Accuracy and efficacy of estimates

Which parameter  is an important factor that can affect the accuracy and efficacy of estimates? What describes the data and control to be processed? A number of independent investigators have developed a team-oriented approach to requirements gathering that can be applied to establish the scope of a project called CLSS stands for The project planner examines the statement of scope and extracts all important software functions which is known as The environment that supports the software project is called Which element is not an option to achieve reliable cost and effort estimate? What can be used to complement decomposition techniques and offer a potentially valuable estimation approach in their own right? Which item  is not achieved by an automated estimation tools? Software project estimation can never be an exact science, but a combination of good historical data and systematic techniques can improve estimation accuracy.