Effects of Different Definitions of Firm Size on Ranking and Goodness of Fit in Causal Liquidity Model

Firm size generally has been used as a control variable in positive accounting and finance researches. Firm size can be measured by several indicators such as book value of assets, market value of company (or sum of share and total liabilities values), value of sales and number of employees. In this study the effects of using different definitions of firm size on ranking of firms (for an assumed definition of size), and on goodness of fit in the liquidity forecasting model (the ratio of operating cash flows to sales) were inspected, using a sample of 120 manufacturing companies listed in the Tehran Stock Exchange, in the years 2006 to 2012. The result showed that ranking of the companies with regard to different definitions does not change in response to firm size, significantly. But, in the operational liquidity forecasting model, the definition of firm size in terms of sales value, in both the logarithmic and relative value scales, has the lowest forecasting error