scholarly journals Rationalizing rational expectations: Characterizations and tests

2021 ◽  
Vol 12 (3) ◽  
pp. 817-842 ◽  
Author(s):  
Xavier D'Haultfoeuille ◽  
Christophe Gaillac ◽  
Arnaud Maurel
Keyword(s):  
Measurement Errors ◽  
Null Hypothesis ◽  
Rational Expectations ◽  
Data Sets ◽  
Aggregate Shocks ◽  
Future Earnings ◽  
Subjective Beliefs ◽  
The Common ◽  
Common Situation ◽  
Mean Preserving Spread

In this paper, we build a new test of rational expectations based on the marginal distributions of realizations and subjective beliefs. This test is widely applicable, including in the common situation where realizations and beliefs are observed in two different data sets that cannot be matched. We show that whether one can rationalize rational expectations is equivalent to the distribution of realizations being a mean‐preserving spread of the distribution of beliefs. The null hypothesis can then be rewritten as a system of many moment inequality and equality constraints, for which tests have been recently developed in the literature. The test is robust to measurement errors under some restrictions and can be extended to account for aggregate shocks. Finally, we apply our methodology to test for rational expectations about future earnings. While individuals tend to be right on average about their future earnings, our test strongly rejects rational expectations.

Ḥadith ‘Āishah fī Man’i al-Nisā’ Min al-Masājid; Niqāsh ‘Ulamā’ Bangladesh Ḥaulahu

2020 ◽  
Vol 9 (1) ◽  
pp. 97-115
Author(s):  
Syed Mahmudul Hasan
Keyword(s):  
Analytical Method ◽  
Inductive Method ◽  
The Common ◽  
The Difference ◽  
Common Situation

The Narration of Aisyah (May Allah be pleased with her), is the main focus of the controversy among Bangladeshi scholars on the issue of women's prayer in the mosque. The reason for the dispute is that a group of them issued the ruling based on the phenomenon of the text, and the others explained the ruling of Hadith according to the common situation in the society. If the circumstances change, the ruling will change along with it, because the originality of the issue is permissible, that is proven from other texts. This research adopts an inductive method to survey the Prophetic hadiths that talk about the prayer of women in the Mosque in terms of permissibility and prohibition and analytical method to analyze the difference in opinion of Bangladeshi scholars related to this issue. The research finds that the ruling of Shari’ah is a process that is continuous and permanent. But in necessity and emergency, it has the notion of flexibility and explanation. In the issue of women’s presence in the mosque, they should be allowed if they abide by the suggestions of Prophet (s) and should not if they don’t. So, Prohibition is not from the prophet (s), but it is from their obedience to the ruling.

scholarly journals AA-HMM: An Anti-Adversarial Hidden Markov Model for Network-Based Intrusion Detection

2018 ◽  
Vol 8 (12) ◽  
pp. 2421 ◽  
Author(s):  
Chongya Song ◽  
Alexander Pons ◽  
Kang Yen
Keyword(s):  
Markov Model ◽  
Hidden Markov Model ◽  
Performance Metrics ◽  
Hidden Markov ◽  
Data Sets ◽  
Learning Abilities ◽  
Benchmark Data ◽  
Malicious Behavior ◽  
Network Intrusion ◽  
The Common

In the field of network intrusion, malware usually evades anomaly detection by disguising malicious behavior as legitimate access. Therefore, detecting these attacks from network traffic has become a challenge in this an adversarial setting. In this paper, an enhanced Hidden Markov Model, called the Anti-Adversarial Hidden Markov Model (AA-HMM), is proposed to effectively detect evasion pattern, using the Dynamic Window and Threshold techniques to achieve adaptive, anti-adversarial, and online-learning abilities. In addition, a concept called Pattern Entropy is defined and acts as the foundation of AA-HMM. We evaluate the effectiveness of our approach employing two well-known benchmark data sets, NSL-KDD and CTU-13, in terms of the common performance metrics and the algorithm’s adaptation and anti-adversary abilities.

scholarly journals PEDAGOGICAL PRACTICE AS A KEY TO REAL PEDAGOGUE’S SUCCESS SOLUTION

