted are short video clips, online formative tests and an assessment management system. The authors present their experiences of developing and deploying this pedagogy for the teaching of introductory discrete mathematics to large classes of Computer Science students at two UK higher education institutions both with whole cohorts and ‘at risk’ groups of students. In particular, this method is promoted as particularly helpful to students who do not adopt a deep approach to learning as many students fail to do. Moreover ‘at risk’ students using this method (n = 71) demonstrated an average Glass effect size of 0.83 compared with other ‘at risk’ students who did not (n = 35). Based on these experiences, this pedagogy is promoted as an effective approach to teaching in higher education, especially the teaching of cognitive skills to diverse cohorts of students on foundation level modules.  相似文献   

3.
Although the general public appears to have embraced the term ‘videogame addiction’, the scientific debate as to whether ‘gaming addiction’ can actually be considered an addiction similar to substance addictions of DSM-IV is still unsettled. To date, research on gaming addiction has focused on problematic behavior from the gaming activity itself and there has been little empirical research related to pathological personality patterns that usually are associated with substance addictions. Therefore, the current study examined how game exposure and ‘problematic gaming behavior’ are related to personality patterns associated with addiction by means of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). A large-scale survey study was performed among 1004 adolescent boys (age-range 11–18, M = 14.18, SD = 1.36) measuring problematic gaming behavior, physical game-related symptoms, gaming behavior and three MMPI-2 subscales measuring personality patterns usually associated with substance addiction (MAC-R, APS, AAS). Results showed that problematic gaming and physical symptoms were positively related to all MMPI-2 subscales, while game exposure was not related to the indirect measures of addictive personality patterns (i.e., MAC-R, APS). Thus, problematic gaming should be clearly distinguished from high game exposure. High game exposure merely indicates enthusiasm for some although it may be psychopathological for others.  相似文献   

4.
5.
This paper investigates a ‘grand’ educational technology innovation through theoretical lenses inspired by 10 and 11 work. Through taking this approach it is possible to show how ideas about the form of the innovation and perceptions of its ultimate ‘success’ or ‘failure’, varied between stakeholder groups. The project was pedagogically effective and popular with students, but was difficult to ‘sell’ to academics, had no senior management sponsor, and was unable to bring about cultural change in the institution despite the capital funding designed to do just that. Although many pedagogical lessons were learned, and have since been applied in other learning spaces around the host campus and elsewhere, these successful disseminations of changed practice were not in accordance with the objectives of key stakeholders. Therefore, they went unconsidered when decisions were taken about the project’s sustainability: hence the notion of ‘invisible success’. The project’s ‘failure’ is only apparent when viewed from certain perspectives; nevertheless, these perspectives are those of the powerful (or in 8 and 9 terms, those possessing capital and academic power) and are the consequence of deeply-rooted structural features in HE, which include funding models, risk-averseness, and fragmented responsibilities.  相似文献   

6.
One hundred and eleven 10th graders read an expository science text on the dipole character of water molecules (ca. 1600 words). Reading instruction was varied according to a 2 × 2 experimental design with factors ‘drawing pictures of text content on paper’ (yes, no) and ‘mentally imagining text content while reading’ (yes, no). The results indicate that drawing pictures, mediated through increased cognitive load, decreased text comprehension and, thus, learning (d = −0.37), whereas mental imagery, although decreasing cognitive load, increased comprehension only when students did not have to draw pictures simultaneously (d = 0.72). No evidence was found that the effects were moderated by domain-specific prior knowledge, verbal ability, or spatial ability. The results are in line with cognitive theories of multimedia learning, self-regulated learning, and mental imagery as well as conceptions of science learning that focus on promoting mental model construction by actively visualizing the content to be learned. Constructing mental images seems to reduce cognitive load and to increase comprehension and learning outcome when the mental visualization processes are not disturbed by externally drawing pictures on paper, whereas drawing pictures seems to increase cognitive load resulting in reduced comprehension and learning outcome.  相似文献   

