A software development and resource estimation method of deriving a change in product amount when a number of times of specification modifications occur during software development to estimate a development scale, the software development and resource estimation method comprising:
- using a software development and resource estimation system comprising an I/O unit configured to recognize, transmit, and output development information, which is information on a specification modification input through a terminal by a user during the software modification, a database configured to accumulate environmental information on the software development on which the specification modification is performed, and a computer including a specification modification estimation calculation unit configured to calculate the estimation of a development scale in the specification modification using the information input from the I/O unit and the information stored in the database and to transmit the calculated estimation to the I/O unit, wherein the specification modification estimation calculation unit sequentially executes the following steps:
- an initial scale calculation step of requesting and obtaining an influence rate representing a degree of influence on a software development environment by each quality characteristic of software set and stored in the database when the development information is received from the I/O unit, and calculating a development scale before the specification modification as an initial development scale by multiplying a product amount baseline representing a standard development scale of the software included in the development information by a value obtained by adding 1 to a total sum of influence rates;
- a yield calculation step of requesting and obtaining a product amount from the database at a time of generating a development unit when a modification target development unit included in the initial development scale of the initial scale calculation step and the development information are received, and calculating a yield which is a ratio of the initial development scale to the product amount;
- a specification modification ratio calculation step of receiving a rejection amount of a product or an additional amount of a product, which are included in the development information, and the initial development scale from the initial development scale calculation step when the product is rejected or added due to the specification modification, and calculating a specification modification ratio, which is a ratio of the rejection amount of the product or the additional amount of the product to the initial development scale;
- an entire development scale calculation step of receiving the initial development scale, the yield, and the specification modification ratio from the initial scale calculation step, the yield calculation step, and the specification modification ratio calculation step, respectively, deriving a resultant development scale which is obtained by adding 1 to a total sum of the specification modification ratios to a specification modification of each development unit obtained by multiplying the initial development scale by the yield, and calculating an entire development scale caused by a plurality of specification modifications by totaling the development scales of all development units;
- a specification modification amount calculation step of calculating a specification modification amount which is a modification amount of the product amount due to the specification modification based on the entire development scale calculation step received in the entire development scale calculation step;
- a specification modification correction step of receiving a rejection net ratio, calculated by the specification modification ratio calculation step, which is a comparative ratio between the rejection amount of a product and the initial scale, and the entire development scale from the entire development scale calculation step when the specification modification causes declination in the number of the specification modification between processes in respect to the specification modification amount, correcting the specification modification ratio by subtracting the received rejection net ratio, and calculating a corrected entire development scale;
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- an entire development scale output step of outputting and displaying the development scale and the entire development scale transmitted in the entire development scale calculation step, the specification modification amount transmitted in the specification modification amount calculation step, and the corrected entire development scale transmitted in the specification modification correction step on the terminal of the user.