Introduction to Options
Pricing and Hedging Derivative Securities - Back, Loewenstein, and Liu
What Are Derivatives?
Derivative securities are financial instruments whose values are derived from an underlying asset, index, or rate.
- Underlying assets can be:
- Stocks, bonds, commodities
- Currencies, interest rates
- Market indices
- Value fluctuates based on changes in the underlying
- Used for hedging risks and speculation
Trading Venues
Exchange-Traded
- Traded on regulated exchanges (CME, NYSE, ICE)
- Standardized contracts
- Centralized clearing
- Price transparency
- High liquidity
Over-the-Counter (OTC)
- Private bilateral contracts
- Customizable terms
- Higher counterparty risk
- Less transparency
- Tailored solutions
Options
For the remainder of this lecture, we’ll focus on options - the most versatile derivatives.
- Call option: Right to buy an asset at a fixed price (the strike)
- Put option: Right to sell an asset at a fixed price (the strike)
The buyer pays the seller a premium upfront for this right.
Options are particularly important for several reasons:
- Widely traded: Billions of contracts annually across global exchanges
- Versatile: Can be used for speculation, hedging, or income generation
- Building blocks: Understanding options helps with other derivatives
Option Basics: Key Terminology
- Premium: Price paid to buy the option
- Strike Price (K): Fixed price at which option can be exercised
- Expiration Date: When the contract ends
- Exercise: Using the right granted by the option
- Underlying Asset: The financial instrument the option is based on
American vs. European Options
Despite the names, both trade worldwide!
American Options
- Can be exercised any time before expiration
- More flexibility
- More common on exchanges
- Slightly more expensive
European Options
- Can only be exercised at expiration
- Less flexibility
- Simpler to price
- Common in indices and OTC contracts
Rights, Obligations, and Motivations
Option Buyers (Long)
- Pay premium upfront
- Have rights, no obligations
- Choose whether to exercise
- Max loss = premium paid
- Motivations:
- Speculation with leverage
- Hedging/insurance
Option Sellers (Short)
- Receive premium upfront
- Have obligations
- Must fulfill if exercised
- Potentially unlimited losses
- Motivation:
Interactive Market Data
Let’s explore real option prices:
Patterns in Option Prices: Strike Effects
Experimenting with the market data reveals consistent patterns:
Call Options:
- Prices decrease as strike prices increase
- Call with strike $50 > Call with strike $100
- Why? Lower strike = more valuable right to buy
Put Options:
- Prices increase as strike prices increase
- Put with strike $100 > Put with strike $50
- Why? Higher strike = more valuable right to sell
Patterns in Option Prices: Time Effects
Time to expiration matters:
- Longer-dated options cost more than shorter-dated options
- Why?
- More time for favorable price movements
- Greater flexibility (American options)
- Higher uncertainty
This pattern holds for both calls and puts,
Intrinsic Value
Intrinsic value = What the option is worth if exercised immediately (or at expiration)
Call Option:
\[\text{Intrinsic Value} = \max(S - K, 0)\]
- If \(S = \$50\), \(K = \$40\)
- Intrinsic value = \(\$10\)
- Can buy at \(\$40\), sell at \(\$50\)
Put Option:
\[\text{Intrinsic Value} = \max(K - S, 0)\]
- If \(S = \$50\), \(K = \$60\)
- Intrinsic value = \(\$10\)
- Can buy at \(\$50\), sell at \(\$60\)
Moneyness: ITM, ATM, OTM
Options are classified by their relationship to the current price:
| In the Money (ITM) |
\(S > K\) |
\(S < K\) |
| At the Money (ATM) |
\(S \approx K\) |
\(S \approx K\) |
| Out of the Money (OTM) |
\(S < K\) |
\(S > K\) |
- ITM: Positive intrinsic value
- ATM/OTM: Zero intrinsic value
Time Value and Time Decay
Time value = Option price - Intrinsic value
- Options are usually worth more than intrinsic value before expiration
- Why? Potential for favorable price movements
- Time decay: Time value decreases as expiration approaches
- At expiration: Time value = 0, Option value = Intrinsic value
American options are always worth at least their intrinsic value (otherwise arbitrage!)
Key Insights About Options
Options differ fundamentally from other financial instruments:
- Non-linear payoffs: Not just multiples of the underlying
- Asymmetric risk/reward: Different for buyers vs. sellers
- Time decay: Value erodes as expiration approaches
- Volatility sensitivity: Option prices increase with uncertainty
- Multiple dimensions: Price, time, volatility all matter
These properties make options powerful but complex!