7.
As Internet usage has become more prevalent among youth, so too has problematic Internet use. Despite the critical role of emotion regulation in the development of adolescents’ behaviors and the role of parenting interactions on their children’s behaviors, little research has examined these links with reference to problematic and addictive Internet use for adolescents. The main goal of this study was to examine these links, based on a sample of 525 high school students (368 males; M = 15.33 years, SD = 0.47) from a predominantly middle and lower-middle socioeconomic community in Seoul, Korea. Results from structural equation modeling revealed that students’ difficulties in emotion regulation was a mediating variable between students’ perceptions of their parents’ parenting behaviors and the students’ Internet use. The findings substantiate the importance of conceptualizing addiction from a social/cognitive theoretical framework and the notion that adolescence is the onset period for many addictive behaviors and so more proactive attention needs to be given to reducing these early negative behaviors. Based on these results, interventions designed to enhance adolescents’ emotion regulatory abilities have the likelihood to mitigate problematic and even addictive Internet use among youth.  相似文献   

8.
Contemporary social networking sites (SNSs) make idealized self-presentation and image maintenance difficult because users’ audiences are becoming more diverse and individual users must negotiate often unanticipated other-provided information in the form of text posts and digital images on their profile pages. This cross-cultural study examines how audience-related variables affect a range of strategic self-presentation and image management behaviors online. Results from samples of Singaporean and American SNS users (N = 411) show that while Americans update their profiles with text-based wall posts more frequently, Singaporeans share significantly more photos. Audience diversity is positively associated with active management of other-provided information, and females share more photos and actively manage unwanted photo tagging. Cultural identity and the tendency to ‘friend’ unknown others interact on managing other-provided wall posts; individualistic cultural identity exhibited positive relationships with these reactions for those less likely to friend unknown others but negative ones for those more likely to friend unknown others. Implications for the theoretical understanding of and practical suggestions about self-presentation online are discussed.  相似文献   

9.
This research refers to the self-regulated learning strategies proposed by Pintrich (1999) in developing a multiple-choice Web-based assessment system, the Peer-Driven Assessment Module of the Web-based Assessment and Test Analysis system (PDA-WATA). The major purpose of PDA-WATA is to facilitate learner use of self-regulatory learning behaviors to perform self-regulated learning and in turn improve e-Learning effectiveness. PDA-WATA includes five main strategies: ‘Adding Answer Notes,’ ‘Stating Confidence,’ ‘Reading Peer Answer Notes,’ ‘Recommending Peer Answer Notes’ and ‘Querying Peers’ Recommendation on Personal Answer Notes’. Using these strategies, examinees are allowed to add answer notes to explain why they chose a certain option as the correct answer and state their confidence in their own answer and answer notes, for peers’ reference. In addition to reading peer answer notes, examinees can also recommend peer answer notes as valuable references. The recommendation information can also be queried by all examinees. Quasi-experimental design was adopted to understand the effectiveness of PDA-WATA in facilitating learner use of self-regulatory learning behaviors to perform self-regulated learning and in improving learner e-Learning effectiveness. Participants were 123 seventh-grade junior high school students from four classes. These four classes were randomly divided into the PDA-WATA group (n = 63) and the N-WBT group (n = 60). Before e-Learning instruction, all students took the pre-test of the Learning Process Inventory (LPI), used to understand how often learners use self-regulatory learning behaviors in the learning process, and the pre-test of the summative assessment. After a two-week e-Learning instruction, the students all took the post-test of the LPI and the summative assessment. Results indicate that students in the PDA-WATA group appear to be more willing to take the Web-based formative assessment than students in the N-WBT group. In addition, PDA-WATA appears to be significantly more effective than N-WBT in facilitating learner use of self-regulatory learning behaviors to perform self-regulated learning and in improving their e-Learning effectiveness. Moreover, this research also finds that in the PDA-WATA group, there is no significant difference between the learning effectiveness of students with a low level of self-regulated learning and students with a high level of self-regulated learning, but similar result cannot be found in the N-WBT group.  相似文献   

10.
In this article, the effect of functional roles on group performance and collaboration during computer-supported collaborative learning (CSCL) is investigated. Especially the need for triangulating multiple methods is emphasised: Likert-scale evaluation questions, quantitative content analysis of e-mail communication and qualitative analysis of open-ended questions were used. A comparison of 41 questionnaire observations, distributed over 13 groups in two research conditions – groups with prescribed functional roles (n = 7, N = 18) and nonrole groups (n = 6, N = 23) – revealed no main effect for performance (grade). Principal axis factoring of the Likert-scales revealed a latent variable that was interpreted as perceived group efficiency (PGE). Multilevel modelling (MLM) yielded a positive marginal effect of PGE. Most groups in the role condition report a higher degree of PGE than nonrole groups. Content analysis of e-mail communication of all groups in both conditions (role n = 7, N = 25; nonrole n = 6, N = 26) revealed that students in role groups contribute more ‘coordination’ focussed statements. Finally, results from cross case matrices of student responses to open-ended questions support the observed marginal effect that most role groups report a higher degree of PGE than nonrole groups.  相似文献   

