Research on Software Development Project Cost

Cost management is one of the main contents of software project management. It analyzes the problems existing in the current software development cost management process, and puts forward to consider linking progress with cost, the method that matches the workload with the actual cost. Based on the existing estimation method, the cost management system is designed and applied to the software project management platform to improve the cost overruns in software development and improve the efficiency of enterprises.

Keywords software project management platform cost estimation Cost Control

With the rapid development of information technology, the software industry plays an increasingly important role in the national economy. Effective management of software development is a crucial factor that determines the development of the software industry. In the process of software project development, project management has received increasing attention. Software project management is an activity for analyzing and managing costs, personnel, progress, quality, and risks to enable software projects to be completed smoothly According to the predefined costs, progress, and quality. Cost management is a major part of software project management. As for the current development, cost management is a weak aspect of software project management, as a result, the cost of software costs increases and the quality of software cannot be guaranteed. In view of these phenomena, this paper proposes a new cost management method and applies it to the development of the software project management platform, a subject under study, in order to facilitate the development of effective software project management tools, saving costs for enterprises and improving economic efficiency.

1. Cost Management Overview
Project cost management includes ensuring that all processes required for the project are completed within the approved budget range [1]. The management of software project costs can be summarized by estimation and control. First, the software cost is estimated, and then a Cost Management Plan is formed. During the software project development process, control software projects so that they can proceed as planned. A Cost Management Plan is the standard for cost control. an unreasonable plan may cause the project to be out of control and exceed the budget. Therefore, cost estimation is the basis of the entire cost management process, and cost control is to make the project cost within the budget range during the development process.
1.1 Cost Management Process
Software project cost management is to use the company's established resources based on the company's situation and specific project requirements to ensure that the project progress and quality reach the customer's satisfaction, effectively organize, implement, control, track, analyze, and assess software project costs to minimize project costs and increase project profits.
The cost management process includes [1]:
· Resource plans, including deciding what resources (personnel, equipment and materials) are required for implementation of project activities and the amount of each resource. The main output is a list of resource requirements. · Cost estimation, including an approximate estimate of the resource costs required for completing the project. The main output is the cost management plan.
· Cost budgeting, including configuring the entire cost estimate to individual tasks to establish a benchmark plan for measuring performance. The main output is the cost benchmark plan.
· Cost control, including controlling changes to the project budget. It mainly outputs revised cost estimates, budget updates, corrective actions and lessons learned.

1.2 Main Problems in Software Development Cost Management
(1) The accuracy of project cost budget and estimation is poor.
Due to the constant changes in customer requirements, the work content and workload are constantly changing. Once a change occurs, the Project Manager adds the project budget and frequently changes the budget. When the project ends, the actual cost and initial plan deviate greatly.

In addition, the project budget tends to go through two extremes: rough and meticulous. A rough budget may lead to high project costs and lower accuracy. A low budget may lead to excessive project control content, poor flexibility, inflexible changes, and increased management costs.

(2) Lack of effective control over the prior estimation of software costs.
In the initial stage of development, the cost is not concerned enough, and the cost control is ignored. The cost control is implemented only when the project is in the later stage and the project is actually far away from the planned deviation, this often leads to project budget exceeding.
(3) Lack of Cost Performance Analysis and tracking.
In traditional project cost management, the budget is compared with the actual value, but the budget, actual cost and workload progress are rarely linked, considering whether the actual cost and workload match.

1.3 improvement of cost management methods
Currently, common software project management tools focus on some functions. For example, Microsoft project2000 focuses on managing and planning tasks and tracking these tasks during project execution, focusing on schedule and tracking control, RUP focuses on the description of user requirements, and PVCs focuses on software change management. These software project management tools are constantly improving their functions. Although there are also cost management functions, most of them cannot be used for Software Cost Estimation and lack of prior cost control, it cannot be automatically coordinated with estimated data, and cannot be used in historical databases. The current project management tools cannot meet the needs of cost management.
Aiming at the problems in the above cost management process and the shortcomings of software project management tools, this paper proposes an improved management method, associate progress with cost to consider how to match workload with actual cost. In addition, combined with the existing cost estimation method, the process database is introduced into the software project management, and the prototype design of the cost management system is given. The system uses advanced estimation methods to solve the problem of low cost estimation accuracy. The workload and actual cost matching methods are used for Cost Performance Analysis and tracking so that the project cost can be controlled within the budget range.

