Arbitrage is a widely used trading strategy of simultaneously purchasing and selling the same asset in different exchanges. It takes advantage of the differences in the asset's listed price in different markets to earn a risk-free profit. Traders who use this strategy are called arbitrageurs.
Arbitrage is closely related to the market efficiency theory. Arbitrage exists as a result of market inefficiencies. If markets are perfectly efficient, all equivalent assets should converge to the same price. However, it is not always the case in reality, and the mispricing of assets creates arbitrage opportunities for investors.
Currency arbitrage allows traders to make a profit from the difference in exchange rates offered by brokers in different currency markets for the same pair of currencies.
Interest rates vary between countries, creating an opportunity for investors to profit from the difference by investing in higher-yielding currencies. Investors can hedge the currency exchange risk with forward contracts.
A carry trade involves converting borrowed low-interest rate currency into another high-interest rate currency to generate profit.
Cash-and-carry arbitrage seeks to exploit the pricing discrepancies of an asset between the spot and futures markets. Investors will take a long position on a security while simultaneously taking a short position on a futures contract.
Statistical arbitrage is a short-term trading technique that involves using complex statistical models to identify trading opportunities and profit from price differences. This strategy is considered deeply quantitative and usually uses mean reversion models that require significant computational power.