Random subgroups of linear groups are free

We show that on an arbitrary finitely generated non virtually solvable linear group, any two independent random walks will eventually generate a free subgroup. In fact, this will hold for an exponential number of independent random walks.Comment: 37 page

The Causal Relationship between Capital Structure and Cost of Capital: Evidence from ICT Companies Listed at NASDAQ

In this study, we intend to examine the Information and Communication Technology (ICT) firms, from a financial perspective. The causal relationship between capital structure and cost of capital is investigated in a simultaneous equation framework. On the one hand, we relate international diversification to the firm’s capital structure, and on the other, we test their individual and collective inferences on the combined debt and equity cost of capital. Even though ICT companies are subject to the same market forces as other firms, the rapid development of the industry, complexity of their technologies and presence of the network effect may have valuable implications in determining their financing patterns. Using information pertaining to ICT and non-ICT firms listed on the NASDAQ stock exchange, we expect a negative correlation between international diversification and higher total and long-term debt ratios, and a reduction in the overall cost of capital. Results suggest significant heterogeneity among ICT and non-ICT firms and within each group by a number of firm characteristics.International diversification; Capital structure; Cost of capital; Debt; ICT; NASDAQ

Dynamics of Capital Structure: The Case of Korean Listed Manufacturing Companies

firms is developed in this paper and results compared with the classical static model. This paper specifies and estimates the unobservable optimal capital structure using a wide range of observable determinants. Uunbalanced panel data of Korean listed firms for the period 1985 to 2002 is used in this study. In addition to identification and estimation of the effects of the determinants of capital structure and capital structure optimality, some Korea-specific features such as the structural break before and after the financial crisis, as well as affiliation to a chaebol business groups, are taken into account to verify whether the optimal capital structure was affected by the financial crisis or whether belonging to a chaebol has any effect, and if so, to what extent.Capital structure; debt; firm; panel data; adjustment; Korea

Investigation of nucleation and crystal growth kinetics of nickel manganese oxalates

The nucleation and the crystal growth rates of mixed nickel manganese oxalates have been determined from the changes of the ionic concentration of the solution and the crystal size distribution during the precipitation process within a supersaturation range 0–0.1 M. Thermodynamic solubility calculations have been used to identify the different species contributing the precipitation reaction and for estimation of the thermodynamic constant. Experimental data show that the nucleation rate of mixed nickel manganese oxalate in this supersaturation range is consistent with a primary heterogeneous mechanism and was found to obey to an exponential law. The crystal growth rates indicate a surface-integration-controlled mechanism with a first-order law with respect to the supersaturation