11.
In this study, teachers' acceptance and use of an educational portal is assessed based on data from two sources: usage data (number of logins, downloads, uploads, reactions and pages viewed) and an online acceptance questionnaire. The usage data is extracted on two occasions from the portal's database: at survey completion (T1) and twenty-two months later (T2). Framework for this study is C-TAM-TPB (Combined Technology Acceptance Model and Theory of Planned Behavior). 919 usable responses from teachers are obtained. Based on the observed use data at T1, four types of portal users are distinguished: ‘new’ (N = 37), ‘light’ (N = 641), ‘medium’ (N = 201), and ‘heavy’ (N = 40). Path analyses show that all predictor variables in C-TAM-TPB influence teachers' portal acceptance, but their significance level varies depending on the user type. The strongest predictors of behavioral intention to use the portal are attitude (‘new’) and perceived usefulness (‘light’, ‘medium’ and ‘heavy’), with variance explained ranging from .39 (‘medium’) to .71 (‘heavy’). The observed use data show that the portal is primarily used to search for and download material, rather than for sharing material or information. The use data at T2 show that teachers become more efficient in their search behavior and that the majority of the teachers use the portal more frequently. Guidelines are proposed to policymakers and school boards aiming to introduce a similar technology to teachers.  相似文献   

12.
The study examined how the reduced nonverbal cues characteristic of computer-mediated communication (CMC) moderated the potentially negative interpersonal outcomes of social anxiety in initial interactions. Hypotheses predicted that CMC would mitigate the extent to which social anxiety caused interpersonal perceptions of anxiety and that CMC would attenuate the negative association between one’s social anxiety and one’s partner’s conversational satisfaction. A sample (N = 206) of undergraduate students were paired in unacquainted dyads and then engaged in initial interaction conversations in either a face-to-face (FtF) or CMC context. The researchers measured social anxiety before the conversation and a number of outcomes after the conversation. The results revealed that CMC is a significant contingent condition to the association between social anxiety and one’s partner’s perception of this anxiety and a contingent condition to the association between social anxiety and one’s partner’s conversational satisfaction.  相似文献   

13.

Introduction

A usability test was employed to evaluate two medical software applications at an expert conference setting. One software application is a medical diagnostic tool (electrocardiogram [ECG] viewer) and the other is a medical research tool (electrode misplacement simulator [EMS]). These novel applications have yet to be adopted by the healthcare domain, thus, (1) we wanted to determine the potential user acceptance of these applications and (2) we wanted to determine the feasibility of evaluating medical diagnostic and medical research software at a conference setting as opposed to the conventional laboratory setting.

Methods

The medical diagnostic tool (ECG viewer) was evaluated using seven delegates and the medical research tool (EMS) was evaluated using 17 delegates that were recruited at the 2010 International Conference on Computing in Cardiology. Each delegate/participant was required to use the software and undertake a set of predefined tasks during the session breaks at the conference. User interactions with the software were recorded using screen-recording software. The ‘think-aloud’ protocol was also used to elicit verbal feedback from the participants whilst they attempted the pre-defined tasks. Before and after each session, participants completed a pre-test and a post-test questionnaire respectively.

Results

The average duration of a usability session at the conference was 34.69 min (SD = 10.28). However, taking into account that 10 min was dedicated to the pre-test and post-test questionnaires, the average time dedication to user interaction of the medical software was 24.69 min (SD = 10.28). Given we have shown that usability data can be collected at conferences, this paper details the advantages of conference-based usability studies over the laboratory-based approach. For example, given delegates gather at one geographical location, a conference-based usability evaluation facilitates recruitment of a convenient sample of international subject experts. This would otherwise be very expensive to arrange. A conference-based approach also allows for data to be collected over a few days as opposed to months by avoiding administration duties normally involved in laboratory based approach, e.g. mailing invitation letters as part of a recruitment campaign.Following analysis of the user video recordings, 41 (previously unknown) use errors were identified in the advanced ECG viewer and 29 were identified in the EMS application. All use errors were given a consensus severity rating from two independent usability experts. Out of a rating scale of 4 (where 1 = cosmetic and 4 = critical), the average severity rating for the ECG viewer was 2.24 (SD = 1.09) and the average severity rating for the EMS application was 2.34 (SD = 0.97). We were also able to extract task completion rates and times from the video recordings to determine the effectiveness of the software applications. For example, six out of seven tasks were completed by all participants when using both applications. This statistic alone suggests both applications already have a high degree of usability. As well as extracting data from the video recordings, we were also able to extract data from the questionnaires. Using a semantic differential scale (where 1 = poor and 5 = excellent), delegates highly rated the ‘responsiveness’, ‘usefulness’, ‘learnability’ and the ‘look and feel’ of both applications.

