Estimation

估计
  • 文章类型: Journal Article
    背景:COVID-19大流行促使美国卫生与人类服务部发起了“COVID-19公众教育运动”,以提高成年人对疫苗的信心和吸收,因为疫苗是预防严重疾病和死亡的关键。
    目的:过去与COVID-19行为相关的细分研究发现了态度上的重要差异,社会人口统计学,以及随后在不同人群中的COVID-19预防行为。这项研究通过纳入更全面的态度来扩展先前的工作,行为,和社会人口统计学变量,通过不同水平的COVID-19疫苗信心来识别人群,并评估他们随后吸收COVID-19预防行为的差异。
    方法:数据来自基于网络的纵向的5波(2021年1月至2022年6月),以英语和西班牙语进行的基于概率的美国成年人小组调查(N=4398)。参与者是从芝加哥大学国家AmeriSpeak小组的NORC招募的,并被邀请参加多次浪潮。潜在类别聚类分析基于40多种COVID-19态度估计的受访者细分,信仰,行为,和第1波中报道的社会人口统计学。调查加权交叉表格和双变量回归分析评估了COVID-19疫苗摄取的差异,助推器摄取,面罩使用,以及所有5次调查浪潮中所有细分领域的社交距离。
    结果:总共6个部分(强硬派非有意者,符合预防规定的非故意者,被烧死的服务员,焦虑的服务员,持怀疑态度的密友,和准备好的密友)被确认,这与他们对COVID-19疫苗的信心不同,与预防相关的态度和行为,和社会人口统计学。交叉表格和回归结果表明,COVID-19疫苗和加强时机存在显著的部门成员差异,面罩使用,和社交距离。调查加权交叉表比较了各段COVID-19疫苗和加强剂摄取的结果表明,这些结果在6个段之间存在统计学上的显著差异(P<.001)。每个部分的结果均具有统计学意义(精疲力尽的服务员中的助推器摄取P<0.01;所有其他系数P<0.001),表明,平均而言,疫苗接种意愿较低的细分市场的受访者报告说,与已准备好的密友接种疫苗和加强剂的时间相比,COVID-19疫苗和加强剂的接收时间较晚。
    结论:结果通过显示与COVID-19疫苗接种相关的初始信念和行为,扩展了以前的研究,面罩使用,和社会距离对于理解随后对推荐的COVID-19预防措施的依从性差异很重要。具体来说,我们发现,在受访者群体中,接种疫苗和加强疫苗的概率与COVID-19疫苗信心和面罩使用以及社交距离依从性相对应;在疫苗信心水平相似的情况下,更合规的部分比不合规的部分更有可能接种疫苗或加强疫苗接种.这些发现有助于确定活动的适当受众。结果突出了使用全面的态度清单,行为,以及其他个体水平的特征,这些特征可以作为未来与COVID-19和其他传染病相关的细分工作的基础。
    BACKGROUND: The COVID-19 pandemic prompted the launch of the US Department of Health and Human Services\' COVID-19 Public Education Campaign to boost vaccine confidence and uptake among adults, as vaccines are key to preventing severe illness and death.
    OBJECTIVE: Past segmentation research relevant to COVID-19 behavior has found important differences in attitudes, sociodemographics, and subsequent COVID-19 prevention behaviors across population segments. This study extends prior work by incorporating a more comprehensive set of attitudes, behaviors, and sociodemographic variables to identify population segments by differing levels of COVID-19 vaccine confidence and evaluate differences in their subsequent uptake of COVID-19 prevention behaviors.
    METHODS: Data were obtained from 5 waves (January 2021 to June 2022) of a web-based longitudinal, probability-based panel survey of US adults (N=4398) administered in English and in Spanish. Participants were recruited from NORC at the University of Chicago\'s national AmeriSpeak panel and were invited to participate across multiple waves. Latent class cluster analysis estimated segments of respondents based on over 40 COVID-19 attitudes, beliefs, behaviors, and sociodemographics as reported in wave 1. Survey-weighted cross-tabulations and bivariate regression analyses assessed differences in COVID-19 vaccine uptake, booster uptake, mask use, and social distancing in all segments across all 5 survey waves.
