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Point-light and full-view short video clips of female walkers were displayed on a CRT monitor and male students rated the likelihood of selecting a walker for various advances. Relationships between the ratings, the walkers’ self-reported frequencies of being approached, gait cues, and self-rated personality traits were examined. In the point-light condition, raters selected slow walkers with a short stride length and personality traits implying vulnerability as targets for inappropriate touching. In the full-view condition, the raters selected fashionably groomed or physically attractive walkers as sexual advance targets. These criteria corresponded partially with reported occurrences of advances. Awkward movement impression was suggested as a kinematic gait quality influencing sexual advance target choice. 相似文献
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Group sequential monitoring based on the weighted log‐rank test statistic with the Fleming–Harrington class of weights in cancer vaccine studies
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Takahiro Hasegawa 《Pharmaceutical statistics》2016,15(5):412-419
In recent years, immunological science has evolved, and cancer vaccines are now approved and available for treating existing cancers. Because cancer vaccines require time to elicit an immune response, a delayed treatment effect is expected and is actually observed in drug approval studies. Accordingly, we propose the evaluation of survival endpoints by weighted log‐rank tests with the Fleming–Harrington class of weights. We consider group sequential monitoring, which allows early efficacy stopping, and determine a semiparametric information fraction for the Fleming–Harrington family of weights, which is necessary for the error spending function. Moreover, we give a flexible survival model in cancer vaccine studies that considers not only the delayed treatment effect but also the long‐term survivors. In a Monte Carlo simulation study, we illustrate that when the primary analysis is a weighted log‐rank test emphasizing the late differences, the proposed information fraction can be a useful alternative to the surrogate information fraction, which is proportional to the number of events. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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本文用声发射法分析了塑性加工界面摩擦润滑状态。得到了金属拉拔时,声发射事件总数与拉拔速度,断面收缩率,润滑油粘度之间的关系。从声发射参数的变化,可看出界面状态变化的情况。因此,用声发射法可对塑性加工界面上的摩擦润滑状态的变化,进行动态下实时监测,进而可为产品的加工质量监控,提供新的方法。 相似文献
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Takahiro Hasegawa Saori Misawa Shintaro Nakagawa Shinichi Tanaka Takanori Tanase Hiroyuki Ugai Akira Wakana Yasuhide Yodo Satoru Tsuchiya Hideki Suganami 《Pharmaceutical statistics》2020,19(4):436-453
Many clinical research studies evaluate a time‐to‐event outcome, illustrate survival functions, and conventionally report estimated hazard ratios to express the magnitude of the treatment effect when comparing between groups. However, it may not be straightforward to interpret the hazard ratio clinically and statistically when the proportional hazards assumption is invalid. In some recent papers published in clinical journals, the use of restricted mean survival time (RMST) or τ ‐year mean survival time is discussed as one of the alternative summary measures for the time‐to‐event outcome. The RMST is defined as the expected value of time to event limited to a specific time point corresponding to the area under the survival curve up to the specific time point. This article summarizes the necessary information to conduct statistical analysis using the RMST, including the definition and statistical properties of the RMST, adjusted analysis methods, sample size calculation, information fraction for the RMST difference, and clinical and statistical meaning and interpretation. Additionally, we discuss how to set the specific time point to define the RMST from two main points of view. We also provide developed SAS codes to determine the sample size required to detect an expected RMST difference with appropriate power and reconstruct individual survival data to estimate an RMST reference value from a reported survival curve. 相似文献
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Jouchi Nakajima Tsuyoshi Kunihama Yasuhiro Omori 《Journal of applied statistics》2017,44(7):1248-1268
This paper develops Bayesian inference of extreme value models with a flexible time-dependent latent structure. The generalized extreme value distribution is utilized to incorporate state variables that follow an autoregressive moving average (ARMA) process with Gumbel-distributed innovations. The time-dependent extreme value distribution is combined with heavy-tailed error terms. An efficient Markov chain Monte Carlo algorithm is proposed using a state-space representation with a finite mixture of normal distributions to approximate the Gumbel distribution. The methodology is illustrated by simulated data and two different sets of real data. Monthly minima of daily returns of stock price index, and monthly maxima of hourly electricity demand are fit to the proposed model and used for model comparison. Estimation results show the usefulness of the proposed model and methodology, and provide evidence that the latent autoregressive process and heavy-tailed errors play an important role to describe the monthly series of minimum stock returns and maximum electricity demand. 相似文献
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Hikaru Hasegawa 《Australian & New Zealand Journal of Statistics》1998,40(2):171-180
There exist many studies which treat the inequality and/or interval constraints on coefficients in the homoscedastic linear regression model. However, the sampling performance of the inequality constrained estimators in the heteroscedastic linear model has not been examined. This paper considers the inequality constrained estimators in the heteroscedastic linear regression model and derives their risks under a quadratic loss function. Furthermore, using the inequality constrained estimators, we introduce a pre-test estimator which might be employed after the test for homoscedasticity and derive its risk. In addition, the risk performance of these estimators is evaluated numerically. 相似文献
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I Nyoman Widiarta Tsuyoshi Ikeda Kenji Fujisaki Fusao Nakasuji 《Researches on Population Ecology》1993,35(1):23-29
Summary Dispersal propensity of green leafhoppers was compared between a tropical species,Nephotettix virescens, and a temperate species,N. cincticeps. The flight ability was measured with tethered flight technique under laboratory conditions (25°C, 16L-8D). The pre-flight
period was shorter and the flight duration was longer inN. virescens than inN. cincticeps in both sexes. No significant correlations were found between the flight activity and morphometric characters for either
of the two species. The results suggested that dispersal propensity ofN. virescens is higher than that ofN. cincticeps. 相似文献
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Combining spiral of silence theory with the situational theory of problem solving, this study explores the extent to which publics differ in their willingness to express their opinions in hostile social situations. Based on analysis of a survey among 369 college students about their willingness to express opinions on 2 controversial topics (gun possession and climate change), 3 key findings emerge: (a) Fear of isolation suppresses people's willingness to express their opinions in public; (b) active publics are more likely than other types of publics to express their opinions; and (c) there is no interaction effect between fear of isolation and types of publics. In addition to several theoretical contributions, the findings provide public relations practitioners with a model for predicting which types of publics would be more or less likely to express their opinion. 相似文献