scholarly journals Heterogeneous population dynamical model: a filtering problem

2005 ◽  
Vol 42 (02) ◽  
pp. 346-361 ◽  
Author(s):  
A. Gerardi ◽  
P. Tardelli
Keyword(s):  
Finite Number ◽  
Conditional Distribution ◽  
Heterogeneous Population ◽  
Time Approximation ◽  
Stochastic Filtering ◽  
Discrete Time Approximation ◽  
Different Types ◽  
Number Of Classes ◽  
Filtering Problem ◽  
Over Time

We consider a heterogeneous population of identical particles divided into a finite number of classes according to their level of health. The partition can change over time, and a suitable exchangeability assumption is made to allow for having identical items of different types. The partition is not observed; we only observe the cardinality of a particular class. We discuss the problem of finding the conditional distribution of particle lifetimes, given such observations, using stochastic filtering techniques. In particular, a discrete-time approximation is given.

scholarly journals Heterogeneous population dynamical model: a filtering problem

2005 ◽  
Vol 42 (2) ◽  
pp. 346-361 ◽  
Author(s):  
A. Gerardi ◽  
P. Tardelli
Keyword(s):  
Finite Number ◽  
Conditional Distribution ◽  
Heterogeneous Population ◽  
Time Approximation ◽  
Stochastic Filtering ◽  
Discrete Time Approximation ◽  
Different Types ◽  
Number Of Classes ◽  
Filtering Problem ◽  
Over Time

We consider a heterogeneous population of identical particles divided into a finite number of classes according to their level of health. The partition can change over time, and a suitable exchangeability assumption is made to allow for having identical items of different types. The partition is not observed; we only observe the cardinality of a particular class. We discuss the problem of finding the conditional distribution of particle lifetimes, given such observations, using stochastic filtering techniques. In particular, a discrete-time approximation is given.

scholarly journals Controlled Heterogeneous Collection: The Role of Occupation Numbers

2008 ◽  
Vol 45 (03) ◽  
pp. 595-609 ◽  
Author(s):  
A. Gerardi ◽  
P. Tardelli
Keyword(s):  
Class A ◽  
Finite Dimensional ◽  
Occupation Numbers ◽  
Discrete Time Approximation ◽  
Wear And Tear ◽  
Set Up ◽  
Number Of Classes ◽  
Filtering Problem ◽  
The Value Function

A controlled heterogeneous collection of identical items is presented. According to their level of wear and tear, they are divided into a finite number of classes and the partition of the collection is allowed to change over time. A suitable exchangeability assumption is made to preserve the property that the items be identical. The role of the occupation numbers is investigated and a filtering problem is set up, where the observation is the cardinality of a particular class. A control on the dynamics of the items is introduced, and the existence of an optimal control is proved. A discrete-time approximation for the separated problem, which is a finite-dimensional one, is performed. As a consequence, an approximation for the value function is given.

Filtering equations for the conditional law of residual lifetimes from a heterogeneous population

2000 ◽  
Vol 37 (3) ◽  
pp. 823-834 ◽  
Author(s):  
A. Gerardi ◽  
F. Spizzichino ◽  
B. Torti
Keyword(s):  
Random Vector ◽  
Probabilistic Model ◽  
Conditional Distribution ◽  
Heterogeneous Population ◽  
Main Assumption ◽  
Stochastic Filtering ◽  
Occupation Numbers ◽  
History Of ◽  
Residual Lifetimes

We consider a probabilistic model of a heterogeneous population P subdivided into homogeneous sub-cohorts. A main assumption is that the frailties give rise to a discrete, exchangeable random vector. We put ourselves in the framework of stochastic filtering to derive the conditional distribution of residual lifetimes of surviving individuals, given an observed history of failures and survivals. As a main feature of our approach, this study is based on the analysis of behaviour of the vector of ‘occupation numbers’.

scholarly journals Congestion-dependent pricing in a stochastic service system

2007 ◽  
Vol 39 (04) ◽  
pp. 898-921 ◽  
Author(s):  
Idriss Maoui ◽  
Hayriye Ayhan ◽  
Robert D. Foley
Keyword(s):  
Finite Number ◽  
Service Provider ◽  
Queueing System ◽  
Service System ◽  
Pricing Policy ◽  
Holding Costs ◽  
State Dependent ◽  
Long Run ◽  
Number Of Classes ◽  
Over Time