    RESULTS: A total of 6 segments (hardline nonintenders, prevention-compliant nonintenders, burned-out waiters, anxious waiters, skeptical confidents, and ready confidents) were identified, which differed by their COVID-19 vaccine confidence, prevention-related attitudes and behaviors, and sociodemographics. Cross-tabulations and regression results indicated significant segment membership differences in COVID-19 vaccine and booster timing, mask use, and social distancing. Results from survey-weighted cross-tabulations comparing COVID-19 vaccine and booster uptake across segments indicate statistically significant differences in these outcomes across the 6 segments (P<.001). Results were statistically significant for each segment (P<.01 for booster uptake among burned-out waiters; P<.001 for all other coefficients), indicating that, on average, respondents in segments with lower intentions to vaccinate reported later receipt of COVID-19 vaccines and boosters relative to the timing of vaccine and booster uptake among ready confidents.
    CONCLUSIONS: Results extend previous research by showing that initial beliefs and behaviors relevant to COVID-19 vaccination, mask use, and social distancing are important for understanding differences in subsequent compliance with recommended COVID-19 prevention measures. Specifically, we found that across respondent segments, the probability of vaccine and booster uptake corresponded with both COVID-19 vaccine confidence and mask use and social distancing compliance; more compliant segments were more likely to get vaccinated or boosted than less compliant segments given similar levels of vaccine confidence. These findings help identify appropriate audiences for campaigns. Results highlight the use of a comprehensive list of attitudes, behaviors, and other individual-level characteristics that can serve as a basis for future segmentation efforts relevant to COVID-19 and other infectious diseases.
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  • 文章类型: Journal Article
    背景:本研究旨在调查与算术任务中的跨文化差异相关的认知和情感因素。
    方法:从中国和意大利招募了404名三年级和四年级学生来完成精确的算术运算,算术估计和认知任务(即,短期记忆,执行功能,和流体推理)。他们的数学焦虑也被测量。
    结果:结果显示,中国儿童在算术任务和轮班任务中的表现均优于意大利儿童。意大利儿童在视觉空间更新任务中表现更好,数学焦虑水平高于中国同龄人。多组路径分析显示,认知因素之间的关系模式(即,短期记忆,抑制和移位),数学焦虑,各组的算术性能相似。唯一的例外是,视觉空间更新唯一地预测了中国人的算术估计,而不是意大利儿童的算术估计。
    结论:中国儿童在精确算术任务中的表现优于意大利同龄人,可能是由于在中国数学教育中更加强调算术流畅性,在学校和家里。在算术估计任务中,他们也比意大利同行略有优势。在中国儿童而不是意大利儿童中发现的更新和算术估计之间的独特联系表明,尽管在这两个国家的课程中都没有强调算术估计,精确算术的指导和练习可以提高中国儿童解决算术估计问题的效率。
    BACKGROUND: This study aimed to investigate the cognitive and affective factors associated with cross-cultural differences in arithmetic tasks.
    METHODS: A total of 404 third- and fourth- graders were recruited from China and Italy to complete exact arithmetic, arithmetic estimation and cognitive tasks (i.e., short-term memory, executive functions, and fluid reasoning). Their mathematical anxiety was also measured.
    RESULTS: The results showed that Chinese children performed better than Italian children in both arithmetic tasks and in shifting task. Italian children performed better in visuospatial updating task and reported higher levels of mathematical anxiety than their Chinese peers. Multi-group path analyses showed that the patterns of relations among cognitive factors (i.e., short-term memory, inhibition and shifting), mathematical anxiety, and arithmetic performance were similar across groups. The only exception was that visuospatial updating uniquely predicted arithmetic estimation for Chinese but not for Italian children.
    CONCLUSIONS: Chinese children outperformed their Italian peers in the exact arithmetic task, likely due to the greater emphasis on arithmetic fluency in Chinese mathematics education, both in schools and at home. They also had a slight advantage than Italian peers in the arithmetic estimation task. The unique link between updating and arithmetic estimation found in Chinese children but not Italian children suggests that, although arithmetic estimation is not emphasized in the curricula of either country, instruction and practice in exact arithmetic may enhance Chinese children\'s efficiency in solving arithmetic estimation problems.
