Analyze the properties of 'Baumol-Tobin Model' of cash management regarding the transactions demand for money. How does the demand for money respond to changes in the interest rate?

💡 Solution & Explanation

The Baumol-Tobin Model applies inventory theory to individual cash management, showing that the transactions demand for money varies inversely with the interest rate and is a square root function of income. Individuals hold cash for transactions but incur an opportunity cost in forgone interest by not keeping funds in interest-bearing assets, while facing brokerage fees or transaction costs every time they convert bonds to cash. When interest rates rise, the opportunity cost of holding cash increases, prompting individuals to make more frequent, smaller trips to the bank and hold lower average cash balances. This microfounded approach demonstrates that money demand exhibits economies of scale with respect to income. A related monetary concept is Keynes's speculative motive for holding money, which also links asset choices to interest rates.