2013 ◽  
Vol 6 (1) ◽  
pp. 4-5
Author(s):  
Vincentas Lamanauskas
Keyword(s):  
Education System ◽  
Scientific Research ◽  
Scientific Conference ◽  
Pedagogical Practice ◽  
Psychological Preparation ◽  
University Studies ◽  
State Pedagogical ◽  
The Common ◽  
Organizational Mechanisms ◽  
Common Situation

Pedagogical practice preparing future teachers is, undoubtedly, one of the most important elements of university studies. However, up to now pedagogical practice remains a very problematic sphere. Pedagogical activity, on the whole, is complicated, diverse and manifold. After all, it is an activity requiring creativity, high intellect and good psychological preparation. A student doing pedagogical practice, inevitably encounters various hardships -both specialty/professional and psychological. During the practice many different kinds of pedagogical situations are revealed. Various scientific research studies, carried out in the last few years, show the common situation – students-practitioners lack psychological preparation in communication with students, adjusting to a new environment, understanding them and so on. Actually, pedagogical practice theoretical and practical questions were discussed in the international scientific conference which took place between 1- 5 July, 2013 in Yerevan (Armenia). The conference under the theme „Modernization of Continuous Practice and Implementation of Organizational Mechanisms in the Higher Pedagogical Education System“ was organised by Armenian State Pedagogical University named after Khachatur Abovyan.

A Review of the Common DDoS Attack: Types and Protection Approaches Based on Artificial Intelligence

2021 ◽  
pp. 08-14
Author(s):  
Nafea ali majeed .. ◽  
◽  
◽  
◽  
Khalid Hameed Zaboon ◽  
...  
Keyword(s):  
Web Applications ◽  
Data Sets ◽  
Cyber Attack ◽  
Ddos Attacks ◽  
Ddos Attack ◽  
Test Characteristics ◽  
Global Force ◽  
The Common ◽  
Evaluation Techniques ◽  
The Web

Recently, the technology become an important part of our live, and it is employed to work together with the Medicine, Space Science, Agriculture, and industry and more else. Stored the information in the servers and cloud become required. It is a global force that has transformed people's lives with the availability of various web applications that serve billions of websites every day. However, there are many types of attack could be targeting the internet, and there is a need to recognize, classify and protect thesis types of attack. Due to its important global role, it has become important to ensure that web applications are secure, accurate, and of high quality. One of the basic problems found on the Web is DDoS attacks. In this work, the review classifies and delineates attack types, test characteristics, evaluation techniques; evaluation methods and test data sets used in the proposed Strategic Strategy methodology. Finally, this work affords guidance and possible targets in the fight against creating better events to overcome the most dangers Cyber-attack types which is DDoS attacks.

A model of the distribution and metabolism of corticotropin-releasing factor

1988 ◽  
Vol 254 (1) ◽  
pp. E104-E112
Author(s):  
B. Candas ◽  
J. Lalonde ◽  
M. Normand
Keyword(s):  
Measurement Errors ◽  
Compartment Model ◽  
Corticotropin Releasing Factor ◽  
Data Sets ◽  
Data Set ◽  
Rapid Injection ◽  
Three Compartment Model ◽  
Rival Models ◽  
Sampling Schedule ◽  
Selection Of

The aim of this study is the selection of the number of compartments required for a model to represent the distribution and metabolism of corticotropin-releasing factor (CRF) in rats. The dynamics of labeled rat CRF were measured in plasma for seven rats after a rapid injection. The sampling schedule resulted from the combination of the two D-optimal sampling sets of times corresponding to both rival models. This protocol improved the numerical identifiability of the parameters and consequently facilitated the selection of the relevant model. A three-compartment model fits adequately to the seven individual dynamics and better represents four of them compared with the lower-order model. It was demonstrated, using simulations in which the measurement errors and the interindividual variability of the parameters are included, that his four-to-seven ratio of data sets is consistent with the relevance of the three-compartment model for every individual kinetic data set. Kinetic and metabolic parameters were then derived for each individual rat, their values being consistent with the prolonged effects of CRF on pituitary-adrenocortical secretion.

