Stacked bar charts are a visualization method for presenting multiple attributes of data,and many visualization tools support these charts.To assess the efficacy of stacked bar charts in supporting attributecomparison...Stacked bar charts are a visualization method for presenting multiple attributes of data,and many visualization tools support these charts.To assess the efficacy of stacked bar charts in supporting attributecomparison tasks,we conducted a user study to compare three types of stacked bar charts:classical,inverting,and diverging.Each chart type was used to visualize six attributes of data where half of the attributes have the characteristics of‘lower better’whereas the other half attributes are with‘higher better.’Thirty participants were asked to perform two types of comparison tasks:single-attribute and overall-attribute comparisons.We measured the completion time,error rate,and perceived difficulty of the comparison tasks.The results of the study suggest that,for overall-attribute comparisons,the inverting stacked bar chart was the most effective with regards to the completion time.The results also show that performing overall-attribute comparisons using the classical and diverging stacked bar charts required more time than performing single-attribute comparisons using these charts.Participants perceived the inverting and diverging stacked bar charts as easier-to-use than the classical stacked bar chart for overall-attribute comparisons.However,for single-attribute comparisons,all chart types delivered similar performance.We discuss how these findings can inform the better design of interactive stacked bar charts and visualization tools.展开更多
This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points...This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points (OCP), upper control limit UCLx, and zonal demarcations. Multi-rules were used to identify the number of out-of-control-points, Nocp as violations using five control chart rules applied separately. A sensitivity analysis on the Nocp was applied for subgroup size, k, and number of sigma above the mean value to determine the upper control limit, UCLx. A computer code was implemented using a FORTRAN code to create x-bar control-charts and capture OCP and other control-chart characteristics with increasing k from 2 to 25. For each value of k, a complete series of average values, Q(p), of specific length, Nsg, was created from which statistical analysis was conducted and compared to the original SIF data, S(t). The variation of number of out-of-control points or violations, Nocp, for different control-charts rules with increasing k was determined to follow a decaying exponential function, Nocp = Ae–α, for which, the goodness of fit was established, and the R2 value approached unity for Rule #4 and #5 only. The goodness of fit was established to be the new criteria for rational subgroup-size range, for Rules #5 and #4 only, which involve a count of 6 consecutive points decreasing and 8 consecutive points above the selected control limit (σ/3 above the grand mean), respectively. Using this criterion, the rational subgroup range was established to be 4 ≤ k ≤ 20 for the two x-bar control chart rules.展开更多
针对输出质量特性服从正态分布的随机偏移单部件可修系统,研究了可变样本容量和控制线(Variable Sampling Size and Control Limits,VSSCL)均值控制图和预防维修策略联合经济设计问题。首先,构建了VSSCL均值控制图和预防维修策略联合经...针对输出质量特性服从正态分布的随机偏移单部件可修系统,研究了可变样本容量和控制线(Variable Sampling Size and Control Limits,VSSCL)均值控制图和预防维修策略联合经济设计问题。首先,构建了VSSCL均值控制图和预防维修策略联合经济设计的集成框架,揭示控制图和预防维修策略运行的耦合机制;然后,基于VSSCL均值控制图和系统状态特征参数,针对给出的集成框架确定了可能形成系统更新的四个维修事件的发生概率,并进一步利用更新过程理论和全概率公式,建立了VSSCL均值控制图和预防维修策略联合经济设计的平均单位时间成本最小决策模型;同时,针对具体实例,将构建的联合设计决策模型和独立设计决策模型进行比较分析,结果表明联合设计决策模型具有明显的经济优势;最后,利用回归正交试验设计方法对模型参数的灵敏度进行了分析。展开更多
评估平均值—极差值质控图(X-Bar and R Charts)在临床检验室内质控中的应用价值。利用SPSS质控程序中的平均值—极差值质控图分析甘油三酯的模拟质控数据,生成X-Bar(平均值)和R(极差值)质控图,并产生多种能力指数和性能指数。平均值—...评估平均值—极差值质控图(X-Bar and R Charts)在临床检验室内质控中的应用价值。利用SPSS质控程序中的平均值—极差值质控图分析甘油三酯的模拟质控数据,生成X-Bar(平均值)和R(极差值)质控图,并产生多种能力指数和性能指数。平均值—极差值质控图正确显示了违反质控规则的质控点,并对此做出了详细的报告;能力指数和性能指数正确反映了质控过程维持在规格限内的能力。平均值—极差值质控图适合于分析临床检验定量项目的质控数据。展开更多
基金Lee Howorko received funding from MacEwan University,Canada through the Undergraduate Student Research Initiative Grant.
