This paper examines the degree to which cash flow availability influences firm investment in six OECD countries. In particular, we are interested in the extent to which the reliance on internal funds is affected by firm size, since there is general agreement that smaller firms have less access to external capital markets and, thus, should be more affected by the availability of internal funds. Earlier work has concluded that the documented positive relationship between cash flow and investment is evidence of the existence of financial constraints. We first examine all firms, regardless of size, in each country, and we find that the amount of corporate investment is affected by internal resources in all six countries; that is, internal financing affects firm investment. We then repeat the analysis segmenting the sample using three measures of firm size. Contrary to our a priori expectations, we find that the cash flow-investment sensitivity is generally highest in the large firm size group and smallest in the small firm size group. We deduce that the explanations for these findings are grounded in managerial agency considerations, and in the greater flexibility enjoyed by large firms in timing their investments. Thus, we conclude that the degree of sensitivity of a firm's investments to its cash flows cannot be interpreted as an accurate measure of its access to capital markets (as do Kaplan, S., Zingales, L., 1997. The Quarterly Journal of Economics 169–215), since small firms are known to have less access to external markets.

We find that option listings are associated with a decrease in the variance of the pricing error, a decrease in the adverse selection component of the spread, and an increase in the relative weight placed by the specialist on public information in revising prices for the underlying stocks. We also find that there is a decrease in the spread and increases in quoted depth, trading volume, trading frequency, and transaction size after option listings. Overall, our results suggest that option listings improve the market quality of the underlying stocks.