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1.
Evolutionary learning of hierarchical decision rules   总被引:2,自引:0,他引:2  
This paper describes an approach based on evolutionary algorithms, hierarchical decision rules (HIDER), for learning rules in continuous and discrete domains. The algorithm produces a hierarchical set of rules, that is, the rules are sequentially obtained and must therefore be tried until one is found whose conditions are satisfied. Thus, the number of rules may be reduced because the rules could be inside of one another. The evolutionary algorithm uses both real and binary coding for the individuals of the population. We tested our system on real data from the UCI repository, and the results of a ten-fold cross-validation are compared to C4.5s, C4.5Rules, See5s, and See5Rules. The experiments show that HIDER works well in practice.  相似文献   

2.
This paper studies some decision rules for ambulance scheduling. The scheduling decision rules embedded in the decision support systems for emergency ambulance scheduling consider the criteria on the average response time and the percentage of the ambulance requests that are responded within 15 min, which is usually ignored in traditional scheduling policies. The challenge in designing the decision rules lies in the stochastic and dynamic nature of request arrivals, fulfillment processes, and complex traffic conditions as well as the time-dependent spatial patterns of some parameters complicate the decisions in the problem. To illustrate the proposed decision rules’ usage in practice, a simulator is developed for performing some numerical experiments to validate the effectiveness and the efficiency of the proposed decision rules.  相似文献   

3.
While rule based control (RBC) is current practice in most building automation systems that issue discrete control signals, recent simulation studies suggest that advanced, optimization based control methods such as hybrid model predictive control (HMPC) can potentially outperform RBC in terms of energy efficiency and occupancy comfort. However, HMPC requires a more complex IT infrastructure and numerical optimization in the loop, which makes commissioning, operation of the building, and error handling significantly more involved than in the rule based setting. In this paper, we suggest an automated RBC synthesis procedure for binary decisions that extracts prevalent information from simulation data with HMPC controllers. The result is a set of simple decision rules that preserves much of the control performance of HMPC. The methods are based on standard machine learning algorithms, in particular support vector machines (SVMs) and adaptive boosting (AdaBoost). We consider also the ranking and selection of measurements which are used for a decision and show that this feature selection is useful in both complexity reduction and reduction of investment costs by pruning unnecessary sensors. The suggested methods are evaluated in simulation for six different case studies and shown to maintain the performance of HMPC despite a tremendous reduction in complexity.  相似文献   

4.
The authors study distributed decision networks where uncertainties exist in the statistical environment. Specifically each decision maker (DM) has an unknown probability to be jammed or defective and an unknown probability to provide an incorrect decision when jammed or defective. Each DM in the network has the ability to process its input data consisting of external observations and decisions from preceding DMs, to produce a decision regarding an underlying binary hypothesis testing problem. The local observations are assumed conditionally independent given each hypothesis. The resulting binary hypothesis testing problem is solved using some simple concepts of Dempster-Shafer theory. The performance of the proposed decision rule is compared to that of the minimax decision rule and the decision rule that is optimum when there are no jammed or defective DMs for several distributed decision networks with different topologies. It is shown that the proposed decision rule has a very robust behavior  相似文献   

5.
A novel class of ensembles of linear decision rules is introduced which includes majority voting-based ensembles as a particular case. Based on this general framework, new results are given that state the ability of a subclass to discriminate between two infinite subsets A and B in R n , thus generalizing Mazurov’s theorem for two finite sets.  相似文献   

6.
Linearized decision rules in the aggregate production scheduling framework are compared through simulation experiments to see if decisions are improved when adaptive feedback elements are built into the rule. Our results, based on some non-parametric tests, show the need for determining an optimal trade-off between stabilization and experimentation through a specified cost functional.  相似文献   

7.
Evolutionary policy iteration for solving Markov decision processes   总被引:1,自引:0,他引:1  
We propose a novel algorithm called evolutionary policy iteration (EPI) for solving infinite horizon discounted reward Markov decision processes. EPI inherits the spirit of policy iteration but eliminates the need to maximize over the entire action space in the policy improvement step, so it should be most effective for problems with very large action spaces. EPI iteratively generates a "population" or a set of policies such that the performance of the "elite policy" for a population monotonically improves with respect to a defined fitness function. EPI converges with probability one to a population whose elite policy is an optimal policy. EPI is naturally parallelizable and along this discussion, a distributed variant of PI is also studied.  相似文献   

8.

在序决策信息系统中, 定义区间为支配一个特定的对象同时又被另一个特定的对象所支配的所有对象的集合. 以区间为基本知识颗粒, 建立新的优势关系粗糙集模型, 并由此获取决策值为特定区间范围的区间决策规则. 提出区间的约简的概念, 构造区分函数计算区间的约简, 并由此计算优化区间决策规则. 该方法比初始的优势关系粗糙集方法适应性更强, 且所得区间决策规则可直接应用于序信息系统的分类问题.