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  • 文章类型: Letter
    暂无摘要。
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  • 文章类型: Journal Article
    目标:不良的唤醒管理可能导致认知表现下降。指定模型和解码器来推断认知唤醒和表现有助于通过音乐等非侵入性致动器进行唤醒调节。方法:我们在期望最大化框架内采用贝叶斯过滤方法,在存在平静和令人兴奋的音乐的情况下,在[公式:见文本]-返回任务期间跟踪隐藏状态。我们从皮肤电导和行为信号中解码唤醒和表现状态,分别。我们基于Yerkes-Dodson定律推导了唤醒性能模型。通过考虑相应的性能和皮肤电导作为观察,我们设计了基于性能的唤醒解码器。结果:给出了量化的唤醒和表现。可以从唤醒-表现关系来解释Yerkes-Dodson定律的存在。研究结果显示在令人兴奋的音乐中表现出更高的矩阵。结论:基于性能的唤醒解码器与Yerkes-Dodson定律具有更好的一致性。我们的研究可以在设计非侵入性闭环系统中实施。
    Goal: Poor arousal management may lead to reduced cognitive performance. Specifying a model and decoder to infer the cognitive arousal and performance contributes to arousal regulation via non-invasive actuators such as music. Methods: We employ a Bayesian filtering approach within an expectation-maximization framework to track the hidden states during the [Formula: see text]-back task in the presence of calming and exciting music. We decode the arousal and performance states from the skin conductance and behavioral signals, respectively. We derive an arousal-performance model based on the Yerkes-Dodson law. We design a performance-based arousal decoder by considering the corresponding performance and skin conductance as the observation. Results: The quantified arousal and performance are presented. The existence of Yerkes-Dodson law can be interpreted from the arousal-performance relationship. Findings display higher matrices of performance within the exciting music. Conclusions: The performance-based arousal decoder has a better agreement with the Yerkes-Dodson law. Our study can be implemented in designing non-invasive closed-loop systems.
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  • 文章类型: Journal Article
    本文研究了一种新的概率分布类别以及该类别中的特定成员。通过利用从基分布的分布函数得出的比值比,我们已经制定了一个新的三角分布族。这个新设计的分布家族被称为“正弦派幂奇数G家族”,是通过涉及正弦函数的变换构造的。本文概述了该提议的分布族固有的基本特征。使用威布尔分布作为基本参考,我们介绍了一个属于拟议分配家族的成员。该成员展示了各种危险函数,如j,reverse-j,增加,递减,或浴缸形状。本文研究了这种新引入的分布的基本统计属性。分布参数的估计是通过最大似然估计方法进行的。通过蒙特卡罗模拟验证了参数估计程序的准确性。这些模拟的结果表明,随着样本量的增加,偏差和均方误差减少,即使是小样本。考虑了两组实际工程数据来证明所提出的分布的适用性。使用一些模型选择标准和拟合优度检验统计来评估建议分布的性能。这些评估的经验证据证明,所提出的模型优于六个现有模型。
    This paper investigates a novel category of probability distributions and a specific member within this category. We have formulated a new family of trigonometric distributions by utilizing the odds ratio derived from the distribution function of a base distribution. This newly devised distribution family termed the \"Sine pie-power odd-G family\" of distributions, is constructed through a transformation involving the sine function. The paper presents an overview of the fundamental characteristics inherent to this proposed distribution family. Using the Weibull distribution as a base reference, we have introduced a member belonging to the proposed distribution family. This member demonstrates various hazard functions such as j, reverse-j, increasing, decreasing, or bathtub shapes. The paper examines essential statistical attributes of this newly introduced distribution. The estimation of the distribution\'s parameters is carried out via the maximum likelihood estimation method. The accuracy of the parameter estimation procedure is validated through Monte Carlo simulations. The outcomes of these simulations reveal a reduction in biases and mean square errors as sample sizes increase, even for small samples. Two sets of real-engineering data are considered to demonstrate the proposed distribution\'s applicability. The performance of the suggested distribution is evaluated using some model selection criteria and goodness-of-fit test statistics. Empirical evidence from these evaluations substantiates that the proposed model outperforms six existing models.
