Stable Sort A stable sort is one where two records with a field that compares as equal will retain their order if sorted according to that field. This is a property of the sorting algorithm, not of the comparison mechanism. For example, a bubble sort is stable, while a Quicksort is not. This is a useful property, but cannot be accomplished by modifications to the comparison mechanism or tailorings.
Product metrics describe the characteristics of the product such as size, complexity, design features, performance, and quality level. Process metrics can be used to improve software development and maintenance. Examples include the effectiveness of defect removal during development, the pattern of testing defect arrival, and the response time of the fix process.
Project metrics describe the project characteristics and execution.
Examples include the number of software developers, the staffing pattern over the life cycle of the software, cost, schedule, and productivity. Some metrics belong to multiple categories.
For example, the in-process quality metrics of a project are both process metrics and project metrics. Software quality metrics are a subset of software metrics that focus on the quality aspects of the product, process, and project. In general, software quality metrics are more closely associated with process and product metrics than with project metrics.
Nonetheless, the project parameters such as the number of developers and their skill levels, the schedule, the size, and the organization structure certainly affect the quality of the product.
Software quality metrics can be divided further into end-product quality metrics and in-process quality metrics. The essence of software quality engineering is to investigate the relationships among in-process metrics, project characteristics, and end-product quality, and, based on the findings, to engineer improvements in both process and product quality.
Moreover, we should view quality from the entire software life-cycle perspective and, in this regard, we should include metrics that measure the quality level of the maintenance process as another category of software quality metrics.
In this chapter we discuss several metrics in each of three groups of software quality metrics: In the last sections we also describe the key metrics used by several major software developers and discuss software metrics data collection.
The metrics we discuss here cover both levels: Mean time to failure Customer problems Customer satisfaction. Intrinsic product quality is usually measured by the number of "bugs" functional defects in the software or by how long the software can run before encountering a "crash.
The MTTF metric is most often used with safety-critical systems such as the airline traffic control systems, avionics, and weapons.
For instance, the U. In civilian airliners, the probability of certain catastrophic failures must be no worse than per hour Littlewood and Strigini, The defect density metric, in contrast, is used in many commercial software systems. The two metrics are correlated but are different enough to merit close attention.
First, one measures the time between failures, the other measures the defects relative to the software size lines of code, function points, etc.
Second, although it is difficult to separate defects and failures in actual measurements and data tracking, failures and defects or faults have different meanings. An error is a human mistake that results in incorrect software. The resulting fault is an accidental condition that causes a unit of the system to fail to function as required.
A defect is an anomaly in a product. A failure occurs when a functional unit of a software-related system can no longer perform its required function or cannot perform it within specified limits.
From these definitions, the difference between a fault and a defect is unclear. For practical purposes, there is no difference between the two terms. Indeed, in many development organizations the two terms are used synonymously.
In this book we also use the two terms interchangeably. Simply put, when an error occurs during the development process, a fault or a defect is injected in the software.
In operational mode, failures are caused by faults or defects, or failures are materializations of faults. Sometimes a fault causes more than one failure situation and, on the other hand, some faults do not materialize until the software has been executed for a long time with some particular scenarios.
Therefore, defect and failure do not have a one-to-one correspondence. Third, the defects that cause higher failure rates are usually discovered and removed early. The probability of failure associated with a latent defect is called its size, or "bug size. For general-purpose computer systems or commercial-use software, for which there is no typical user profile of the software, the MTTF metric is more difficult to implement and may not be representative of all customers.
Fourth, gathering data about time between failures is very expensive. It requires recording the occurrence time of each software failure. It is sometimes quite difficult to record the time for all the failures observed during testing or operation.Every regional economy has its own distinct profile of clusters.
In order to standardize clusters and allow for useful comparisons of clusters across regions, the U.S. Cluster Mapping Project provides a set of benchmark cluster definitions (or cluster categories) that are the same in all U.S.
regions, whether they are states, economic areas, metropolitan statistical areas, or counties. Comparison and contrast of project definitions Robert K.
Haycocks gives two definitions of a project In his book “Effective Project Management: Traditional, Agile, Extreme”. The first one Is defined as “common”, and will be referred as such In this essay.
After the recent announcement of the Series Seed Financing documents by Marc Andreesen, Brad Feld points out that there are now four sets of “open source” equity seed financing documents. TechStars Model Seed Funding Documents (by Cooley); Y Combinator Series AA Equity Financing Documents (by WSGR); Founders Institute Plain Preferred Term Sheet (by WSGR – disclaimer, I represent the.
(used relatively in restrictive clauses having that as the antecedent): Damaged goods constituted part of that which was sold at the auction. (used after a preposition to represent a specified antecedent): the horse on which I rode.
(used relatively to represent a specified or implied antecedent) the one that; a particular one that: You may choose which you like. Comparison and Contrast Guide: This student-centered online guide provides a thorough introduction to the compare and contrast essay format, including definitions, transitions, graphic organizers, checklists, and examples.
Comparison and contrast essay Comparison and contrast essay is one of the most common assignments in American high schools and universities.
In this type of essay students have to compare two (in some essays several) things, problems, events or ideas and evaluate their resemblances and differences.