Chart Users Research Articles

Reconceptualizing Cross-Cutting Political Expression on Social Media: A Case Study of Facebook Comments During the 2016 Brexit Referendum

ABSTRACT Political communication research has long sought to understand the effects of cross-cutting exposure on political participation. Here, we argue for a paradigm shift that acknowledges the agency of citizens as producers of cross-cutting expression on social media. We define cross-cutting expression as political communication through speech or behavior within a counter-attitudinal space. After explicating our conceptualization of cross-cutting expression, we empirically explore: its extent, its relationship to political arguments, and its implications for digital campaigning during the 2016 Brexit Referendum. Our dataset, comprising 2,198,741 comments from 344,884 users, is built from Facebook comments to three public campaign pages active during the Brexit referendum: StrongerIn, VoteLeave, and LeaveEU. We utilize reactions data to sort partisans into “Remain” and “Brexit” camps and, thereafter, chart users’ commenting flows across the three pages. We estimate 29% of comments to be cross-cutting, and we find strong correlations between cross-cutting expression and reasoned political arguments. Then, to better understand how cross-cutting expression may influence political participation on social media, we topic model the dataset to identify the political themes discussed during the Brexit debate on Facebook. Our findings suggest that political Facebook pages are not echo chambers, that cross-cutting expression correlates with reasoned political arguments, and that cross-cutting expression may influence the online voter mobilization potential of political Facebook pages.

Causal Support: Modeling Causal Inferences with Visualizations.

Analysts often make visual causal inferences about possible data-generating models. However, visual analytics (VA) software tends to leave these models implicit in the mind of the analyst, which casts doubt on the statistical validity of informal visual "insights". We formally evaluate the quality of causal inferences from visualizations by adopting causal support-a Bayesian cognition model that learns the probability of alternative causal explanations given some data-as a normative benchmark for causal inferences. We contribute two experiments assessing how well crowdworkers can detect (1) a treatment effect and (2) a confounding relationship. We find that chart users' causal inferences tend to be insensitive to sample size such that they deviate from our normative benchmark. While interactively cross-filtering data in visualizations can improve sensitivity, on average users do not perform reliably better with common visualizations than they do with textual contingency tables. These experiments demonstrate the utility of causal support as an evaluation framework for inferences in VA and point to opportunities to make analysts' mental models more explicit in VA software.

Visual Reasoning Strategies for Effect Size Judgments and Decisions.

Uncertainty visualizations often emphasize point estimates to support magnitude estimates or decisions through visual comparison. However, when design choices emphasize means, users may overlook uncertainty information and misinterpret visual distance as a proxy for effect size. We present findings from a mixed design experiment on Mechanical Turk which tests eight uncertainty visualization designs: 95% containment intervals, hypothetical outcome plots, densities, and quantile dotplots, each with and without means added. We find that adding means to uncertainty visualizations has small biasing effects on both magnitude estimation and decision-making, consistent with discounting uncertainty. We also see that visualization designs that support the least biased effect size estimation do not support the best decision-making, suggesting that a chart user's sense of effect size may not necessarily be identical when they use the same information for different tasks. In a qualitative analysis of users' strategy descriptions, we find that many users switch strategies and do not employ an optimal strategy when one exists. Uncertainty visualizations which are optimally designed in theory may not be the most effective in practice because of the ways that users satisfice with heuristics, suggesting opportunities to better understand visualization effectiveness by modeling sets of potential strategies.

Unconditional performance of the X¯ chart: Comparison among five standard deviation estimators

AbstractTo design the control chart, the in‐control process mean and standard deviation must be estimated from historical samples, negatively affecting the chart's performance. The grand mean of a sample is the well‐established estimator for the process mean. However, regarding the standard deviation, the chart's user has at least five different estimators available in the literature to choose from. In this paper, using intensive simulations, we study and compare the performance of the chart (under normality assumption and three‐sigma limits) among the most five used standard deviation estimators. The unconditional in‐control run length (RL0) is the most commonly used performance measure of a control chart, and many authors base their comparisons on the expectation of the RL0 or on the mean square error of the estimators. In contrast, we based our comparison on the proportions of the RL0 concentrated at some intervals that are usually considered undesired by the practitioner due to the high incidence of false alarms during the process monitoring (e.g., RL0 between 1 and 200), occurring earlier than expected when compared with known parameter situations. From our results, all the studied standard deviation estimators generate similar performances. However, even with this similarity, we showed that one of the most recommended standard deviation estimators in the literature in control charts with estimated parameters may be the most inappropriate choice based on the undesired RL0 proportions.

