Modeling Group Size and Scalar Stress by Logistic Regression from an Archaeological Perspective

A manifest trend is that larger and more productive human groups shift from distributed to centralized decision-making. Voluntary theories propose that human groups shift to hierarchy to limit scalar stress, i.e. the increase in cost of organization as a group grows. Yet, this hypothesis lacks a mechanistic model to investigate the organizational advantage of hierarchy and its role on its evolution. To fill this gap, we describe social organization by the distribution of individuals’ capacity to influence others. We then integrate this formalization into models of social dynamics and evolutionary dynamics. First, our results demonstrate that hierarchy strongly reduces scalar stress, and that this benefit can emerge solely because leaders and followers differ in their capacity to influence others. Second, the model demonstrates that this benefit can be sufficient to drive the evolution of leader and follower behaviours and ultimately, the transition from small egalitarian to large hierarchical groups.

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Nomogram Model to Predict the Probability of Ovarian Hyperstimulation Syndrome in the Treatment of Patients With Polycystic Ovary Syndrome

Frontiers in Endocrinology ◽

10.3389/fendo.2021.619059 ◽

2021 ◽

Vol 12 ◽

Author(s):

Fei Li ◽

Ying Chen ◽

Aiqin Niu ◽

Yajing He ◽

Ying Yan

Keyword(s):

Risk Factors ◽

Logistic Regression ◽

Polycystic Ovary Syndrome ◽

Ovarian Hyperstimulation Syndrome ◽

Polycystic Ovary ◽

Receiver Operating Curve ◽

Ovarian Hyperstimulation ◽

Ovary Syndrome ◽

Modeling Group ◽

Independent Risk Factors

ObjectiveThe objective of this study was to explore the risk factors of ovarian hyperstimulation syndrome (OHSS) in patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) and to establish a nomogram model evaluate the probability of OHSS in PCOS patients.MethodsWe retrospectively analyzed clinical data from 4,351 patients with PCOS receiving IVF/ICSI in our reproductive medical center. The clinical cases were randomly divided into a modeling group (3,231 cases) and a verification group (1,120 cases) according to a ratio of about 3:1. The independent risk factors correlation with the occurrence of OHSS was identified by logistic regression analysis. Based on the selected independent risk factors and correlated regression coefficients, we established a nomogram model to predict the probability of OHSS in PCOS patients, and the predictive accuracy of the model was measured using the area under the receiver operating curve (AUC).ResultsUnivariate and multivariate logistic regression analyses showed that FSH (OR, 0.901; 95% CI, 0.847–0.958; P<0.001), AMH (OR, 1.259; 95% CI, 1.206–1.315; P<0.001), E2 value on the day of hCG injection (OR, 1.122; 95% CI, 1.021–1.253; P<0.001), total dosage of Gn used (OR, 1.010; 95% CI, 1.002–1.016; P=0.041), and follicle number on the day of hCG injection (OR, 0.134; 95% CI, 1.020–1.261; P=0.020) are the independent risk factors for OHSS in PCOS patients. The AUC of the modeling group is 0.827 (95% CI, 0.795–0.859), and the AUC of the verification group is 0.757 (95% CI, 0.733–0.782).ConclusionThe newly established nomogram model has proven to be a novel tool that can effectively, easily, and intuitively predict the probability of OHSS in the patients with PCOS, by which the clinician can set up a better clinical management strategies for conducting a precise personal therapy.

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An ecological basis for large group size in Colobus angolensis in the Nyungwe Forest, Rwanda

African Journal of Ecology ◽

10.1046/j.1365-2028.2001.00276.x ◽

2001 ◽

Vol 39 (1) ◽

pp. 83-92 ◽

Cited By ~ 10

Author(s):

Cheryl Fimbel ◽

Amy Vedder ◽

Ellen Dierenfeld ◽

Felix Mulindahabi

Keyword(s):

Group Size ◽

Large Group ◽

Colobus Angolensis ◽

Ecological Basis

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Ancestral Maya Economies in Archaeological Perspective

10.1017/cbo9781139195867 ◽

2010 ◽

Cited By ~ 49

Author(s):

Patricia A. McAnany

Keyword(s):

Archaeological Perspective

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How Useful is the Power Law of Practice for Recognizing Practice in Concentration Tests?

European Journal of Psychological Assessment ◽

10.1027/1015-5759.23.3.157 ◽

2007 ◽

Vol 23 (3) ◽

pp. 157-165 ◽

Cited By ~ 4

Author(s):

Carmen Hagemeister

Keyword(s):

Logistic Regression ◽

Reaction Time ◽

Power Law ◽

Error Rate ◽

Reaction Times ◽

Practice Effect ◽

Practice Effects ◽

Rate Decrease ◽

Small Practice

Abstract. When concentration tests are completed repeatedly, reaction time and error rate decrease considerably, but the underlying ability does not improve. In order to overcome this validity problem this study aimed to test if the practice effect between tests and within tests can be useful in determining whether persons have already completed this test. The power law of practice postulates that practice effects are greater in unpracticed than in practiced persons. Two experiments were carried out in which the participants completed the same tests at the beginning and at the end of two test sessions set about 3 days apart. In both experiments, the logistic regression could indeed classify persons according to previous practice through the practice effect between the tests at the beginning and at the end of the session, and, less well but still significantly, through the practice effect within the first test of the session. Further analyses showed that the practice effects correlated more highly with the initial performance than was to be expected for mathematical reasons; typically persons with long reaction times have larger practice effects. Thus, small practice effects alone do not allow one to conclude that a person has worked on the test before.

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Perceived Effectiveness of Random Testing for Alcohol and Drugs in the Australian Aviation Community

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000031 ◽

2012 ◽

Vol 2 (2) ◽

pp. 72-81

Author(s):

Christina M. Rudin-Brown ◽

Eve Mitsopoulos-Rubens ◽

Michael G. Lenné

Keyword(s):

Logistic Regression ◽

Online Survey ◽

Random Testing ◽

Regression Analyses ◽

Perceived Effectiveness ◽

Student Pilots ◽

Alcohol And Drugs ◽

Positive Attitudes ◽

One Year ◽

Alcohol And Other Drugs

Random testing for alcohol and other drugs (AODs) in individuals who perform safety-sensitive activities as part of their aviation role was introduced in Australia in April 2009. One year later, an online survey (N = 2,226) was conducted to investigate attitudes, behaviors, and knowledge regarding random testing and to gauge perceptions regarding its effectiveness. Private, recreational, and student pilots were less likely than industry personnel to report being aware of the requirement (86.5% versus 97.1%), to have undergone testing (76.5% versus 96.1%), and to know of others who had undergone testing (39.9% versus 84.3%), and they had more positive attitudes toward random testing than industry personnel. However, logistic regression analyses indicated that random testing is more effective at deterring AOD use among industry personnel.

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