Conclusion

This study has shown the potential user acceptance and user-friendliness of the novel EMS and the ECG viewer applications within the healthcare domain. It has also shown that both medical diagnostic software and medical research software can be evaluated for their usability at an expert conference setting. The primary advantage of a conference-based usability evaluation over a laboratory-based evaluation is the high concentration of experts at one location, which is convenient, less time consuming and less expensive.  相似文献   

14.
This study examines the effects of illness (cancer and Parkinson’s [PD]) on three moderators, the expression of positive and negative emotions and cognitive mechanisms. Each illness makes its own unique demands on patients and may influence change mechanisms. Similarly, we are asking, what effects do the type of leadership have on mediators that have previously been linked to positive outcomes. Four types of groups were studied, professional, the wellness community (TWC) chat mixed cancer (N groups = 4) and TWC chat PD patient groups (N groups = 6). The two peer groups were bulletin boards for colorectal cancer (N groups = 1) and PD BBs (N groups = 6). The design was a 2×2, disease and leader type. Computer-based text analysis, the linguistic inquiry and word count assessed the dependent variables. The results of the Manova found that; disease is P = NS, leader type, P = .00, interaction, P = .00. The interaction between disease and leader type is statistically significant, indicating that disease in combination with whether the leader is a peer or professional effects the expression of emotions and cognitive mechanisms.  相似文献   

15.
Studies have shown that multitasking with technology, specifically using Social Networking Sites (SNSs), decreases both efficiency and productivity in an academic setting. This study investigates multitasking’s impact on the relationship between SNS use and Grade Point Average (GPA) in United States (US; n = 451) and European (n = 406) university students using quantitative and qualitative data analysis. Moderated Multiple Regression analysis results showed that the negative relationship between SNS use and GPA was moderated by multitasking only in the US sample. This may be due to European students being less prone to “disruptive” multitasking. The results provide valuable cautionary information about the impact of multitasking and using SNSs in a learning environment on university students’ GPAs.  相似文献   

16.
Forest structure data derived from lidar is being used in forest science and management for inventory analysis, biomass estimation, and wildlife habitat analysis. Regression analysis dominated previous approaches to the derivation of tree stem and crown parameters from lidar. The regression model for tree parameters is locally applied based on vertical lidar point density, the tree species involved, and stand structure in the specific research area. The results of this approach, therefore, are location-specific, limiting its applicability to other areas. For a more widely applicable approach to derive tree parameters, we developed an innovative method called ‘wrapped surface reconstruction’ that employs radial basis functions and an isosurface. Utilizing computer graphics, we capture the exact shape of an irregular tree crown of various tree species based on the lidar point cloud and visualize their exact crown formation in three-dimensional space. To validate the tree parameters given by our wrapped surface approach, survey-grade equipment (a total station) was used to measure the crown shape. Four vantage points were established for each of 55 trees to capture whole-tree crown profiles georeferenced with post-processed differential GPS points. The observed tree profiles were linearly interpolated to estimate crown volume. These fieldwork-generated profiles were compared with the wrapped surface to assess goodness of fit. For coniferous trees, the following tree crown parameters derived by the wrapped surface method were highly correlated (< 0.05) with the total station-derived measurements: tree height (R2 = 0.95), crown width (R2 = 0.80), live crown base (R2 = 0.92), height of the lowest branch (R2 = 0.72), and crown volume (R2 = 0.84). For deciduous trees, wrapped surface-derived parameters of tree height (R2 = 0.96), crown width (R2 = 0.75), live crown base (R2 = 0.53), height of the lowest branch (R2 = 0.51), and crown volume (R2 = 0.89) were correlated with the total station-derived measurements. The wrapped surface technique is less susceptible to errors in estimation of tree parameters because of exact interpolation using the radial basis functions. The effect of diminished energy return causes the low correlation for lowest branches in deciduous trees (R2 = 0.51), even though leaf-off lidar data was used. The wrapped surface provides fast and automated detection of micro-scale tree parameters for specific applications in areas such as tree physiology, fire modeling, and forest inventory.  相似文献   