Development of a Computer Aided Beam Deflection Analysis (CABDA) Program for Simply Supported Loaded Beams

Beam-like members such as shafts, levers, frame components, beam structures, etc. are regularly designed and constructed in the field of mechanical and civil engineering. It is pertinent to know the structural integrity of the design before construction or fabrication. Beam deflection and stress calculations can be cumbersome and results from commercial simulation packages are not devoid of truncation and/or round-off errors because they are based on numerical schemes. To reduce or eliminate these issues, a computational tool, CABDA, has been designed and developed on matlab. The algorithm is based on analytic equations of beam deflection and bending stress theories; a design flow chart and graphic user interface were done to implement the algorithm. Experiments and simulations have been carried out for steel and brass rectangular beams which were compared with results obtained from CABDA for the same beam model. Average deflection errors recorded for steel beam are-0.4 and-0.015; for brass beam are-0.69 and-0.1 for experiment and simulation respectively. Average bending stress error recorded is-0.19 for simulation. It is observable that simulation results compare closely but CABDA gives exact results and therefore is very appropriate for simple beam problems.

Efektivitas Penggunaan Kartu Menuju Sehat Lansia di Posyandu Lansia Wilayah Kerja Puskesmas Cepiring Kabupaten Kendal

The health services for Elderly-Integrated Health Post (IHP) include physical and emotional mental health checks that are recorded and monitored with Elderly-Growth Chart. This study aims to know the efectiveness of the use of Elderly-Growth Chart. This was qualitative research. Data collected by in-depth interviews, used interview guidelines, to the elderly-Growth Chart users, the main informants were elderly IHP health workers and triangulation informant were elderly ad elderly families. The results showed that the use of elderly-Growth Chart was not efective because since 2013 elderly-Growth Chart had not been used anymore because Elderly-Growth Chart were often lost and not taken during the elderly-IHP, tables in forms that were too small that cause diiculty to write and read and there was an additional workload on health workers to do the recording, because there were 3 reports that must be made. The recomendation is developing the recording system of health examination result of elderly IHP to help health workers, elderly and elderly families to monitor, and do early detection diseases and improve the elderly health Keywords: elderly, elderly IHP, elderly growth chart

Run length quantiles of EWMA control charts monitoring normal mean or/and variance

Exponentially weighted moving average (EWMA) control charts are well-established devices for monitoring process stability. Typically, control charts are evaluated by considering their Average Run Length (ARL), that is the expected number of observations or samples until the chart signals. Because of the limitations of an average, various papers also dealt with the run length distribution and quantiles. Going beyond these papers, we develop algorithms for and evaluate the quantile performance of EWMA control charts with variance adjusted control limits and with fast initial response features, of EWMA charts based on the sample variance, and of EWMA charts simultaneously monitoring mean and variance. Additionally, for the mean charts we consider medium, late and very late process changes and their impact on appropriately conditioned run length quantiles. It is demonstrated that considering run length quantiles can protect from constructing distorted EWMA designs while optimising their zero-state ARL performance. The implementation of all the considered measures in the R package ‘spc’ allows any control chart user to consider EWMA schemes from the run length quantile prospective in an easy way.