We study a service facility modeled as a queueing system with finite or infinite capacity. Arriving customers enter if there is room in the facility and if they are willing to pay the price posted by the service provider. Customers belong to one of a finite number of classes that have different willingnesses-to-pay. Moreover, there is a penalty for congestion in the facility in the form of state-dependent holding costs. The service provider may advertise class-specific prices that may fluctuate over time. We show the existence of a unique optimal stationary pricing policy in a continuous and unbounded action space that maximizes the long-run average profit per unit time. We determine an expression for this policy under certain conditions. We also analyze the structure and the properties of this policy.

scholarly journals Controlled Heterogeneous Collection: The Role of Occupation Numbers

2008 ◽  
Vol 45 (3) ◽  
pp. 595-609 ◽  
Author(s):  
A. Gerardi ◽  
P. Tardelli
Keyword(s):  
Class A ◽  
Finite Dimensional ◽  
Occupation Numbers ◽  
Discrete Time Approximation ◽  
Wear And Tear ◽  
Set Up ◽  
Number Of Classes ◽  
Filtering Problem ◽  
The Value Function

A controlled heterogeneous collection of identical items is presented. According to their level of wear and tear, they are divided into a finite number of classes and the partition of the collection is allowed to change over time. A suitable exchangeability assumption is made to preserve the property that the items be identical. The role of the occupation numbers is investigated and a filtering problem is set up, where the observation is the cardinality of a particular class. A control on the dynamics of the items is introduced, and the existence of an optimal control is proved. A discrete-time approximation for the separated problem, which is a finite-dimensional one, is performed. As a consequence, an approximation for the value function is given.

Filtering equations for the conditional law of residual lifetimes from a heterogeneous population

2000 ◽  
Vol 37 (03) ◽  
pp. 823-834 ◽  
Author(s):  
A. Gerardi ◽  
F. Spizzichino ◽  
B. Torti
Keyword(s):  
Random Vector ◽  
Probabilistic Model ◽  
Conditional Distribution ◽  
Heterogeneous Population ◽  
Main Assumption ◽  
Stochastic Filtering ◽  
Occupation Numbers ◽  
History Of ◽  
Residual Lifetimes

We consider a probabilistic model of a heterogeneous population P subdivided into homogeneous sub-cohorts. A main assumption is that the frailties give rise to a discrete, exchangeable random vector. We put ourselves in the framework of stochastic filtering to derive the conditional distribution of residual lifetimes of surviving individuals, given an observed history of failures and survivals. As a main feature of our approach, this study is based on the analysis of behaviour of the vector of ‘occupation numbers’.

scholarly journals Congestion-dependent pricing in a stochastic service system

2007 ◽  
Vol 39 (4) ◽  
pp. 898-921 ◽  
Author(s):  
Idriss Maoui ◽  
Hayriye Ayhan ◽  
Robert D. Foley
Keyword(s):  
Finite Number ◽  
Service Provider ◽  
Queueing System ◽  
Service System ◽  
Pricing Policy ◽  
Holding Costs ◽  
State Dependent ◽  
Long Run ◽  
Number Of Classes ◽  
Over Time

We study a service facility modeled as a queueing system with finite or infinite capacity. Arriving customers enter if there is room in the facility and if they are willing to pay the price posted by the service provider. Customers belong to one of a finite number of classes that have different willingnesses-to-pay. Moreover, there is a penalty for congestion in the facility in the form of state-dependent holding costs. The service provider may advertise class-specific prices that may fluctuate over time. We show the existence of a unique optimal stationary pricing policy in a continuous and unbounded action space that maximizes the long-run average profit per unit time. We determine an expression for this policy under certain conditions. We also analyze the structure and the properties of this policy.