2. Cost Management System Design

2.1 Overall System Design
Although there are already a lot of project management software, it is generally only about managing the software progress and tracking and supervision. It is independent of software estimation, and there is no software project cost management software yet, we take this as a guide to study the particularity of the software development process. Combined with the existing software cost estimation technology and the general industry project management technology, we take progress, personnel, costs, and changes as the center, the specific implementation scheme of software cost management is proposed. The system functions are analyzed and designed on this basis.
2.2 System Function Design
(1) cost estimation is a very important part of project cost management. Precise software cost estimation is an essential part of effective software management. Common Software estimation methods include Algorithm Model, expert determination, and analogy estimation. These methods have their own advantages and disadvantages. In this paper, the methods mentioned in [2] are used to combine the methods and learn from each other. The weights of various estimation methods are obtained by the AHP, and then the cost is estimated by the weighting synthesis method. It can improve the accuracy of software cost estimation.
Define F1, F2, medium, and FM as the estimated values of M models, and WI (I =, medium, m) as the weights of I models, then f = is the weight combination estimation model.
Assume that the cocomo model [3] is used to estimate the cost of MM1, tdev1, mm2 and tdev2 by Delphi, and mm3 and tdev3 by analogy estimation, it is estimated from the weight combination that Mm = w1mm1 + w2mm2 + w3mm3 tdev = W1 tdev1 + W2 tdev2 + W3 tdev3 here mm is the number of persons required for software development, and tdev is the software development cycle. (2) The budget change management can record every resource and cost change and maintain a complete and annotated historical record.
(3) The cost benchmark plan is the standard for cost control. Even if the best project manager uses the best cost estimation method, it is impossible to make the budget completely consistent with the actual cost. Therefore, the project cost estimation should reserve 5%-10% of the total cost as an unpredictable cost for emergency project cost over cost estimation and budget. The benchmark of cost control is that the project management personnel determine the allowable deviation range based on the specific project conditions. During a project, the cost benchmark plan is not static, but may be continuously corrected as the user's needs change.
(4) A progress plan consists of a control plan and an execution plan, allowing you to query the progress plan and the actual progress status in real time. Cost Estimation is usually associated with the workload. The cost tracking and control process is also the process of executing and adjusting the progress plan.
(5) The cost control is to control the changes in the project budget according to the cost benchmark plan, the main output of the cost control process is revised cost estimates, budget updates, corrective actions, completion estimates, and lessons learned. Cost Performance Analysis and tracking compare the budget with the actual value, link the budget cost, actual cost and workload progress, and check whether the actual cost and workload match. Solution 2 that matches the actual cost and workload of the system. If the actual cost does not match the actual progress, re-adjust the plan and take necessary measures to prevent the project cost from being out of control.
(6) The process database stores the historical data of the project's cost management process. It consists of the data of completed projects. These data can be used for cost estimation, cost planning, and performance analysis. In addition to providing a basis for new project cost plans, it can also provide real-time process data for ongoing projects. In the initial baseline plan development period, the reference plan and execution plan are developed based on the historical process metric data of similar projects in the past. Store the process metric data during the project development and execution process to the database as the empirical data for the next development plan. In this way, the plan is getting closer and closer to reality.

3 conclusion
This article discusses the shortcomings of some existing software project management systems, and does not associate the budget, workload, and actual progress to achieve effective cost management, this paper proposes an improved cost management method, which can accurately estimate and effectively control cost management, and provides a systematic design. However, due to the complexity of software project management, although the methods proposed in this paper help to solve the estimation and control problems in cost management, it is still impossible to do a very good job, if we can strike a balance between cost and progress and quality, it is bound to have great practical value for the project management of software enterprises.