A Nonparametric Phase I Control Chart for Individual Observations Based on Empirical Likelihood Ratio

One common challenge in nonmanufacturing control chart applications is that many of the nonmanufacturing quality characteristics are not normally distributed. In these applications, normal transformation of the observations is certainly feasible; however, it will be done at the expense of the interpretability of the analysis that is particularly important to control chart users in nonmanufacturing industries.Most of the existing nonparametric control charts are designed for Phase II monitoring. Little has been done in developing nonparametric Phase I control charts especially for individual observations that are prevalent in nonmanufacturing applications. In this work, we propose a new nonparametric Phase I control chart for monitoring the location parameter whose construction is essentially based on the empirical likelihood ratio test. The performance of the proposed chart, in terms of the signal probability, compares favorably with the recently developed charts for individual observations. A nonmanufacturing example is included in which the proposed chart and the other competing charts are applied and compared. Copyright © 2014 John Wiley & Sons, Ltd.

Semiotic evaluation of Lithuania military air navigation charts

Abstract Research of semiotic aspects Lithuanian military air navigation charts was based on the semantic, graphic and information load analysis. The aim of semantic analysis was to determine how the conventional cartographical symbols, used in air navigation charts, correspond with carto-linguistic and carto-semiotic requirements. The analysis of all the markings was performed complex and collected by questionnaire were interviewed various respondents: pilots, cartographers and other chart users. The researches seek two aims: evaluate information and graphical load of military air navigation charts. Information load evaluated to calculate all objects and phenomenon, which was in 25 cm² of map. Charts analysis showed that in low flight charts (LFC) average information load are 4 - 5 times richer than in the operational maps. Map signs optimization on LFC has to be managed very carefully, choosing signs that can reduce the load of information and helps for the information transfer process. Graphical load of maps evaluated of aeronautical maps is not great (5 - 12%) and does not require reduction the information load and generalization of charts. Air navigation charts analysis pointed that not all air navigation sings correspond carto-semiotic requirements and must be improved. The authors suggested some new sings for military air navigation chart, which are simpler, equivalent to human psychophysical perception criteria, creates faster communication and less load on the chart.

An Economic Approach to the Management of High-Quality Processes

Modern manufacturing developments have forced researchers to investigate alternative quality control techniques for high-quality processes. The cumulative count of conforming (CCC) control chart is a powerful alternative approach for monitoring high-quality processes for which traditional control charts are inadequate. This study develops a mathematical model for the economic design of the CCC control chart and presents an application of the proposed model. On the basis of the results of the application, the economic and classical CCC control chart designs of the CCC control chart are compared. The optimal design parameters for different defective fractions are tabulated, and a sensitivity analysis of the model is presented for the CCC control chart user to determine the optimal economic design parameters and minimum hourly costs for one production run according to different defective fractions, cost, time, and process parameters. Copyright © 2012 John Wiley & Sons, Ltd.

Designing observation charts to optimize the detection of patient deterioriation: Reliance on the subjective preferences of healthcare professionals is not enough

Observation charts are critical to detecting patient deterioration. Research suggests their design has a dramatic impact on user performance in terms of failure rates for detecting abnormal vital signs and how quickly users can interpret recorded observations. In this study, we examined the design preferences of professional chart users to assess their alignment with objective performance data. In addition, we tested the assumptions of prior knowledge that chart designers appear to have made about chart users. We conducted an online survey of health professionals (n=347). Participants answered questions about their observation chart design preferences in general, and were randomly assigned to evaluate one of nine specific charts. Chart users' preferences for design features were not always consistent with objective performance data. While some views concurred with empirical findings (e.g., participants preferred to plot observations on a graph with graded colouring, where the colours corresponded with degrees of abnormality), others did not (e.g., participants preferred plotting blood pressure and pulse together on the same chart area, which the objective data suggest is problematic). Additionally, a substantial proportion of respondents were unfamiliar with some of the assumed knowledge required to interpret many charts (e.g., particular abbreviations). It is dangerous to rely solely on subjective opinions - even those of experienced health professionals - when developing patient observation charts, as optimal design may be counterintuitive and some preferences may merely reflect familiarity. Objective performance data is also required. In addition, the level of assumed knowledge required to use a chart should be minimized.

