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Our proposed method focuses on offline friends who are acquainted with a target user in the real world. We use Density-Based Spatial Clustering of Applications with Noise (DBSCAN) to distinguish between online friends of a target user who are also offline friends and online friends who are acquainted with the target user only in cyberspace. By utilizing the probability of friendship as a function of the geographical distance between users’ home locations, our proposed method achieves an estimation accuracy 1.7 percentage point better than that of a conventional method. We have also been able to verify the effectiveness of an optimization method that narrows down candidate areas for a target user’s home location.

Purpose: The aim of this study was to determine the influence of utilization of online past examination papers on academic performance of IT students at Jomo Kenyatta University.Methodology: Descriptive survey research design was used in this study. Respondents were the 105 undergraduate students in Information Technology Department and 2 librarians in Jomo Kenyatta University of Agriculture and Technology-Eldoret Campus. They were sampled using stratified sampling, while Head of library and the library staff in charge of e-resources in JKUAT Eldoret Campus were purposively included in the study. Primary data was collected from students using closed-ended questionnaires, while interview guide was used on librarians. To ensure validity and reliability, pre-testing of research instruments was done on 20 undergraduate students of Mount Kenya university-Eldoret Campus in the department of Information Technology. D Descriptive statistics such as mean, percentage, frequencies and standard deviation, SPSS (version 22) was used in analysing data. Univariate and multiple regression analysis were used to test the hypothesis and overall model respectively. The results were presented using tables and explanations.Results: There is a positive and significant relationship between online past examination papers and academic performance of IT undergraduate students of Jomo Kenyatta University of Agriculture and Technology - Eldoret Campus. The study had a normal mean of 4.7 and standard deviation of 0.58. The online past examination papers had R estimation of 0.715. The P estimation of constant was significant (.000), consequently R square value was used. The R square estimation of 0.711 inferred that online past assessment papers anticipated 71.1% of the fluctuation in the academic performance. It had a beta of 0.504 at p

An interpretable convolutional neural network (CNN) including attribute estimation for image classification is presented in this paper. Although CNNs perform highly accurate image classification, the reason for the classification results obtained by the neural networks is not clear. In order to provide interpretation of CNNs, the proposed method estimates attributes, which explain elements of objects, in an intermediate layer of the network. This enables improvement of the interpretability of CNNs, and it is the main contribution of this paper. Furthermore, the proposed method uses the estimated attributes for image classification in order to enhance its accuracy. Consequently, the proposed method not only provides interpretation of CNNs but also realizes improvement in the performance of image classification.

The generation of waste by the paper industry has attracted great attention over the last decades among other reasons because the demand for recycled waste paper has considerably increased. As the paper industry is closely intertwined to the rest of industries in the production system, its activity exerts both a direct and indirect influence on the volume of waste generated by its supplier industries. The purpose of this study is to shed some light on the evolution of the volume of waste generated by the suppliers of the Spanish paper industry over the period 2005–2010 using an Economic Input–Output Life Cycle Assessment Model. In particular we focus on the evolution of the volume of waste generated by firms of the own paper industry. We employ data from different waste surveys conducted by the Spanish National Statistics Institute and input–output tables extracted from the World Input–Output Database. The results obtained show that the waste generated by suppliers amounted to 1250 thousand tonnes in 2010, an important volume if we take into account that the waste generated by the paper industry in 2010 amounted to 1739 thousand tonnes. The analysis of the evolution of the waste generated by suppliers reveals that there is a high degree of concentration, both in terms of industries and in terms of waste categories. In addition, the decrease in the volume of waste generated by supplier firms within the own paper industry reflects not only the growing importance of recycled paper as raw material for paper-making but also the important investments in technology made by this industry in Spain.

To review the highest impact studies published from the UK Biobank and assess their contributions to "precision medicine." We reviewed 140 of 689 studies published between 2008 and May 2019 from the UK Biobank deemed to be high impact by citations, alternative metric data, or publication in a high impact journal. We classified studies according to whether they (1) were largely methods papers, (2) largely replicated prior findings or associations, (3) generated novel findings or associations, (4) developed risk prediction models that did not yield clinically significant improvements in risk estimation over prior models or (5) developed models that produced significant improvements in individualized risk assessment, targeted screening, or targeted treatment. This final category represents "precision medicine." We classified 15 articles as category 1, 33 as category 2, 85 as category 3, six as category 4, and one as category 5. In this assessment of the first 7 years of the UK Biobank and first 4 years of genetic data availability, the majority of high impact UK Biobank studies either replicated known associations or generated novel associations without clinically relevant improvements in risk prediction, screening, or treatment. This information may be useful for designers of other cohort studies in terms of input to design and follow-up to facilitate precision medicine research.

How best to estimate the accuracy of a predictive rule has been a longstanding question in statistics. Approaches to this task range from simple methods like Mallow’s Cp to algorithmic techniques l...