17.
In this paper, we consider Blackwell’s Theorem in which inter-arrival times are characterized as fuzzy variables under t-norm-based fuzzy operations. We first prove that Blackwell’s Theorem for T-related fuzzy variables with respect to necessity measure holds true where T is an Archimedean t-norm. Subsequently, we provide a counter example under which Blackwell’s Theorem does not hold when T = min. Finally, we evaluate the expected value of fuzzy variable with respect to credibility measure and derive fuzzy Blackwell’s Theorem based on the expected value of fuzzy variables.  相似文献   

18.
Computer- and web-based testing procedures are increasingly popular for the assessment of cognitive abilities and knowledge. This paper identified color red as a critical context factor that may influence the results. Two studies showed that color red may harm the performance in web-based tests of general knowledge. In Study 1 (N = 131) a red (vs. green) progress bar impeded the performance in a knowledge test, but only for the male participants. In Study 2 (N = 190) the color of the survey’s forward-button was manipulated (red vs. blue vs. mixed color) which led to a replication of the gender-dependent color effect. Evolutionary psychology and stereotype threat research explain why red impedes the activation of knowledge among men, but not among women.  相似文献   

19.
We explore the ability to enhance landscape fire detection and characterization by constructing a ‘virtual’ fire product from a synthesis of geostationary and polar orbiting satellite data. Active fire pixels detected by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) and the Moderate Resolution Imaging Spectroradiometer (MODIS) were spatially and temporally collated across Africa between February 2004 and January 2005. Coincident fire pixels detected by SEVIRI and MODIS were used to populate an empirical database of frequency density (f-D) distributions of fire radiative power (FRP). Frequency density distributions of FRP measured by SEVIRI at 5.0° grid cell resolution and 15-minute temporal resolution were then cross referenced in the database to a set of counterpart f-D distributions of FRP measured by MODIS. This procedure resulted in the first generation of a ‘virtual’ fire product that exhibits the full continental coverage and high temporal resolution of SEVIRI whilst quantifying fire pixel counts and FRP with accuracies approaching those of MODIS. Diurnal cycles extracted from the virtual fire product indicate that SEVIRI measures a greater proportion of the active fire pixels and FRP potentially detectable by MODIS during the day due to the increased prevalence and stronger radiant contribution of highly energetic fire pixels. On a daily basis (sample size n = 365) the peak magnitude in the diurnal cycle of the virtual FRP occurred within the same 15-minute timeslot as in the native SEVIRI fire product. Continental-scale ignition and extinction events, however, were detected on average 44 min earlier (standard deviation s.d. = 40 min) and 137 min later (s.d. = 92 min), respectively. It is anticipated that the methodology developed here can be used to cross-calibrate active fire products between a variety of different satellite platforms.  相似文献   

20.
Near real-time data from the MODIS satellite sensor was used to detect and trace a harmful algal bloom (HAB), or red tide, in SW Florida coastal waters from October to December 2004. MODIS fluorescence line height (FLH in W m− 2 μm− 1 sr− 1) data showed the highest correlation with near-concurrent in situ chlorophyll-a concentration (Chl in mg m− 3). For Chl ranging between 0.4 to 4 mg m− 3 the ratio between MODIS FLH and in situ Chl is about 0.1 W m− 2 μm− 1 sr− 1 per mg m− 3 chlorophyll (Chl = 1.255 (FLH × 10)0.86, r = 0.92, n = 77). In contrast, the band-ratio chlorophyll product of either MODIS or SeaWiFS in this complex coastal environment provided false information. Errors in the satellite Chl data can be both negative and positive (3-15 times higher than in situ Chl) and these data are often inconsistent either spatially or temporally, due to interferences of other water constituents. The red tide that formed from November to December 2004 off SW Florida was revealed by MODIS FLH imagery, and was confirmed by field sampling to contain medium (104 to 105 cells L− 1) to high (> 105 cells L− 1) concentrations of the toxic dinoflagellate Karenia brevis. The FLH imagery also showed that the bloom started in mid-October south of Charlotte Harbor, and that it developed and moved to the south and southwest in the subsequent weeks. Despite some artifacts in the data and uncertainty caused by factors such as unknown fluorescence efficiency, our results show that the MODIS FLH data provide an unprecedented tool for research and managers to study and monitor algal blooms in coastal environments.  相似文献   

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