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Workshop on Emerging Trends in Software Metrics最新文献

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Assessing traditional and new metrics for object-oriented systems 评估面向对象系统的传统和新的度量标准
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809227
G. Concas, M. Marchesi, Alessandro Murgia, S. Pinna, R. Tonelli
We present an extensive analysis of software metrics for 111 object-oriented systems written in Java. For each system, we considered 18 traditional metrics such as LOC and Chidamber and Kemerer metrics, as well as metrics derived from complex network theory and social network analysis. These metrics were computed at class level. We also considered two metrics at system level, namely the total number of classes and interfaces, and the fractal dimension. We discuss the distribution of these metrics, and their correlation, both at class and at system level. We found that most metrics follow a leptokurtotic distribution. Only a couple of metrics have patent normal behavior while three others are very irregular, and even bimodal. The statistics gathered allow us to study and discuss the variability of metrics along different systems, and to devise a roadmap for further research.
我们对111个用Java编写的面向对象系统的软件度量进行了广泛的分析。对于每个系统,我们考虑了18个传统指标,如LOC、Chidamber和Kemerer指标,以及源自复杂网络理论和社会网络分析的指标。这些度量是在类级别上计算的。我们还考虑了系统级的两个度量,即类和接口的总数,以及分形维数。我们讨论这些度量的分布,以及它们在类和系统级别上的相关性。我们发现,大多数指标都遵循瘦峰度分布。只有几个指标具有专利的正常行为,而其他三个指标非常不规则,甚至是双峰的。收集到的统计数据使我们能够研究和讨论不同系统中度量的可变性,并为进一步的研究设计路线图。
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引用次数: 34
A metric model for aspects' coupling 方面耦合的度量模型
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809232
M. Bernardi, G. D. Lucca
Aspect Oriented Programming (AOP) introduces new types of coupling among the aspects and the components of the base system. Indeed, several and different new kinds of interactions among aspects and the other components can be introduced by the AOP constructs, allowing the alteration both of the structure, control and data flow of the components of the base system. These interactions can make higher the complexity of the overall system affecting its comprehension. In this paper we present a proposal for a metric model to classify the types of coupling among aspects and the components of the base system. The model can be used to define how each kind of coupling affects the complexity, and thus the comprehensibility, of the system.
面向方面编程(AOP)在基本系统的方面和组件之间引入了新的耦合类型。实际上,AOP构造可以引入方面和其他组件之间的几种不同的新类型的交互,从而允许改变基本系统组件的结构、控制和数据流。这些交互可以提高整个系统的复杂性,从而影响其理解。在本文中,我们提出了一个度量模型来划分基本系统的各个方面和组件之间的耦合类型。该模型可用于定义每种耦合如何影响系统的复杂性,从而影响系统的可理解性。
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引用次数: 5
Does size matter?: a preliminary investigation of the consequences of powerlaws in software 大小重要吗?对软件中权力法则的影响的初步调查
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809226
Joshua Lindsay, J. Noble, E. Tempero
There is increasing evidence that many object-oriented software size metrics are characterised by scale-free, powerlaw distributions. This means programs will have arbitrarily large components, and the size of the largest component will increase as programs' overall size increases. This directly contradicts a crucial assumption of object-oriented design --- that large programs can be build by combining many small components. In this paper, we present a preliminary study of this contradiction. We illustrate the distribution of several size metrics over a corpus of 100 Java systems, and then investigate the largest classes (according to five size and complexity metrics) from one of those systems. We find that, while some large classes may be explained by code-generation or design patterns, most large classes were examples of poor object-oriented design.
越来越多的证据表明,许多面向对象的软件大小度量都以无标度、幂律分布为特征。这意味着程序将具有任意大的组件,并且最大组件的大小将随着程序总体大小的增加而增加。这直接与面向对象设计的一个关键假设相矛盾——大型程序可以通过组合许多小组件来构建。在本文中,我们对这一矛盾进行了初步研究。我们将在100个Java系统的语料库上说明几个大小指标的分布,然后研究其中一个系统中最大的类(根据五个大小和复杂性指标)。我们发现,虽然一些大类可以用代码生成或设计模式来解释,但大多数大类都是糟糕的面向对象设计的例子。
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引用次数: 5
On the use of weighted sums in the definition of measures 论加权和在测度定义中的应用
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809225
S. Morasca
Several widely used functionality measures, quality models, and other measures have been defined in Empirical Software Engineering by using weighted sums. The apparent simplicity in the definition and interpretation of weighted sums make them one of the preferred ways for defining new measures. However, they have a few inherent issues that may make their definition and use quite problematic. This paper provides a critical investigation about the intuition behind weighted sums and their theoretical and empirical validation pitfalls that may make them questionable when used in the definition of meaningful and practically useful measures. Using estimation models may alleviate at least some of the problems with weighted sums.
