Chapter 3 Parametric Estimating

Question 1

Building a parametric model includes _________ , _________ , and ___________

Answer 1

collecting data, identifying cost drivers, and developing CERs.

Question 2

What is the difference between cost passengers and cost drivers

Answer 2

Cost passengers are major system components that represent the majority of the system’s cost.
Cost drivers represent those design decisions and requirements at a system-level that truly influence the amount of money spent on an item

Question 3

A _____ predicts cost via a simple multiplicative relationship. Which are always expressed in dollars per parameter.

Answer 3

rate

Question 4

A ______ uses the cost of one element to predict the cost of another via a simple multiplicative relationship.

Answer 4

factor

Question 5

A ______ estimates effort and is defined as parameter on parameter. For example, if a program plans to perform Commercial Off-The-Shelf (COTS) software integration within the software baseline, a good ______ to use is the industry average of 1,200 lines of code per integrated package.

Answer 5

Ratio

Question 6

What are the five top-level steps to the regression process?

Answer 6

1.)Select the Variables: Determine the independent (source) variable (e.g., LOC, number of deployments, COTS procurements, etc.), data collection methodology, and data type corresponding to the desired analysis.
2.) Test Relationships: After selecting the variables, test for associations that may exist between each variable and cost.
3.)Perform Regression: After initial inspection and testing of the data, perform regression analysis to develop the equation to use in the model
4.) Select CERs: Select the CER that best represents the data.
5.) Validate CERs: Finally, validate the CER on the representative data that was not used to develop the equation.

Question 7

__________ of a CER is defined as resetting the
y-intercept (or equivalently the constant term) of the CER to force it to pass through a desired point (pair of coordinates).

Answer 7

Calibration

Question 8

The _________ represents the ratio of explained variation to total variation in the data set. It provides an estimate of how explanatory the independent variable, cost driver, is.

Answer 8

R2 value (R squared)

Question 9

_________ occurs when there is a significant correlation between two cost drivers and it is unlikely that both cost drivers will be good explanatory variables at the same time.

Answer 9

Multicollinearity