文摘Stacked bar charts are a visualization method for presenting multiple attributes of data,and many visualization tools support these charts.To assess the efficacy of stacked bar charts in supporting attributecomparison tasks,we conducted a user study to compare three types of stacked bar charts:classical,inverting,and diverging.Each chart type was used to visualize six attributes of data where half of the attributes have the characteristics of‘lower better’whereas the other half attributes are with‘higher better.’Thirty participants were asked to perform two types of comparison tasks:single-attribute and overall-attribute comparisons.We measured the completion time,error rate,and perceived difficulty of the comparison tasks.The results of the study suggest that,for overall-attribute comparisons,the inverting stacked bar chart was the most effective with regards to the completion time.The results also show that performing overall-attribute comparisons using the classical and diverging stacked bar charts required more time than performing single-attribute comparisons using these charts.Participants perceived the inverting and diverging stacked bar charts as easier-to-use than the classical stacked bar chart for overall-attribute comparisons.However,for single-attribute comparisons,all chart types delivered similar performance.We discuss how these findings can inform the better design of interactive stacked bar charts and visualization tools.
文摘This paper analyzes the effect of subgroup size on the x-bar chart characteristics using sample influx (SIF) into forensic science laboratory (FSL). The characteristics studied include changes in out-or-control points (OCP), upper control limit UCLx, and zonal demarcations. Multi-rules were used to identify the number of out-of-control-points, Nocp as violations using five control chart rules applied separately. A sensitivity analysis on the Nocp was applied for subgroup size, k, and number of sigma above the mean value to determine the upper control limit, UCLx. A computer code was implemented using a FORTRAN code to create x-bar control-charts and capture OCP and other control-chart characteristics with increasing k from 2 to 25. For each value of k, a complete series of average values, Q(p), of specific length, Nsg, was created from which statistical analysis was conducted and compared to the original SIF data, S(t). The variation of number of out-of-control points or violations, Nocp, for different control-charts rules with increasing k was determined to follow a decaying exponential function, Nocp = Ae–α, for which, the goodness of fit was established, and the R2 value approached unity for Rule #4 and #5 only. The goodness of fit was established to be the new criteria for rational subgroup-size range, for Rules #5 and #4 only, which involve a count of 6 consecutive points decreasing and 8 consecutive points above the selected control limit (σ/3 above the grand mean), respectively. Using this criterion, the rational subgroup range was established to be 4 ≤ k ≤ 20 for the two x-bar control chart rules.
文摘针对输出质量特性服从正态分布的随机偏移单部件可修系统,研究了可变样本容量和控制线(Variable Sampling Size and Control Limits,VSSCL)均值控制图和预防维修策略联合经济设计问题。首先,构建了VSSCL均值控制图和预防维修策略联合经济设计的集成框架,揭示控制图和预防维修策略运行的耦合机制;然后,基于VSSCL均值控制图和系统状态特征参数,针对给出的集成框架确定了可能形成系统更新的四个维修事件的发生概率,并进一步利用更新过程理论和全概率公式,建立了VSSCL均值控制图和预防维修策略联合经济设计的平均单位时间成本最小决策模型;同时,针对具体实例,将构建的联合设计决策模型和独立设计决策模型进行比较分析,结果表明联合设计决策模型具有明显的经济优势;最后,利用回归正交试验设计方法对模型参数的灵敏度进行了分析。
文摘评估平均值—极差值质控图(X-Bar and R Charts)在临床检验室内质控中的应用价值。利用SPSS质控程序中的平均值—极差值质控图分析甘油三酯的模拟质控数据,生成X-Bar(平均值)和R(极差值)质控图,并产生多种能力指数和性能指数。平均值—极差值质控图正确显示了违反质控规则的质控点,并对此做出了详细的报告;能力指数和性能指数正确反映了质控过程维持在规格限内的能力。平均值—极差值质控图适合于分析临床检验定量项目的质控数据。