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  • 文章类型: Journal Article
    许多现实的系统发育模型缺乏可处理的似然函数,禁止使用标准推断方法。我们呈现phyddle,基于管道的工具包,用于使用无似然深度学习方法执行系统发育建模任务。通过五个分析步骤(Simulate,格式,火车,估计,和图)将原始系统发育数据集作为输入转换为基于数值和可视化模型的输出。基准测试表明,phyddle可以准确地执行一系列推理任务,比如估计宏观进化参数,在连续性状进化模型中选择,通过流行病学模型的覆盖测试,即使对于缺乏可处理的可能性的模型也是如此。phyddle具有灵活的命令行界面,使系统发生的深度学习方法易于集成到研究工作流程中。了解有关phyddle的更多信息,请访问https://phyddle.org。
    Many realistic phylogenetic models lack tractable likelihood functions, prohibiting their use with standard inference methods. We present phyddle, a pipeline-based toolkit for performing phylogenetic modeling tasks using likelihood-free deep learning approaches. phyddle coordinates modeling tasks through five analysis steps (Simulate, Format, Train, Estimate, and Plot) that transform raw phylogenetic datasets as input into numerical and visualized model-based output. Benchmarks show that phyddle accurately performs a range of inference tasks, such as estimating macroevolutionary parameters, selecting among continuous trait evolution models, and passing coverage tests for epidemiological models, even for models that lack tractable likelihoods. phyddle has a flexible command-line interface, making it easy to integrate deep learning approaches for phylogenetics into research workflows. Learn more about phyddle at https://phyddle.org.
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  • 文章类型: Journal Article
    使用传统记录技术测量奶牛甲烷(CH4)排放是复杂且昂贵的。预测模型,根据代理信息估算CH4排放量,提供一个可访问的替代方案。这篇综述涵盖了预测奶牛CH4排放量所采用的不同建模方法,并强调了它们各自的优势和局限性。遵循系统评价和荟萃分析的首选报告项目(PRISMA);Scopus,EBSCO,WebofScience,PubMed和PubAg分别被查询标题包含与“牛,“统计分析或机器学习的暴露”,“和“甲烷排放”的结果。搜索于2022年12月执行,没有设置发布日期范围。符合条件的论文是通过统计或机器学习方法研究奶牛中CH4排放预测的论文,并以英文提供。最初的搜索返回了299篇论文,其中55、有资格参加讨论。来自55篇论文的数据是通过探索的CH4排放预测方法合成的,包括机械建模,实证建模,机器学习(ML)发现机械模型非常准确,然而他们需要难以获得输入数据,which,如果不精确,会产生误导性的结果。相比之下,经验模型仍然更通用,然而,当应用于其原始发育范围之外时,却遭受了巨大的痛苦。对商业奶牛场CH4排放量的预测可以利用任何方法,然而,他们使用的特征必须在商业农场环境中是可获得的。牛奶脂肪酸(MFA)似乎是研究中最受欢迎的商业可获得性状,然而,基于MFA的模型产生了矛盾的结果,应在实现可靠的准确性之前进行合并。ML模型通过各种先进算法为预测奶牛CH4排放提供了一种新颖的方法,并且可以通过混合或堆叠技术促进异构数据类型的组合。除此之外,它们还提供了通过插补策略提高数据集复杂性的能力。这些机会使机器学习模型能够解决传统预测方法面临的局限性,以及加强对商业农场的预测。
    Measuring dairy cattle methane (CH4) emissions using traditional recording technologies is complicated and expensive. Prediction models, which estimate CH4 emissions based on proxy information, provide an accessible alternative. This review covers the different modeling approaches taken in the prediction of dairy cattle CH4 emissions and highlights their individual strengths and limitations. Following the guidelines set out by the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA); Scopus, EBSCO, Web of Science, PubMed and PubAg were each queried for papers with titles that contained search terms related to a population of \"Bovine,\" exposure of \"Statistical Analysis or Machine Learning,\" and outcome of \"Methane Emissions\". The search was executed in December 2022 with no publication date range set. Eligible papers were those that investigated the prediction of CH4 emissions in dairy cattle via statistical or machine learning (ML) methods and were available in English. 299 papers were returned from the initial search, 55 of which, were eligible for inclusion in the discussion. Data from the 55 papers was synthesized by the CH4 emission prediction approach explored, including mechanistic modeling, empirical modeling, and machine learning. Mechanistic models were found to be highly accurate, yet they require difficult-to-obtain input data, which, if imprecise, can produce misleading results. Empirical models remain more versatile by comparison, yet suffer greatly when applied outside of their original developmental range. The prediction of CH4 emissions on commercial dairy farms can utilize any approach, however, the traits they use must be procurable in a commercial farm setting. Milk fatty acids (MFA) appear to be the most popular commercially accessible trait under investigation, however, MFA-based models have produced ambivalent results and should be consolidated before robust accuracies can be achieved. ML models provide a novel methodology for the prediction of dairy cattle CH4 emissions through a diverse range of advanced algorithms, and can facilitate the combination of heterogenous data types via hybridization or stacking techniques. In addition to this, they also offer the ability to improve dataset complexity through imputation strategies. These opportunities allow ML models to address the limitations faced by traditional prediction approaches, as well as enhance prediction on commercial farms.