TESTING TIME-SERIES STATIONARITY AGAINST AN ALTERNATIVE WHOSE MEAN IS PERIODIC

2001 ◽  
Vol 5 (3) ◽  
pp. 380-412 ◽  
Author(s):  
Melvin A. Hinich ◽  
Phillip Wild
Keyword(s):  
Time Series ◽  
Fourier Transform ◽  
Real World ◽  
Null Hypothesis ◽  
Data Sets ◽  
Testing Time ◽  
Economic Data ◽  
The Mean ◽  
Important Form ◽  
Real World Problems

We develop a test of the null hypothesis that an observed time series is a realization of a strictly stationary random process. Our test is based on the result that the kth value of the discrete Fourier transform of a sample frame has a zero mean under the null hypothesis. The test that we develop will have considerable power against an important form of nonstationarity hitherto not considered in the mainstream econometric time-series literature, that is, where the mean of a time series is periodic with random variation in its periodic structure. The size and power properties of the test are investigated and its applicability to real-world problems is demonstrated by application to three economic data sets.

Estimates of the size of winter flocks of the Pied Currawong, Strepera graculina (Shaw) from mark -recapture data - a new approach

1968 ◽  
Vol 16 (1) ◽  
pp. 27 ◽  
Author(s):  
JL Readshaw
Keyword(s):  
Population Size ◽  
Emigration And Immigration ◽  
New Method ◽  
Random Numbers ◽  
Sampling Effort ◽  
Mark Recapture ◽  
New Approach ◽  
The Common ◽  
Winter Flocks ◽  
Common Situation

Banding records were used to estimate the size of non-breeding winter flocks of the pied currawong, Strepera graculina, at Albury, N.S.W., during 1964 and 1965. A new method of analysing mark-recapture data is compared with conventional methods, and it is shown that the flocks contained between 500 and 1000 birds in both years. In 1964, the new method provided information on emigration and immigration that was not apparent when the data were treated in the conventional way. The new approach considers the common situation in which a population (flock) is sampled continuously by catching one member (bird) at a time, marking (banding) it, and returning it to the population. For closed populations, the population size was estimated by a method involving cumulative catch and recapture data. Subsequently, this method was successfully tested by simulating the sampling of 20 "populations" of 10,000 random numbers with a computer. The method also provided a simple way of controlling sampling effort based on recapture data to obtain any desired precision in the estimation of population size.

Revision of the Scopula dubernardi species group: how many species? (Lepidoptera: Geometridae, Sterrhinae)

Zootaxa ◽  
2006 ◽  
Vol 1164 (1) ◽  
pp. 35
Author(s):  
PASI SIHVONEN ◽  
DIETER STÜNING
Keyword(s):  
Species Delimitation ◽  
Male Genitalia ◽  
Species Group ◽  
Female Genitalia ◽  
Immature Stages ◽  
Separate Species ◽  
The Common ◽  
Common Situation

The Palaearctic Scopula dubernardi species group (Lepidoptera: Geometridae) is revised on the basis of external and genitalic characters to include Scopula dubernardi (Oberthür, 1923) and Scopula segregata Prout, 1919. Lectotypes are designated for both species, which were described from more than one specimen without holotype designation. The species delimitation is based on small quantitative differences in the female genitalia, i.e., the degree of turn of the ductus bursae along its axis, and on external features. Furthermore, the recognition of the studied taxa as separate species is strengthened by the observation that they occur sympatrically and synchronously in two localities. Unlike the common situation in the genus Scopula, structures of the male genitalia were found uninformative in species delimitation. The length of right ceras on the 8th sternite of S. segregata was found to be polymorphic. Adults and genitalia of S. dubernardi and S. segregata are illustrated, along with the variation in external features and genitalia in both species. The biology and immature stages of both species are unknown.

scholarly journals Identifying significantly impacted pathways: a comprehensive review and assessment