Measuring Agency Change Across the Domain of Hypnosis

2019 ◽  
Author(s):  
Vince Polito ◽  
Amanda Barnier ◽  
Erik Woody
Keyword(s):  
Rating Scale ◽  
Sense Of Agency ◽  
Pass Rates ◽  
Current Experiment ◽  
Multidimensional Construct ◽  
Time Points ◽  
Hypnotic Induction ◽  
Different Types ◽  
Over Time ◽  
Postexperimental Inquiry

Building on Hilgard’s (1965) classic work, the domain of hypnosis has been conceptualised by Barnier, Dienes, and Mitchell (2008) as comprising three levels: (1) classic hypnotic items, (2) responding between and within items, and (3) state and trait. The current experiment investigates sense of agency across each of these three levels. Forty-six high hypnotisable participants completed an ideomotor (arm levitation), a challenge (arm rigidity) and a cognitive (anosmia) item either following a hypnotic induction (hypnosis condition) or without a hypnotic induction (wake condition). In a postexperimental inquiry, participants rated their feelings of control at three time points for each item: during the suggestion, test and cancellation phases. They also completed the Sense of Agency Rating Scale (Polito, Barnier, & Woody, 2013) for each item. Pass rates, control ratings, and agency scores fluctuated across the different types of items and for the three phases of each item; also, control ratings and agency scores often differed across participants who passed versus failed each item. Interestingly, whereas a hypnotic induction influenced the likelihood of passing items, it had no direct effect on agentive experiences. These results suggest that altered sense of agency is not a unidimensional or static quality “switched on” by hypnotic induction, but a dynamic multidimensional construct that varies across items, over time and according to whether individuals pass or fail suggestions.

Imagery in the Book of Revelation

2020 ◽  
pp. 52-67
Author(s):  
Konrad Huber
Keyword(s):  
Reception History ◽  
Book Of Revelation ◽  
Imperial Cult ◽  
Emotional Effect ◽  
Greco Roman ◽  
Different Types ◽  
Figurative Speech ◽  
Theological Message ◽  
Over Time ◽  
The Way

The chapter first surveys different types of figurative speech in Revelation, including simile, metaphor, symbol, and narrative image. Second, it considers the way images are interrelated in the narrative world of the book. Third, it notes how the images draw associations from various backgrounds, including biblical and later Jewish sources, Greco-Roman myths, and the imperial cult, and how this enriches the understanding of the text. Fourth, the chapter looks at the rhetorical impact of the imagery on readers and stresses in particular its evocative, persuasive, and parenetic function together with its emotional effect. And fifth, it looks briefly at the way reception history shows how the imagery has engaged readers over time. Thus, illustrated by numerous examples, it becomes clear how essentially the imagery of the book of Revelation constitutes and determines its theological message.

scholarly journals Effect of scent on comfort of aircraft passengers

Work ◽  
2021 ◽  
Vol 68 (s1) ◽  
pp. S273-S280
Author(s):  
Xinhe Yao ◽  
Yu Song ◽  
Peter Vink
Keyword(s):  
Completion Time ◽  
Aircraft Cabin ◽  
Different Types ◽  
The Relationship ◽  
Over Time

BACKGROUND: Scents may influence the perceived comfort of an environment. There are only a few studies conducted on the relationship between scent and comfort in aircraft cabin. OBJECTIVES: The goal of this research is to explore whether relationships between scents and perceived comfort can be found for passengers in an aircraft cabin. METHODS: 276 participants joined an experiment in a Boeing 737 fuselage. The participants were divided into nine groups and each joined a session for 60 minutes with the exposure to different scents. The effect of the odor was measured by a set of questionnaires at the beginning and at the end of the session. Results of questionnaires were analyzed regarding the effects on the completion time, of the type of scents, of the intensity of the scent and on gender. RESULTS: Significant differences were found at the beginning and at the end of the experiment regarding comfort and emotion, but sometimes no relations could be established. The influence of different scents on comfort/discomfort varied and changed over time. However, in all scenarios, participant’ scores on emotion decreased. Additionally, the added scents influenced the linearity between the changes in comfort and discomfort. CONCLUSIONS: Smell could influence the perceived comfort/discomfort of aircraft passengers over time, and different types of smells have different effects on passengers. The preferences on scents are diverse, which highlights the need for personalization in aircraft cabin design.

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