    This review provides a comprehensive overview of the different modeling approaches taken in the prediction of dairy cattle methane emissions. Mechanistic models, which mathematically simulate the methane production process of the dairy cattle rumen, are both accurate and adaptable, yet their necessary input data is difficult to obtain and if imprecise, can produce misinformative results. Empirical models, which statistically quantify the relationships between methane emissions and production factors, are a more accessible alternative to mechanistic models, yet their accessible structure limits them to the same range of data on which they were originally developed. Machine learning models, which are based on a particular learning pattern, can be trained to identify trends in methane production and use these lessons to make accurate predictions. Their application in the prediction of dairy cattle methane emissions remains scarce, yet those that have been show promising potential. Commercially deployable models can utilize any of the previous approaches, as long as the traits they use are obtainable in a commercial farm setting. Those developed favor the use of milk fatty acids, yet the variation in their results needs to be consolidated before robust predictions of methane emissions on commercial farms can be achieved.
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  • 文章类型: Journal Article
    已知身高是由复杂的多基因因素控制的经典遗传性状。到目前为止,已经在整个基因组中发现了许多与身高相关的遗传变异。它也是用于预测法医学外观的外部可见特征(EVC)的代表。当犯罪现场的生物证据不足以识别个人时,可以考虑使用某些遗传变异对法医DNA表型进行检查.在这项研究中,我们的目标是预测\'高度\',代表性的法医表型,当短串联重复序列(STR)分析在生物样品不足的情况下很困难时,使用少量的遗传变异。我们的结果不仅复制了以前的遗传信号,而且还表明,随着两种性别的验证和复制阶段的高度增加,多基因评分(PGS)呈上升趋势。这些结果表明,本研究中建立的SNP集可用于韩国人群的身高估计。具体来说,由于本研究中构建的PGS模型仅针对少量SNP,即使在犯罪现场,它也有助于以最少的生物学证据进行法医DNA表型鉴定。据我们所知,这是第一项利用GWAS信号评估韩国人群身高估测PGS模型的研究.我们的研究提供了对东亚人身高的多基因效应的见解,纳入非亚洲人群的遗传变异。
    Height is known to be a classically heritable trait controlled by complex polygenic factors. Numerous height-associated genetic variants across the genome have been identified so far. It is also a representative of externally visible characteristics (EVC) for predicting appearance in forensic science. When biological evidence at a crime scene is deficient in identifying an individual, the examination of forensic DNA phenotyping using some genetic variants could be considered. In this study, we aimed to predict \'height\', a representative forensic phenotype, by using a small number of genetic variants when short tandem repeat (STR) analysis is hard with insufficient biological samples. Our results not only replicated previous genetic signals but also indicated an upward trend in polygenic score (PGS) with increasing height in the validation and replication stages for both genders. These results demonstrate that the established SNP sets in this study could be used for height estimation in the Korean population. Specifically, since the PGS model constructed in this study targets only a small number of SNPs, it contributes to enabling forensic DNA phenotyping even at crime scenes with a minimal amount of biological evidence. To the best of our knowledge, this was the first study to evaluate a PGS model for height estimation in the Korean population using GWAS signals. Our study offers insight into the polygenic effect of height in East Asians, incorporating genetic variants from non-Asian populations.
