To derive the linear pricing equations, you impose the no-arbitrage condition that the current price of each traded asset must equal the sum of its state-contingent payoffs weighted by the corresponding state prices. This produces one linear equation per traded asset, with the state prices acting as the unknowns.
Conditions: One-period model with a finite set of states.; Prices of all traded assets are known today.; State-contingent payoffs for each asset are known.; The unknowns are the state prices (Arrow-Debreu security prices).
To derive the linear pricing equations, you impose the no-arbitrage condition that the current price of each traded asset must equal the sum of its state-contingent payoffs weighted by the corresponding state prices. This produces one linear equation per traded asset, with the state prices acting as the unknowns.
Conditions: One-period model with a finite set of states.; Prices of all traded assets are known today.; State-contingent payoffs for each asset are known.; The unknowns are the state prices (Arrow-Debreu security prices).
The solution for the state price vector is unique because the coefficient matrix of the resulting linear pricing system has a nonzero determinant. A nonzero determinant guarantees that the system of linear equations has exactly one unique solution for the unknown state prices.
Conditions: The market model has three states and three traded assets.; The pricing system is a 3x3 linear system.; The coefficient matrix of the system is nonsingular (determinant is nonzero).
The solution for the state price vector is unique because the coefficient matrix of the resulting linear pricing system has a nonzero determinant. A nonzero determinant guarantees that the system of linear equations has exactly one unique solution for the unknown state prices.
Conditions: The market model has three states and three traded assets.; The pricing system is a 3x3 linear system.; The coefficient matrix of the system is nonsingular (determinant is nonzero).
The bank account contributes 110 in every state because it is a risk-free asset that pays 10% interest per year. Investing 100 today guarantees a return of 110 at time one, regardless of which of the three possible scenarios occurs.
Conditions: The bank account is risk-free.; The bank account pays 10% interest per year.; The initial investment (current price) is 100.; The model is a one-period setting with multiple states.
The bank account contributes 110 in every state because it is a risk-free asset that pays 10% interest per year. Investing 100 today guarantees a return of 110 at time one, regardless of which of the three possible scenarios occurs.
Conditions: The bank account is risk-free.; The bank account pays 10% interest per year.; The initial investment (current price) is 100.; The model is a one-period setting with multiple states.
An Arrow-Debreu security is a theoretical financial instrument that pays exactly 1 unit of currency in one specific state of the world and 0 in all other states. The state price vector is the collection of the current prices of all such Arrow-Debreu securities for the finite set of states in the market model.
Conditions: The market model has a finite set of states.; Payoffs are normalized to 1 in one state and 0 elsewhere.; The model is a one-period setting.
An Arrow-Debreu security is a theoretical financial instrument that pays exactly 1 unit of currency in one specific state of the world and 0 in all other states. The state price vector is the collection of the current prices of all such Arrow-Debreu securities for the finite set of states in the market model.
Conditions: The market model has a finite set of states.; Payoffs are normalized to 1 in one state and 0 elsewhere.; The model is a one-period setting.