Test Estimation is one of the most difficult and critical activitivities in a software development project. Test Estimation should be realistic and accurate. Estimation is not only about to calculation of the efforts but also of what would be tested and by whom.

1. Things To Consider for Test Estimation
Test Estimation is one of the most difficult and critical activitivities in a
software development project. Test Estimation should be realistic and
accurate. Estimation is not only about to calculation of the efforts but also of
what would be tested and by whom. Normally the development team with
out any or just a little participation only took the software decisions from the
testing team. Test estimations play an integral role in the project
management and estimations.
Estimations should be:
1. Realistic: It should include all the tasks that you can reasonably
anticipate. It forecasts what, based on our current knowledge, is most likely
to happen. It reveals the risks to a test project so you can take steps to
mitigate them.
2. Actionable: There must be clear definitions as to who the assigned
resources are and what dependencies are acceptable and who will own what
tasks and activities.
3. Flexible: What if deadline and resource constraints are immovable? The
estimation must accommodate project realities.
For the success of any project or software, the project test estimation and
proper execution plays an important role. Normally the testers and
developers of that software or the product have to stick to a defined process
and get the deliverables done and in time. Good timely delivery plays a
really important role to build a credible reputation.
The Test Estimation is a necessity but the question arises why do we need to
do the Test Estimations?
Test Estimation is necessary while doing the planning for the testing activity.
Currently test estimation techniques are aplenty. User can select any of
techniques as per the requirement and comfort. For that users do not have
to learn or adopt any new things. These estimations are the ones where one
has to take decisions. While estimating the project or about testing, the
experience plays a crucial role how? Simply, the more you have experience
the more realistic decision you can make. It helps to prepare an accurate
estimation.
Estimations are also helpful and utilized for outsourced software testing and
third party testing services identification and budget calculations. But mere
estimations do not ensure a timely delivery. It requires clear understanding
necessary infrastructure, technical expertise and knowledge for a delivery.
Testing estimations have to have a clear understanding as to what is
required and how it is going to be achieved for a timely and accurate
delivery.
Below are the Factors that affect the estimation effort

2. Things To Consider for Test Estimation
- Market Opportunities
- Volatility of requirement
- Experience
- Organization strength
- Skill or technical knowledge
- Ability
- Technology
There are certain additional and important considerations that play a major
role while doing the estimation.
Following are the briefings
- Buffer time
- Consideration of the bug life cycle.
- Availability of the resources for estimated period.
- Parallel testing
- Re- visiting the estimations frequently because estimation can have
deviations
- Experience both of the estimator and the resources getting involved
- Scope of the project
- Testing types that you are going to test
- About team strengths, weaknesses and domain knowledge
- Methods going to be used.
Additionally allow enough time to do proper estimation. Refer past
documented data and use your own estimates. Take several opinions if
required from the experienced people and use the best technique for
achieving it. Re- Estimate the project several times throughout its life cycle
and create the standardized procedure so that it will be helpful for another
estimation and improve it as per the industry standards.
Quiet truly as one master added "Estimations estimate the estimator"
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