OBJECTIVE To evaluate reporting of items indicative of bias and weak study design. STUDY DESIGN Literature survey. POPULATION Papers published in Veterinary Anaesthesia and Analgesia. METHODS Reporting of randomization, blinding, sample size estimation and data exclusion were compared for papers published separated by a 10 year interval. A reporting rate of more than 95% was considered ideal. The availability of data supporting results in a publicly accessible repository was also assessed. Selected papers were randomized and identifiers removed for review, with data from 59 (57 in 2009, two in 2008) and 56 (52 in 2019, four in 2018) papers analyzed. Items were categorized for completeness of reporting using a previously published operationalized checklist. Two reviewers reviewed all papers independently. RESULTS Full reporting of randomization increased over time from 13.6% to 85.7% [95% confidence interval (CI), 57.8-86.6%; p < 0.0001], as did sample size estimation (from 0% to 20%; 95% CI, 7.6-32.4%; p = 0.002). Reporting of blinding (49.2% and 50.0%; 95% CI, -18.3% to 20.0%; p = 1.0) and exclusions of samples/animals (39.0% and 50.0%; 95% CI, -8.8% to 30.8%; p = 0.3) did not change significantly. Data availability was low (2008/2009, zero papers; 2018/2019, two papers). None of the items studied exceeded the predetermined ideal reporting rate. CONCLUSIONS AND CLINICAL RELEVANCE These results indicate that reporting quality remains low, with a risk of bias.

Thermo-sensitive printers and thermo-sensitive facsimile machines are used extensively throughout China. Document examiners are often requested to confirm the authenticity of thermal paper documents. Identification of the type of thermal paper and estimation of the age of thermal paper documents could be effective methods to aid in confirming the authenticity of documents. In this paper, Fourier transform infrared (FTIR) spectrophotometry was successfully employed to differentiate between the 30 types of thermal paper. The relative age of the thermal paper documents was estimated by measuring changes in the gray value of printed strokes. The method employed resulted in curves, which indicate the relationship between the gray value of the strokes and the age of the thermal paper documents, and which are applicable for estimating the relative age of thermal paper documents in some cases. It was determined that the brand of thermal paper and thickness of strokes on the paper affected the accuracy of estimati...

This dissertation includes three chapters that cover broad topics in economics. The first chapter explores how the US Government's Capital Purchase Program, a large capital injection to local and regional banks through a stock purchase agreement, impacted local establishment dynamics such as entry, exit, employment expansion, and employment contraction following the 2008 Financial Crisis. The Capital Purchase Program dispersed over \$200 billion dollars to banks hoping to prevent failure and ease tightened lending conditions. I estimate the direct effects of a county having a bank receive Capital Purchase Program funds on local business dynamics in the seven years following treatment, as well as spillover effects as entrepreneurs and business in neighboring regions travel to gain access to credit. Estimates show the CPP had no effect on establishment entry and exit, nor employment expansion and contraction. This paper establishes that the business-lending aims of the CPP were not realized in the communities and regions that received funds, and casts further doubt on meaningful pass through of CPP funds to desirable local economic activity.The second chapter develops a joint hypothesis centered Wald test over fixed effects in large N small T panel data models with symmetric serial correlation within cross sectional observations. The enables joint hypothesis tests over inconsistently estimated fixed effects, such as the traditional varying intercept model as well as models with individual specific slope coefficients. I establish two different set of assumptions where feasible tests exist. The first assumption requires that individual errors follow a stationary $\ARp$ process. Under this assumption all second and fourth cross product moments can be consistently estimated while allowing for individual specific hypothesis and covariates to vary across individuals and time with individual specific slopes. The second feasible test requires individuals to have coefficient slopes that are shared among all individuals in a known grouping structure under the null. This set of assumptions enables estimation of a completely unconstrained variance-covariance matrix and higher cross product moments for individuals. Examples of these tests arise in wanting to establish latent panel structure, such as unobserved grouping of individuals, wanting to compare different models of teacher or firm value added against each other, or testing whether or not fixed effects can be approximated by Mundlak-Chamberlain devices.Finally, the third paper estimates how messages displaced on Dynamic Message Boards, large signs either adjacent to or displayed above roads, impact near to sign accidents. In this research, I look at the traffic-related messages such as ``drive sober,'' ``x deaths on roads this year,'' and ``click it or ticket,'' displayed on major highways, on reported near-to-sign traffic accidents. This provides estimates of the impact of different types of nudges on road safety behavior. To estimate the causal effect of these nudges, we build a new high-frequency panel data set using the information on the time and location of messages, crashes, overall traffic levels, and weather conditions using the data of the state of Vermont over a three year time period. I estimate models that control for endogeneity of displayed messages, or allow for spillover effects from neighboring messages.

We enjoyed reading Professor Efron’s (Brad) paper just as much as we enjoyed listening to his June 2019 lecture in Leiden. One of the core values underlying statistical research is in how it enable...