Supporting the detection of patient deterioration: Observation chart design affects the recognition of abnormal vital signs

AimTo evaluate the effect of observation chart design on the ability of health professionals and novice chart users to recognise patient deterioration. MethodsParticipants were 45 health professionals (doctors and nurses) and 46 novices. Each participant completed 48 trials in which they viewed realistic patient observations recorded on six hospital observation charts of differing design quality. Each chart design was used on eight trials, four times with normal data and four times with abnormal data. On each trial, the participant's task was to identify any abnormal observation or else to indicate that all observations were normal (based on normal physiological ranges given in the instructions). The main outcome measures were participants’ error rates and response times for detecting abnormal observations on each of the six charts. ResultsThere was a significant effect of chart type on error rates (p<0.001), but health professionals made the same number of errors as novices (p=0.43). Chart type also had a significant effect on response times (p<0.001). Health professionals responded faster overall than novices (p=0.006); however, a significant interaction between chart type and participant group (p=0.02) indicated that the health professionals’ advantage was confined to the two most rudimentary charts. No significant differences were found between doctors and nurses on either measure. ConclusionsOur findings suggest that observation chart design has a substantial impact on the decision accuracy and response times of both health professionals and novices in recognising abnormal patient observations.

A new control chart based on the loess smooth applied to information system quality performance

Sometimes to measure the performance of an information system, unusually long response times of database operation need to be identified. Compared with Lloyd’s (1995) statistical process control chart, we propose an outlier resistant robust locally weighted scatterplot smooth (loess) based control chart that identifies effectively all the out of control points of operation in Lloyd’s (1995) data. Our findings provide guidance to management in information system quality control and more generally to all control chart users in cases where outliers occur in the charted data.

한국 해도 번호체계 개선 방안에 관한 연구

Now Korea Hydrographic and Oceanographic Administration(KHOA) publishes 309 charts of 38 kinds of scale. Korea chart index number system is established with east, south and west sea areas. The chart number has been given irregularly in accordance with publication order so there is no consistence. The present chart index number system can classify sea areas but does not have information of scale, object and location. Therefore this chart`s unsystematic management gives rise to inconvenience to the chart user. So, the standards of chart index number system is urgently needed for the efficient management & use of chart. In this paper, we intend to propose new chart index number system through adjusting area of chart and rearranging scale of charts. As a result, it is necessary to change from 3 digits to 4 digits index number to gain competitiveness & systematic management of Korea nautical charts.

Economic statistical design of a T2 control chart with double warning lines

AbstractRecent studies have shown that enhancing the common T2 control chart by using variable sample sizes (VSS) and variable sample intervals (VSI) sampling policies with a double warning line scheme (DWL) yields improvements in shift detection times over either pure VSI or VSS schemes in detecting almost all shifts in the process mean. In this paper, we look at this problem from an economical perspective, certainly at least as an important criterion as shift detection time if one considers what occurs in the industry today. Our method is to first construct a cost model to find the economic statistical design (ESD) of the DWL T2 control chart using the general model of Lorenzen and Vance (Technometrics 1986; 28:3–11). Subsequently, we find the values of the chart parameters which minimize the cost model using a genetic algorithm optimization method. Cost comparisons of Fixed ratio sampling, VSI, VSS, VSIVSS with DWL, and multivariate exponentially weighted moving average (MEWMA) charts are made, which indicate the economic efficacy of using either VSIVSS with DWL or MEWMA charts in practice if cost minimization is of interest to the control chart user. Copyright © 2010 John Wiley &amp; Sons, Ltd.

Detecting improvement using Shewhart attribute control charts when the lower control limit is zero

In this paper, we present a method to monitor count data so as to be able to detect improvement when the counts are low enough to cause the lower limit to be zero. The method, which is proposed as an add-on to the conventional Shewhart control chart, consists in counting the number of samples in which zero defectives or zero defects per unit occur and signaling an increase in quality if k-in-a-row or 2-in-t samples have zero counts of defectives or zero defects per unit. This method enjoys some similarities to the very popular Shewhart control chart in that it is easy to design, understand and use. It is flexible, robust, and, like the Shewhart chart, yields detection frequencies that are optimal for very large shifts and good for other shifts. Some comparisons with traditional CUSUM charts are provided. Figures enabling Shewhart control chart users to easily design low-side add-on control charts are given for c and np charts.