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  • 文章类型: Journal Article
    ICHE9(R1)中概述的评估框架描述了在临床试验中精确定义要估计的效果所需的组件。其中包括如何处理基线后“间流”事件(IE)。在后期临床试验中,通常使用治疗政策策略处理“治疗中止”等IE,并将治疗效果作为结局的目标,无论治疗中止与否.对于连续重复的措施,这种类型的影响通常使用停药前后的所有观察到的数据进行估计,使用重复测量混合模型(MMRM)或多重归因(MI)处理任何缺失数据.在基本形式上,这两种估计方法在分析中都忽略了治疗中止,因此,如果治疗中止后的患者与仍被分配治疗的患者相比存在差异,则可能存在偏见。和丢失的数据更常见的患者谁已经停止治疗。因此,我们提出并评估了一组MI模型,可以适应治疗中止前后结果之间的差异。这些模型是在规划呼吸道疾病的3期试验的背景下进行评估的。我们表明,忽略治疗中止的分析可能会引入实质性偏差,有时可能会低估变异性。我们还表明,提出的一些MI模型可以成功地纠正偏差,但不可避免地导致方差的增加。我们得出的结论是,一些提出的MI模型比忽略治疗中断的传统分析更可取,但是MI模型的精确选择可能取决于试验设计,治疗中止后的关注疾病以及观察到的和缺失的数据量。
    The estimands framework outlined in ICH E9 (R1) describes the components needed to precisely define the effects to be estimated in clinical trials, which includes how post-baseline \'intercurrent\' events (IEs) are to be handled. In late-stage clinical trials, it is common to handle IEs like \'treatment discontinuation\' using the treatment policy strategy and target the treatment effect on outcomes regardless of treatment discontinuation. For continuous repeated measures, this type of effect is often estimated using all observed data before and after discontinuation using either a mixed model for repeated measures (MMRM) or multiple imputation (MI) to handle any missing data. In basic form, both these estimation methods ignore treatment discontinuation in the analysis and therefore may be biased if there are differences in patient outcomes after treatment discontinuation compared with patients still assigned to treatment, and missing data being more common for patients who have discontinued treatment. We therefore propose and evaluate a set of MI models that can accommodate differences between outcomes before and after treatment discontinuation. The models are evaluated in the context of planning a Phase 3 trial for a respiratory disease. We show that analyses ignoring treatment discontinuation can introduce substantial bias and can sometimes underestimate variability. We also show that some of the MI models proposed can successfully correct the bias, but inevitably lead to increases in variance. We conclude that some of the proposed MI models are preferable to the traditional analysis ignoring treatment discontinuation, but the precise choice of MI model will likely depend on the trial design, disease of interest and amount of observed and missing data following treatment discontinuation.
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  • 文章类型: Journal Article
    现代科学依赖于纳米尺度的成像,通常通过检测由高度聚焦的入射带电粒子束产生的二次电子的过程来实现。多种类型的测量噪声限制了图像质量和入射粒子剂量之间的最终权衡。这可能会妨碍剂量敏感样品的有用成像。现有的改善图像质量的方法不能从根本上减轻噪声源。此外,分配物理上有意义的尺度的障碍使图像定性。这里,我们介绍了离子计数辅助显微镜(ICAM),这是一种定量成像技术,使用统计原理估计的二次电子产量。随着数据收集的容易实现的变化,ICAM大大降低了源散粒噪声。在氦离子显微镜中,我们证明了3[公式:参见文本]剂量减少以及这些经验结果与理论性能预测之间的良好匹配。ICAM促进易碎样品的成像,并且可以使具有较重颗粒的成像更具吸引力。
    Modern science is dependent on imaging on the nanoscale, often achieved through processes that detect secondary electrons created by a highly focused incident charged particle beam. Multiple types of measurement noise limit the ultimate trade-off between the image quality and the incident particle dose, which can preclude useful imaging of dose-sensitive samples. Existing methods to improve image quality do not fundamentally mitigate the noise sources. Furthermore, barriers to assigning a physically meaningful scale make the images qualitative. Here, we introduce ion count-aided microscopy (ICAM), which is a quantitative imaging technique that uses statistically principled estimation of the secondary electron yield. With a readily implemented change in data collection, ICAM substantially reduces source shot noise. In helium ion microscopy, we demonstrate 3[Formula: see text] dose reduction and a good match between these empirical results and theoretical performance predictions. ICAM facilitates imaging of fragile samples and may make imaging with heavier particles more attractive.
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