The new pandemic disease caused by COVID-19 virus is the crucial event over the world in the beginning of 2020. Studies on corona viruses have been however carried since several decades ago, with recent research papers published on weekly basis. We demonstrate a simple approach to explore CORD-19 dataset to provide a high level overview of important semantic changes that occurred over time. Our method aims to support better understanding of large domain-specific collections of scholarly publications that span long time periods and could be regarded as complementary to frequency-based analysis.

In this study, the role of turbulence-chemistry interaction in diesel spray auto-ignition, flame stabilization and end of injection phenomena is investigated under engine relevant “Spray A” conditions. A recently developed diesel spray combustion modeling approach, Conditional Source-term Estimation (CSE-FGM), is coupled with Reynolds-averaged Navier-Stokes simulation (RANS) framework to study the details of spray combustion. The detailed chemistry mechanism is included through the Flamelet Generated Manifold (FGM) method. Both unsteady and steady flamelet solutions are included in the manifold to account for the auto-ignition process and the subsequent flame propagation in a diesel spray. Conditionally averaged chemical source terms are closed by the conditional scalars obtained in the CSE routine. Both non-reacting and reacting spray jets are computed over a wide range of Engine Combustion Network (ECN) diesel. “Spray A” conditions. The reacting spray results are compared with simulations using a homogeneous reactor combustion model and a flamelet combustion model with the same chemical mechanism. The present study represents the first application of CSE for a diesel spray. The non-reacting liquid/vapour penetration, the mean and RMS mixture fraction, the reactive region, the flame lift-off and the ignition delay show a good agreement with literature data from an optically accessible combustion vessel over a wide range of tested conditions. The CSE-FGM model also shows a better capability in predicting the end-of-injection events in diesel spray combustion. Overall, the CSE-FGM model is shown to capture the experimental trends well, both quantitatively and qualitatively.

In this article, we discuss how we can advance our knowledge and estimation of the distribution of temperature across urban regions by going beyond the commonly known urban heat islands (UHI) phenomena, which identify the temperature difference between a city and its rural surrounding. Transit heat island (THI) focuses more on the transit routes, which are among the hottest intra-urban land covers. We also discuss new efficient and effective means of collecting data with enough spatio-temporal resolution to model and analyze THI with various smart city applications in mind.

I review my scientific career in terms of eight areas and 16 papers. The first two areas are associated with childhood. The other six are associated with residual maximum likelihood (REML), canonical transformation, inbreeding in selected populations, average information residual maximum likelihood (AIREML), the computer program ASReml and sampling-based estimation.

The production efficiency and shadow prices of three environmental outputs (BOD, COD, and SS) of 63 household-level paper-recycling units, from a recycling craft village in Vietnam, are assessed A two-stage procedure, linear programming and stochastic estimation, is used to estimate output distance function. Social capital as a production factor and environmental outputs are included in the output distance function. Results indicate that production efficiencies could potentially be improved by 28%. There is a substantial variation in the shadow prices of environmental outputs among the production units of different types of paper products. Furthermore, the average shadow prices of the three environmental outputs are all positive. This indicates a potential for improving environmental quality though introducing pollution-prevention methods to paper-recycling production processes in Vietnam (e.g., recirculation of wastewater), and suggests that it may be inappropriate to restrict the shadow prices of environmental outputs to be non-positive for the analysis of some production processes.

The data presented here are manually encoded characteristics of research papers in the area of Energy-Economy Nexus (empirical investigation of Granger causality between energy consumption and economic growth) that describe the methods, samples, and other details related to the individual estimations done in the examined empirical papers. Data cover papers indexed by Scopus, published in economic journals, written in English, after year 2000. In addition, papers were manually filtered to only those that deal with Energy-Economy Nexus investigation and have at least 10 citations at (at the time of query – November 2015). This data are to be used to conduct meta-analysis – associated dataset was used in Hajko [1] . Early version of the dataset was used for multinomial logit estimation in Master thesis by Kocianova [2] .

The purpose of this paper is to analyse the rate and the impacts of technical change in the Swedish pulp and paper industry. In contrast to earlier research on this industry we replace the standard time trend with time-specific dummy variables enabling the estimation and decomposing of a general index of technical change. The analysis is made within a Translog cost function model, which is estimated using a panel data set with observations across individual paper and board mills over the time period 1974–1994. Our results indicate that the highest rates of technical change have generally occurred during the latter part of this period. Pure technical change is the primary component that has directed technical change over the entire time period. We also find evidence of non-neutral technical change. Energy use has been stimulated by technical improvements while labour use has been discouraged. Also, technical change has had wastepaper and woodpulp using impacts. However, the magnitudes of these latter impacts are relatively small, implying that the increase in wastepaper use during the last decades has mainly been stimulated by relative price changes.