Fast initial response features for EWMA control charts

The exponentially weighted moving average (EWMA) control chart became very popular during the last decade. It is characterized by simple handling and good performance. It turns out, however, that the most popular EWMA scheme with fixed-width control limits—the asymptotic control limits are taken and do not change over time—detects early changes rather slowly. For the competing CUSUM chart the so-called fast initial response (head-start) feature is developed which permits rapid response to an initial out-of-control situation. Meanwhile, in some papers similar modifications for EWMA schemes are described. We compare these approaches by using precise computation techniques, which are based on numeric quadrature rules and allow higher accuracy than earlier studies. Moreover, previous comparisons are restricted to the evaluation of the detection speed by comparing the average run lengths (ARLs), that is, the parameter of interest is constant during the whole monitoring period. Here, we consider more possible change point locations, which gives the EWMA control chart user a better insight into the scheme performance for early changes. *** DIRECT SUPPORT *** A00T7005 00004

Two bivariate geometrically defined reference regions with applications to male reproductive hormones and human growth.

Two conceptually simple two-dimensional reference charts are described. The charts are characterized analytically, but also by geometric properties that are easily communicated to subject-matter researchers--the users of such charts. For both charts, the proposed estimators are non-parametric, so no distributional assumptions are needed about the two-dimensional response. An important example that will serve to motivate and illustrate one of the charts is the study of the human reproductive hormones Inhibin B and FSH. A low Inhibin B concentration combined with a high FSH concentration is an indication that something may be wrong in the seminal cells which produce semen, and such measurements help in the process of distinguishing between different reasons for infertility. The aim in the study of the human reproductive hormones was to give a two-dimensional reference curve for the non-normally distributed hormone measurements while taking into account that some measurements were left-censored because of a detection limit in the assay used to measure the concentrations.

ARL Comparisons Between Neural Network Models and -Control Charts for Quality Characteristics that are Nonnormally Distributed

One widely used control chart, the -chart, is based on the assumption that means of samples drawn from the process are normally distributed. When the normality assumption is not valid, control chart users may choose from several different courses of action. These include using Box-Cox power transformations on the original data to yield an approximate normal distribution, increasing the size of the samples drawn from the process until the distribution of the sample means is considered normal, and modifying the -chart to employ asymmetric control limits instead of limits that are equidistant from the process target mean. Since none of the remedies for handling nonnormal processes is completely satisfactory, we build on previous neural network research by developing a neural network to control nonnormal processes. Comparison of the performance of our neural network model with that of traditional -control charts shows that the neural network model is superior to the traditional -control charts.

Improvement Detection by Control Charts for High Yield Processes

Introduction Statistical process (SPC) is by now a commonly used quality assurance tool. One of the most important SPC techniques is the use of charts for maintaining process performance; their effectiveness lies in their ability to alert users of any deterioration of process behaviour so that potential damage can be alleviated or averted in time. As a result, the attention of chart users, mostly technical personnel, is normally focused on process deterioration. From a management point of view, the ability to detect process improvements in the form of of control states is no less important, since improvements can take place as a result of process stabilization or learning effects. In this article we address this subject with reference to a conventional process chart and its application in a high yield or low defective manufacturing environment, and offer some practical implementation procedures. Many manufacturing processes today have attained quality levels far higher than those commonly found when Shewhart charts were first proposed in the 1920s[1]. One of such charts, namely np-chart for the of nonconforming items (defectives), faces some implementation problems when the proportion nonconforming p is low and the size of each sample n is not large enough. In particular, based on 3ơ deviation from process mean, the lower limit (LCL) is often below zero which has no physical meaning. It is often advised in textbooks or journal papers that this LCL be ignored or zero be taken instead as the lower limit. However, such practice contradicts the fundamental idea of SPC by charts. A process is judged out of when it, with a certain probability, performs worse than expected; in such a case action should be taken to make the necessary corrections to the process. The process may also be out-of-control in the sense that it has become better than expected; in such a situation useful information can be sought about how the new-found quality improvement may be sustained. This is an extremely valuable opportunity not be missed, as continuous improvement is now the cornerstone of modern quality management.