International Journal of Computer Applications (0975 – 8887) Volume 103 – No.9, October 2014 39 Software Effort Estimation: A Fuzzy Logic Approach Vishal Chandra AI, SGVU Jaipur, Rajasthan, India ABSTRACT There are many equation based effort estimation models like Bailey-Basil Model, Halstead Model, and Walston-Felix Model. Effort and Cost estimation are the major concern of any sort of software industry. They are calculated with the help of Kilo Line Code (KLOC) which are the number of, line of code in software. For example if a software contain 1000 lines then it has 1 kilo line of codes. There are several ways to estimate it with various advantages and disadvantages. We can distinguish them in two parts, one is equation based and another is model based estimation techniques. In this paper a KLOC formula is proposed that calculate effort which is integrated with fuzzy logic. These components are vague and fuzzy easily handles them as well. Various fuzzy triangular membership functions are used in this paper. One of the most popular model is COCOMO [5] and its variants, which is mostly used in the industry, along with the other variants such as fuzzy approach, neuro fuzzy approach and cost driver based estimations. There are differences between Equation Based and Model Based effort estimation techniques, model based built on specific model, like architecture & available resources whereas equation based techniques follows some back- ground equations. Keywords Empirical Equation, fuzzy logic, effort estimation, membership functions, KLOC. 1. INTRODUCTION Software engineers try to estimate effort & cost with an accuracy in the software industry. The major target of the software engineering community is to develop useful models that can explain precisely predict the effort. There are many empirical equation based software estimation models had been developed over the last two- four decades , that were based on efforts estimation like Jones and Software Productivity Research‟s[2], Checkpoint model, Putnam and Quantitative Software Measurement‟s [8], SLIM model, Park[1] and PRICE Systems‟ PRICE-S model, Jensen and the SEER SEM model, Rubin and the Estimacs model and Boehm and the COCOMO model [Putnam, 1992, Jones, 1997, Park, 1988, Jensen, 1983, Rubin, 1983, Boehm, 1981, Boehm, 1995, Walkerden, 1997, Conte, 1986, Fenton, 1991, Masters, 1985, Mohanty, 1981]. These approaches impose a few restrictions, often violated by software engineering data and resulted in the development of inaccurate empirical models that do not perform very well when used for prediction of effort. This paper focuses on approximate effort estimation with the help of equation which is related to kilo line of codes (KLOC) and fuzzy multiplier. This paper uses NASA project data set to validate the proposed model based on fuzzy parameters, there are many fuzzy parameters but I have chosen six they are as follows[8],:-  Qualification of Programmer  Experience with machine  Experience with Language  Experience with Application  Working experience of programmer  Complexity  Storage  Required reuse  Facilities  Development schedule  Product reliability and complexity  Analytical capability These are vague properties which cannot be measured in terms of traditional mathematical theory or crisp theory. Fuzzy works between two rigid boundaries which we say between 0 and 1 or between yes and no. There are various factors in which effort estimation depends, in this paper only few (five) common properties are taken. This model is very useful in estimating small, medium and large projects which have any amount of KLOC. 2. LITRETURE SURVEY In last few decades a large number of software development effort estimation techniques are developed. Software estimation techniques are broadly categorized in six categories they are as follows [10].  Model based  Learning oriented  Dynamic Based  Expertise based  Composite  Regression Based 2.1 Halstead Model [3]. This model was developed by Halstead. Source code and formulates a relation [4] EFFORT =0.7 × ܮܭ 1.15 (1) 2.2 Bailey-Basil Model [2]. This model developed by Bailey- Basil between delivered lines of source code and [2] formulates a relation EFFORT = 5.5 × ܮܭ 1.16 (2) 2.3 Walston-Felix Model: - Walton and Felix (1977) developed their effort model from a various aspects of the software development environment such as user database of sixty projects collected in IBM's Federal Systems division. It provides a relationship between delivered lines of source code. This model constitutes participation, customer-oriented changes, memory constraints etc. [6].