Kapali Edu — Prediction markets, explained

Learn to read the market before you take a side.

A structured, open curriculum on probability, pricing and risk. Written for people who want to understand prediction markets — not gamble on them.

24
Lessons
6
Modules
Free
Always

Module 01

What a prediction market actually is

A market where contracts settle at 1 or 0 depending on a real-world outcome. Price is not a vibe — it is the crowd's live estimate of a probability, weighted by how much money is willing to stand behind it.

  • Contracts, settlement and resolution sources
  • Why 62¢ means roughly a 62% implied chance
  • Order books vs. automated market makers

Module 02

Reading price as probability

Converting cents to probability is the easy part. The skill is knowing when the price is wrong — thin liquidity, stale news, or a resolution rule that nobody read carefully.

  • Implied odds, fees and the true break-even
  • Bid-ask spread as a confidence interval
  • Where mispricings actually come from

Module 03

Building a view

A position should start with a number you wrote down before you looked at the market. Base rates first, headlines second.

  • Base rates and reference classes
  • Bayesian updating on real news
  • Separating signal from narrative

Module 04

Sizing and bankroll

Most people are not wrong about direction. They are wrong about size. Edge without sizing discipline converges to zero.

  • Expected value in plain arithmetic
  • Fractional Kelly and why full Kelly hurts
  • Correlation across positions you thought were independent

Module 05

Resolution risk

The most expensive losses are not wrong forecasts. They are correct forecasts that resolved against you on a technicality.

  • Reading the rules before the chart
  • Ambiguous wording and edge cases
  • Oracle, dispute and settlement timelines

Module 06

Playing responsibly

Prediction markets are a forecasting tool that happens to involve money. Treat capital you cannot lose as off-limits — permanently.

  • Loss limits, cool-downs and session caps
  • Recognising tilt and chase behaviour
  • When to close the tab and get help

Field notes

Short notes. One idea each.

The working notebook behind the curriculum — published as we write it, revised as we learn.

Note 0014 min

Price is a probability, not a prediction

A contract at 70¢ does not say the event will happen. It says that across many identical markets priced at 70¢, roughly seven in ten resolve YES. Calibration is judged over hundreds of trades, never one.

Read note
Note 0026 min

Your break-even is worse than the price

Fees, spread and slippage all move the line you actually need to beat. Compute the true break-even before the trade, and refuse anything where your edge is thinner than the friction.

Read note
Note 0035 min

Write the number before you look

Anchoring is the cheapest way to lose. Estimate the probability from base rates first, then open the market. If your number and the market's number are close, there is no trade — and that is a result.

Read note
Note 0047 min

Thin markets lie loudly

A 20¢ move on $40 of volume is noise wearing a costume. Check depth and recent volume before treating a price as information about the world.

Read note
Note 0055 min

Read the resolution rules twice

Most disputed outcomes were never ambiguous in the data — only in the wording. Know the source, the cutoff time and the tiebreaker before you size anything.

Read note
Note 0063 min

Size so that being wrong is boring

If a losing position changes your mood, your week or your plans, the position was too large. Fractional sizing keeps you in the game long enough for edge to show up.

Read note

Glossary

The vocabulary.

Eight terms carry most of the meaning. Learn these and the rest of the market reads itself.

Contract
A binary claim that settles at $1 if the event happens and $0 if it does not.
Implied probability
The contract price read as a percentage — 43¢ implies about a 43% chance.
Spread
The gap between the best bid and best ask. Wide spreads mean uncertainty and cost.
Liquidity
How much size the market can absorb before the price moves against you.
Resolution source
The named authority whose data decides the outcome. Read it before trading.
Base rate
How often this kind of event has happened historically, before any news.
Calibration
Whether your 70% forecasts actually come true about 70% of the time.
Kelly fraction
A sizing rule tied to your edge. Most traders should use a fraction of it.

Responsible play

Forecasting is the point. Risk is the cost.

01

Set the limit before the session

Decide the maximum you are willing to lose today, in advance and in writing. A limit invented mid-session is not a limit.

02

Never trade borrowed or needed money

Rent, tuition, debt and emergency savings are not risk capital. There is no forecast good enough to justify them.

03

Chasing is the tell

Increasing size after a loss to get even is not a strategy — it is the single most reliable predictor of a bad outcome.

04

Take scheduled breaks

Fatigue degrades judgement long before it feels like it. Close the tab on a timer, not on a feeling.

If it stops being a choice

If trading is affecting your sleep, your finances or your relationships, stop and talk to someone. Support is free and confidential — contact a local problem-gambling helpline, or reach the National Council on Problem Gambling at 1-800-522-4700 in the US.