  相似文献   

9.
粒计算中决策规则的提取   总被引:1,自引:1,他引:0       下载免费PDF全文
为从决策表中获取最简决策规则,在研究粒计算理论的基础上,提出了一种基于粒计算的决策规则提取算法。该算法通过引入λ阶粒库的概念,利用粒计算的方法对由同一决策表所生成的粒库,从不同的角度和多个层次进行研究,尝试从较低阶的粒库中提取出尽可能多的具有一定规则覆盖度与置信度的简洁规则。最后通过实例验证了该算法的有效性。  相似文献   

10.
In this paper, we present a fusion rule for distributed multihypothesis decision systems where communication patterns among sensors are given and the fusion center may also observe data. It is a specific form of the most general fusion rule, independent of statistical characteristics of observations and decision criteria, and thus, is called a unified fusion rule of the decision system. To achieve globally optimum performance, only sensor rules need to be optimized under the proposed fusion rule for the given conditional distributions of observations and decision criterion. Following this idea, we present a systematic and efficient scheme for generating optimum sensor rules and hence, optimum fusion rules, which reduce computation tremendously as compared with the commonly used exhaustive search. Numerical examples are given, which support the above results and provide a guideline on how to assign sensors to nodes in a signal detection networks with a given communication pattern. In addition, performance of parallel and tandem networks is compared.  相似文献   

11.
12.
在决策算法中,并不是所有的决策规则都是必要的,一些过剩的决策规则应该消去,而不影响作决策,因此,研究最小化决策规则集的计算方法是很有意义的.传统的决策算法并没有给出最小化决策规则集的形式化计算方法,为了解决最小化决策规则集的形式化计算问题,引入了最小化决策规则可辨识矩阵概念,提供了基于可辨识矩阵的基本决策规则的最小化决策规则集的计算方法.  相似文献   

13.
We use the theory of order statistics, the concepts of first- and second-order stochastic dominance (FSD and SSD) to develop an order statistics SSD minimax decision rule. It can be used to refine choice within the random variables in the SSD noninferior set. We are able to reduce the size of the SSD noninferior set when we assume that the decision-maker is most concerned about the potential adverse outcomes at the right tail of the probability distribution. In other words, we consider the risk of extreme events and build on order statistics in order to refine the decision rules. In some eases, the order statistics SSD minimax decision rule can provide us with a unique choice from among the SSD noninferior set. We define the concept of conditional second-order stochastic dominance (CSSD) in order to model the risk of extreme events. We also use the concept of CSSD to develop a CSSD minimax decision rule  相似文献   

14.
We study the possibility of constructing decision trees with evolutionary algorithms in order to increase their predictive accuracy. We present a self-adapting evolutionary algorithm for the induction of decision trees and describe the principle of decision making based on multiple evolutionary induced decision trees—decision forest. The developed model is used as a fault predictive approach to foresee dangerous software modules, which identification can largely enhance the reliability of software.  相似文献   

15.
Induction of decision rules plays an important role in machine learning. The main advantage of decision rules is their simplicity and human-interpretable form. Moreover, they are capable of modeling complex interactions between attributes. In this paper, we thoroughly analyze a learning algorithm, called ENDER, which constructs an ensemble of decision rules. This algorithm is tailored for regression and binary classification problems. It uses the boosting approach for learning, which can be treated as generalization of sequential covering. Each new rule is fitted by focusing on examples which were the hardest to classify correctly by the rules already present in the ensemble. We consider different loss functions and minimization techniques often encountered in the boosting framework. The minimization techniques are used to derive impurity measures which control construction of single decision rules. Properties of four different impurity measures are analyzed with respect to the trade-off between misclassification (discrimination) and coverage (completeness) of the rule. Moreover, we consider regularization consisting of shrinking and sampling. Finally, we compare the ENDER algorithm with other well-known decision rule learners such as SLIPPER, LRI and RuleFit.  相似文献   

16.
17.
基于二进制可辨矩阵的决策规则约简算法   总被引:1,自引:1,他引:1  
决策规则的约简是利用决策逻辑分别消去每一条决策规则中的冗余属性值,是粗糙集理论知识约简的重要内容,一般是在属性约简之后采用启发式信息实现决策规则的约简。基于二进制可辨矩阵给出一个简单的直接求取决策规则核的方法,并提出一种决策规则的约简算法。所给算法简单直观,不但适用于相容决策表,也适用于不相容的决策表。  相似文献   

18.
The passenger’s perception of the airport’s level of service (LOS) may have a significant impact on promoting or discouraging future tourism and business activities. In this study, we take a look at this problem, but unlike in traditional statistical analysis, we apply a new method, the dominance-based rough set approach (DRSA), to an airport service survey. A set of “if  then  ” decision rules is used in the preference model. The passengers indicate their perception of airport LOS by rating a set of criteria/attributes. The proposed method provides practical information that should be of help to airport planners, designers, operators, and managers to develop LOS improvement strategies. The model was implemented using survey data from a large sample of customers from an international airport in Taiwan.  相似文献   

19.
贾桂霞  张永 《计算机工程与设计》2006,27(12):2175-2177,2186
在数据挖掘领域,关联规则的挖掘和基于粗糙集理论抽取决策规则是两种截然不同的方法,但在统计意义下两种方法产生的规则基本相同。结合关联规则挖掘方法和粗糙集方法的优点,基于Apriori算法提出一种优化算法,获取具有一定支持度和可信度阈值且不产生冗余的决策规则,以提高粗糙集属性值约简算法的性能。  相似文献   

20.
When classes strongly overlap in the feature space, or when some classes are not known in advance, the performance of a classifier heavily decreases. To overcome this problem, the reject option has been introduced. It simply consists in withdrawing the decision, and let another classifier, or an expert, take the decision whenever exclusively classifying is not reliable enough. The classification problem is then a matter of class-selection, from none to all classes. In this paper, we propose a family of measures suitable to define such decision rules. It is based on a new family of operators that are able to detect blocks of similar values within a set of numbers in the unit interval, the soft labels of an incoming pattern to be classified, using a single threshold. Experiments on synthetic and real datasets available in the public domain show the efficiency of our approach.  相似文献   

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