这样基本确定测试时间。作者: zhangjm1688 时间: 2008-11-4 16:37 标题: 准确评估测试工作量比较难,大家可以参考一下国外的经验噢! Following are some approaches to consider
Implicit Risk Context Approach:
A typical approach to test estimation is for a project manager or QA manager to implicitly use risk context, in combination with past personal experiences in the organization, to choose a level of resources to allocate to testing. In many organizations, the 'risk context' is assumed to be similar from one project to the next, so there is no explicit consideration of risk context. (Risk context might include factors such as the organization's typical software quality levels, the software's intended use, the experience level of developers and testers, etc.) This is essentially an intuitive guess based on experience.
Metrics-Based Approach:
A useful approach is to track past experience of an organization's various projects and the associated test effort that worked well for projects. Once there is a set of data covering characteristics for a reasonable number of projects, then this 'past experience' information can be used for future test project planning. (Determining and collecting useful project metrics over time can be an extremely difficult task.) For each particular new project, the 'expected' required test time can be adjusted based on whatever metrics or other information is available, such as function point count, number of external system interfaces, unit testing done by developers, risk levels of the project, etc. In the end, this is essentially 'judgement based on documented experience', and is not easy to do successfully.
Test Work Breakdown Approach:
Another common approach is to decompose the expected testing tasks into a collection of small tasks for which estimates can, at least in theory, be made with reasonable accuracy. This of course assumes that an accurate and predictable breakdown of testing tasks and their estimated effort is feasible. In many large projects, this is not the case. For example, if a large number of bugs are being found in a project, this will add to the time required for testing, retesting, bug analysis and reporting. It will also add to the time required for development, and if development schedules and efforts do not go as planned, this will further impact testing.
Iterative Approach:
In this approach for large test efforts, an initial rough testing estimate is made. Once testing begins, a more refined estimate is made after a small percentage (eg, 1%) of the first estimate's work is done. At this point testers have obtained additional test project knowledge and a better understanding of issues, general software quality, and risk. Test plans and schedules can be refactored if necessary and a new estimate provided. Then a yet-more-refined estimate is made after a somewhat larger percentage (eg, 2%) of the new work estimate is done. Repeat the cycle as necessary/appropriate.
Percentage-of-Development Approach:
Some organizations utilize a quick estimation method for testing based on the estimated programming effort. For example, if a project is estimated to require 1000 hours of programming effort, and the organization normally finds that a 40% ratio for testing is appropriate, then an estimate of 400 hours for testing would be used. This approach may or may not be useful depending on the project-to-project variations in risk, personnel, types of applications, levels of complexity, etc.
Successful test estimation is a challenge for most organizations, since few can accurately estimate software project development efforts, much less the testing effort of a project. It is also difficult to attempt testing estimates without first having detailed information about a project, including detailed requirements, the organization's experience with similar projects in the past, and an understanding of what should be included in a 'testing' estimation for a project (functional testing? unit testing? reviews? inspections? load testing? security testing?)
With agile software development approaches, test effort estimations may be unnecessary if pure test-driven development is utilized. However, it is not uncommon to have a mix of some automated positive-type unit tests, along with some type of separate manual or automated functional testing. In general, agile-based projects by their nature will not be heavily dependent on large testing efforts, since they emphasize the construction of releasable software in very short iteration cycles. These smaller test effort estimates may not be as difficult and the impact of inaccurate estimates will be less severe.作者: 阿七 时间: 2008-11-4 21:26
zhanwei作者: yongzhao 时间: 2008-11-4 21:58
14楼的英语是不是很好啊····我看了半天··不懂啊
郁闷ing作者: yongzhao 时间: 2008-11-4 21:59
14楼的英语是不是很好啊····我看了半天··不懂啊
郁闷ing作者: wtfc 时间: 2008-11-5 09:35 标题: zhuzx,你当了版主就不到每周一问来答题啦?? 强烈期待您的高见???作者: zhuzx 时间: 2008-11-5 09:52 标题: 朋友,这期我一定回答,呵呵!!
2.开发时间的百分比法Percentage of development time。 这个方法的基本前提是测试工作量依赖于开发时间/开发工作量。首先,开发工作量使用例如LOC或FP方法被估算出来,然后使用一些探索性的方法来限制测试的工作量。
这种方法变化比较大而且通常基于以前的经验。
通常预留项目的总花费时间的35%给测试。? 5-7%给组件和集成测试? 18-20%给系统测试? 10%给接收测试(或回归测试等)