Harmony search

In financial markets such as Tehran Stock Exchange, P/E coefficient, which is one of the most well-known instruments for evaluating stock prices in financial markets, is considered necessary for shareholders, investors, analysts and corporate executives. P/E is used as an important indicator in investment decisions. In this research, harmony search metaheuristic algorithm is used to select optimal variables affecting P/E and then, modelling is done through multivariate regression based on panel data. For this purpose, a sample of 87 companies has been selected from listed companies in the Tehran Stock Exchange during a 10-year period (2006-2015). The results indicate the effect of the variables of stock returns, stock price to book value ratio, price to net selling ratio, return on assets, earnings per share, market value to book value, money volume, operating return margin, return on capital, and current assets, as top ten variables, on P/E ratio, which estimates a total of 86% of the P/E ratio changes.

This paper presents a mathematical model for cell formation, cell layout, and resources assignment problems simultaneously. This model focuses on the influence of the man-machine relationship aspect on the cellular manufacturing system (CMS) design. The main purpose of the model is to demonstrate how to design the CMS with the new aspect such that the costs associated with processing, layout, worker, and machine idle time, machine and tool are minimized. The proposed model is applied to a numerical example using Lingo software. Due to the complexity of the presented model, a genetic algorithm (GA) is employed to find satisfactory solutions. To verify the solutions, a harmony search (HS) algorithm is used. Additionally, the Taguchi method is utilized to adjust the parameters in two proposed algorithms. Finally, to validate the model, some numerical examples are presented. Results emanating from the research show that the proposed HS algorithm is a favorable method for the presented model.