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Tuan-Minh Nguyen ◽  
Adib Shafi ◽  
Tin Nguyen ◽  
Sorin Draghici
Keyword(s):  
Pathway Analysis ◽  
Null Hypothesis ◽  
Large Scale ◽  
Data Sets ◽  
Actual Performance ◽  
Large Scale Assessment ◽  
Analysis Methods ◽  
Biological Phenomena ◽  
High Throughput Experiments ◽  
The Given

Abstract Background Many high-throughput experiments compare two phenotypes such as disease vs. healthy, with the goal of understanding the underlying biological phenomena characterizing the given phenotype. Because of the importance of this type of analysis, more than 70 pathway analysis methods have been proposed so far. These can be categorized into two main categories: non-topology-based (non-TB) and topology-based (TB). Although some review papers discuss this topic from different aspects, there is no systematic, large-scale assessment of such methods. Furthermore, the majority of the pathway analysis approaches rely on the assumption of uniformity of p values under the null hypothesis, which is often not true. Results This article presents the most comprehensive comparative study on pathway analysis methods available to date. We compare the actual performance of 13 widely used pathway analysis methods in over 1085 analyses. These comparisons were performed using 2601 samples from 75 human disease data sets and 121 samples from 11 knockout mouse data sets. In addition, we investigate the extent to which each method is biased under the null hypothesis. Together, these data and results constitute a reliable benchmark against which future pathway analysis methods could and should be tested. Conclusion Overall, the result shows that no method is perfect. In general, TB methods appear to perform better than non-TB methods. This is somewhat expected since the TB methods take into consideration the structure of the pathway which is meant to describe the underlying phenomena. We also discover that most, if not all, listed approaches are biased and can produce skewed results under the null.

scholarly journals Common metabolic networks contribute to carbon sink strength of sorghum internodes: implications for bioenergy improvement

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Yin Li ◽  
Min Tu ◽  
Yaping Feng ◽  
Wenqin Wang ◽  
Joachim Messing
Keyword(s):  
Candidate Genes ◽  
Sweet Sorghum ◽  
Metabolic Networks ◽  
Carbon Allocation ◽  
Carbon Sink ◽  
Sink Strength ◽  
Primary Metabolism ◽  
Data Sets ◽  
Rna Seq ◽  
The Common

Abstract Background Sorghum bicolor (L.) is an important bioenergy source. The stems of sweet sorghum function as carbon sinks and accumulate large amounts of sugars and lignocellulosic biomass and considerable amounts of starch, therefore providing a model of carbon allocation and accumulation for other bioenergy crops. While omics data sets for sugar accumulation have been reported in different genotypes, the common features of primary metabolism in sweet genotypes remain unclear. To obtain a cohesive and comparative picture of carbohydrate metabolism between sorghum genotypes, we compared the phenotypes and transcriptome dynamics of sugar-accumulating internodes among three different sweet genotypes (Della, Rio, and SIL-05) and two non-sweet genotypes (BTx406 and R9188). Results Field experiments showed that Della and Rio had similar dynamics and internode patterns of sugar concentration, albeit distinct other phenotypes. Interestingly, cellulose synthases for primary cell wall and key genes in starch synthesis and degradation were coordinately upregulated in sweet genotypes. Sweet sorghums maintained active monolignol biosynthesis compared to the non-sweet genotypes. Comparative RNA-seq results support the role of candidate Tonoplast Sugar Transporter gene (TST), but not the Sugars Will Eventually be Exported Transporter genes (SWEETs) in the different sugar accumulations between sweet and non-sweet genotypes. Conclusions Comparisons of the expression dynamics of carbon metabolic genes across the RNA-seq data sets identify several candidate genes with contrasting expression patterns between sweet and non-sweet sorghum lines, including genes required for cellulose and monolignol synthesis (CesA, PTAL, and CCR), starch metabolism (AGPase, SS, SBE, and G6P-translocator SbGPT2), and sucrose metabolism and transport (TPP and TST2). The common transcriptome features of primary metabolism identified here suggest the metabolic networks contributing to carbon sink strength in sorghum internodes, prioritize the candidate genes for manipulating carbon allocation with bioenergy purposes, and provide a comparative and cohesive picture of the complexity of carbon sink strength in sorghum stem.

Sign in / Sign up

Export Citation Format

Share Document