Putnam-Norden-Rayleigh Curve

In the study of software project scheduling, the Putnam-Norden-Rayleigh Curve, also known as the PNR Curve, is a graphical curve derived from a mathematical equation that indicated the relationship between applied effort and delivery time in relation to a software project. A PNR curve can be used to determine the least cost time for delivery $t\_o$ up to the limit $t\_\{min\}$, the absolute minimal amount of time required to complete the project no matter how many human resources are added. The PNR curve was used to derive the Software equation.cite book|last=Pressman|first=Roger S.|authorlink=Roger S. Pressman|title=Software Engineering - A Practitioner's Approach|origdate=1982|edition=6th|publisher=McGraw-Hill|location=Newyork, NY|year=2005|isbn=0-07-285318-2|pages=678-679]

Equation

The following equation shows the relationship of project effort as a function of project delivery time.

:$E\_a=m\; left\; (\; frac$t_d}^4}t_a}^4} ight )

Where
*$E\_a$=Effort in person months
*$t\_d$=The nominal delivery time for the schedule
*$t\_a$=Actual delivery time desired

ee also

*Software equation"'effort=a1*(kloc)^d1"'

References