在经验软件工程中,一些广泛使用的功能度量、质量模型和其他度量已经通过使用加权和来定义。加权和的定义和解释显然简单,这使其成为定义新度量的首选方法之一。然而,它们有一些固有的问题,可能使它们的定义和使用相当有问题。本文对加权和背后的直觉及其理论和经验验证陷阱进行了批判性调查,这些陷阱可能使它们在定义有意义和实际有用的度量时受到质疑。使用估计模型至少可以减轻加权和的一些问题。
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引用次数: 9
Problems adopting metrics from other disciplines 采用其他学科指标的问题
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809224
B. Kitchenham, P. Brereton
In this paper, we argue that metrics validation approaches used in software engineering are problematic. In particular, theoretical validation is not rigorous enough to detect invalid metrics and empirical validation has no mechanism for making any final decisions about the validity of metrics. In addition, we argue that cohesion and information-theoretic metrics are problematic if they are based on mathematical graphs which do not consider program semantics. We conclude that we should not adopt metrics from other disciplines if we cannot validate them properly. We propose the use of the representation condition as a means to demonstrate metrics that are not valid. We also believe that design metrics must make sense to software designers or, even if they are valid, they will not be used.
在本文中,我们认为在软件工程中使用的度量验证方法是有问题的。特别是,理论验证不够严格,无法检测无效的度量标准,而经验验证没有机制可以对度量标准的有效性做出任何最终决定。此外,我们认为,如果内聚和信息论度量基于不考虑程序语义的数学图,则它们是有问题的。我们得出结论,如果我们不能正确地验证其他学科的指标,我们就不应该采用它们。我们建议使用表示条件作为证明无效指标的手段。我们也相信设计度量对软件设计师来说必须是有意义的,否则即使它们是有效的,也不会被使用。
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引用次数: 6
Is a strategy for code smell assessment long overdue? 代码气味评估策略是不是姗姗姗姗来?
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809228
S. Counsell, R. Hierons, H. Hamza, S. Black, M. Durrand
Code smells reflect code decay and, as such, developers should seek to eradicate such smells through application of 'deodorant' in the form of one or more refactorings. However, a dearth of studies exploring code smells either theoretically or empirically suggests that there are reasons why smell eradication is neither being applied in anger, nor the subject of significant research. In this paper, we present three studies as supporting evidence for this claim. The first is an analysis of a set of five, open-source Java systems, the second an empirical study of a sub-system of a proprietary, C# web-based application and the third, a theoretical enumeration of smell-related refactorings. Key findings of the study were first, that developers seemed to avoid eradicating superficially 'simple' smells in favor of more 'obscure' ones; second, a wide range of conflicts and anomalies soon emerged when trying to identify smelly code. Finally, perceived effort to eradicate a smell may be a key factor. The study highlights the need for a clearer research strategy on the issue of code smells and all aspects of their identification and measurement.
代码气味反映了代码的腐烂,因此,开发人员应该通过一个或多个重构形式的“除臭剂”应用来消除这种气味。然而,缺乏从理论上或经验上探索代码气味的研究表明,气味消除既没有应用于愤怒,也没有成为重要研究的主题,这是有原因的。在本文中,我们提出了三个研究作为支持这一说法的证据。第一部分是对五个开源Java系统的分析,第二部分是对一个专有的基于c#的应用程序的子系统的实证研究,第三部分是对气味相关重构的理论列举。该研究的主要发现是,首先,开发人员似乎避免消除表面上“简单”的气味,而倾向于更“晦涩”的气味;其次,在试图识别有臭味的代码时,很快就会出现大量的冲突和异常。最后,消除气味的感知努力可能是一个关键因素。该研究强调了在代码气味问题及其识别和测量的所有方面需要一个更清晰的研究策略。
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引用次数: 14
On the relationship between functional size and software code size 论功能大小与软件代码大小的关系
Pub Date : 2010-05-04 DOI: 10.1145/1809223.1809230
Kenneth Lind, Rogardt Heldal
SLOC (Source Lines-Of-Code) has been used extensively as a Code Size Measure, and as input to parametric software cost and effort estimation tools. SLOC is obtained by measuring FP (Function Points) on the requirements and multiplying by the SLOC/FP ratio from similar projects. This is done even though several studies show large variations in this ratio, due to weak correlation between FP and SLOC. However, in our previous experiments we have obtained strong correlation between CFP (COSMIC Function Points) and Bytes compiled code as Code Size Measure. The experiments were conducted in the automotive industry using software components developed by GM (General Motors). In this paper we explain the reasons behind the strong correlation. The main reasons are that we apply the COSMIC method on software components of similar type, with a 1-to-1 mapping to COSMIC. A strong correlation between the Functional Size Measure and the Code Size Measure is required to obtain accurate Code Size estimation results. To estimate the Code Size before the software is available, is important both for Cost/Effort estimation and design of electronic hardware.
源代码行数(Source Lines-Of-Code)已经被广泛用作代码大小度量,并作为参数化软件成本和工作量估计工具的输入。SLOC是通过测量需求上的FP(功能点)并乘以来自类似项目的SLOC/FP比率来获得的。尽管有几项研究表明,由于FP和SLOC之间的相关性较弱,这一比例存在很大差异,但还是可以做到这一点。然而,在我们之前的实验中,我们已经获得了CFP (COSMIC功能点)和字节编译代码作为代码大小度量之间的强相关性。实验是在汽车工业中使用通用汽车公司开发的软件组件进行的。在本文中,我们解释了强相关性背后的原因。主要原因是我们在类似类型的软件组件上应用了COSMIC方法,并对COSMIC进行了1对1的映射。为了获得准确的代码大小估计结果,需要功能大小度量和代码大小度量之间有很强的相关性。在软件可用之前估计代码大小,对于成本/工作量估计和电子硬件设计都很重要。
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引用次数: 12
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Workshop on Emerging Trends in Software Metrics
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