Trading Options on Exchanges
Most options are traded on organized exchanges:
- Standardized contracts: Fixed strikes and expirations
- Transparent pricing: Public order books
- Clearinghouse guarantee: Eliminates counterparty risk
- Most positions closed before expiration: Through offsetting trades rather than exercise
Strikes and Maturities
Exchanges determine which options are available:
- Strike prices: Added to bracket the current market price
- New strikes introduced as underlying price moves
- Typically spaced at regular intervals
- Expiration dates:
- Weekly, monthly, and quarterly options
- New expirations added as older ones expire
- Availability depends on trading interest
Open Interest and Contract Creation
Unlike stocks, options have no pre-existing supply:
- Long position: Option buyer
- Short position: Option seller
- Open Interest: Total number of long (= short) positions
How open interest changes:
- New buyer + New seller → Open interest increases
- Existing buyer sells to new buyer → Open interest unchanged
- Existing buyer and seller both close → Open interest decreases
Volume and Open Interest Patterns
Understanding trading patterns:
Concentration Near Current Price:
- Volume/open interest highest within 10-20% of current price
- Far OTM options trade infrequently
- Wider bid-ask spreads for less popular strikes
Popularity of OTM Options:
- Lower cost → higher leverage
- Attractive for speculation (large % returns possible)
- Used for tail risk hedging (portfolio insurance)
The Life Cycle of Open Interest
Open interest evolves over an option’s life:
Initial Growth:
- Starts at zero for new series
- Grows as traders discover it
- Peaks when several weeks/months remain
Example:
- Day 1: Trader A buys 10 calls from Trader B → OI = 10
- Day 2: Trader C buys 5 from Trader D → OI = 15
- Day 3: Trader E buys 3 from Trader A → OI = 15 (unchanged)
Decline Phase:
- Decreases as expiration approaches
- Traders close positions
- Risk managers avoid near-expiry options
Final Settlement:
- ITM options: auto-exercised
- OTM options: expire worthless
Payoff vs. Profit Diagrams
Two important ways to visualize options:
Payoff Diagram
- Shows intrinsic value at expiration
- Function of underlying price \(S\)
- Ignores premium paid/received
Profit Diagram
- Shows actual profit/loss if held to expiration
- Payoff minus premium paid
- Or payoff plus premium received
Long Call: Payoff and Profit
Buying a call option (bullish strategy):
Long Call: Key Characteristics
Market View: Bullish (expect price to rise)
Maximum Profit: Unlimited (as \(S\) increases)
Maximum Loss: Premium paid ($5 in example)
Breakeven: Strike + Premium = $105
Best for: Speculating on upside with limited downside risk
Long Put: Payoff and Profit
Buying a put option (bearish strategy):
Long Put: Key Characteristics
Market View: Bearish (expect price to fall)
Maximum Profit: Strike - Premium = $95 (limited by \(S \geq 0\))
Maximum Loss: Premium paid ($5)
Breakeven: Strike - Premium = $95
Best for: Portfolio insurance, speculating on downside with limited risk
Short Call: Payoff and Profit
Writing (selling) a call option:
Short Call: Key Characteristics
Market View: Neutral to bearish (expect price to stay flat or fall)
Maximum Profit: Premium received ($5)
Maximum Loss: Unlimited (as \(S\) increases)
Breakeven: Strike + Premium = $105
Risk: Very high! Limited upside, unlimited downside
Short Put: Payoff and Profit
Writing (selling) a put option:
Short Put: Key Characteristics
Market View: Neutral to bullish (expect price to stay flat or rise)
Maximum Profit: Premium received ($5)
Maximum Loss: Strike - Premium = $95 (if \(S \to 0\))
Breakeven: Strike - Premium = $95
Use case: Collect premium while willing to buy stock at strike price
Summary of Basic Option Positions
| Long Call |
Bullish |
Unlimited |
Premium |
\(K +\) Premium |
| Long Put |
Bearish |
\(K -\) Premium |
Premium |
\(K -\) Premium |
| Short Call |
Bearish |
Premium |
Unlimited |
\(K +\) Premium |
| Short Put |
Bullish |
Premium |
\(K -\) Premium |
\(K -\) Premium |
These four positions are the building blocks for all option strategies!
Comparing Long vs. Short Positions
Long Positions (Buyers)
- Pay premium upfront
- Limited downside (premium)
- Potentially large upside
- Time decay works against you
- Benefit from volatility
Short Positions (Sellers)
- Receive premium upfront
- Limited upside (premium)
- Potentially large downside
- Time decay works for you
- Hurt by volatility
Next Steps in Options
Building on today’s foundation, we’ll explore:
- Option portfolios: Protective puts, covered calls, spreads, straddles
- Option pricing models: Black-Scholes formula, binomial trees
- Greeks and sensitivity analysis: How option values change with inputs
- Volatility: Historical vs. implied, volatility surfaces
- Hedging strategies: Delta hedging, portfolio insurance