Probability Laboratory

The Monty Hall
Paradox Explained.

MONTYLAB is a digital observatory for probability. Test your intuition against the math, simulate N-door scenarios, and master the logic behind the switch.

1.2M+Active TrialsSimulated Runs
99.9%Win AccuracySwitch Strategy
4-StageLogic DepthPólya Heuristic
SIM // LIVE ENGINE
N-DOOR MODE
Interactive Monty Hall door simulation interface
P = 1/N
00:00:00
MH

Monty Hall Logic Engine

Probability & Heuristics

Verified

Join thousands of students using our simulator to visualize the counter-intuitive nature of conditional probability.

Core Probability Rules

Mastering the Paradox

Unifying mathematical rigor with interactive simulations to dismantle cognitive probability illusions.

Logic Proof
PROBABILITY THEORY
The Switch Advantage
Switching doors increases your win probability from 1/N to (N-1)/N, as the host reveals all losing options.
Switch StrategyP = (N-1)/N
Switch Win99% Chance
Stay Win1% Chance
Heuristic
PROBLEM SOLVING
Pólya Heuristic Method
Apply the four-stage framework: understand, devise a plan, carry out the plan, and look back at the result.
4-STAGE PLANLogical Rigor
Verified
Heuristic DepthHigh (4/4)
Simulator
INTERACTIVE ENGINE
N-Door Simulator
Configure door counts from 3 to 100 and observe how the probability shifts in real-time simulations.
Door Config100 Max
Archive
ARCHIVAL CONTEXT
Paradoxical Origins
Explore the history of the Monty Hall problem, from its game show roots to the 1990 media firestorm.
Historical Data
Paradox Age50+ Years

Run your own probability trials

Test the switch strategy against thousands of simulated door scenarios.

PROBABILITY MATRIX

Stay vs Switch

In a 100-door scenario, the choice to switch is mathematically superior. Compare the win rates and see why switching leverages host data to maximize your prize probability.

Stay StrategyRisk: High
Static Choice
Sticking to your initial door choice ignores the host's reveal, leaving you with the original 1/100 probability.
Win Probability (Stay)1.0%
1%

Initial choice accuracy

Prize ExposureLow
10%

Host reveals 98 goats

Risk FactorHigh
99%

Sticking to 1/100 odds

Outcome BiasFixed
90%

Ignoring host data

Switch StrategyOptimal Gain
Adaptive Choice
Switching doors incorporates the host's knowledge, shifting the probability to 99/100 in your favor.
Win Probability (Switch)99.0%
99%

Optimal strategy gain

Prize ExposureHigh
99%

Host reveals 98 goats

Risk FactorLow
1%

Leveraging host info

Outcome BiasDynamic
10%

Using host data set

Probability Matrix

Detailed comparison of outcomes based on strategy.

MetricStaySwitchAdvantage
Win Rate (100 Doors)
Probability
1.0%99.0%99x higher
Loss Rate (100 Doors)
Probability
99.0%1.0%99% reduction
Host Information
Logic
Ignored (Stay)Utilized (Switch)Data-driven
Pólya Heuristic
Strategy
GuessingSystematicProven path
Prize Certainty
Outcome
Low confidenceHigh confidenceNear-certain
Decision Model
Strategy
Static choiceAdaptive choiceOptimal gain
SIMULATE YOUR OWN ODDS

Test the theory yourself.

Run thousands of trials in our simulator to see the law of large numbers in action.

PÓLYA HEURISTIC

Solving the Paradox in Four Steps

George Pólya’s framework provides the logical rigor needed to dismantle the Monty Hall illusion through systematic analysis and empirical verification.

01Phase One

Define the Paradox

Understand the Problem
Identify the core variables: the total doors, the prize location, and the host's specific knowledge of the doors.
Logic GateP = 1/N
Variables defined
Identify knowns & unknowns
02Phase Two

Model the Sample Space

Devise a Plan
Map out all possible outcomes for staying versus switching to determine the conditional probability of winning.
tree_diagram.svg100%
Sample SpaceMapped
Construct probability tree
03Phase Three

Execute the Simulation

Carry Out the Plan
Run thousands of trials to observe how the empirical win rate converges toward the theoretical probability.
Trial Data10k Runs
Stay StrategySwitch Strategy100 Doors3 Doors
Compute trial outcomes
04Phase Four

Verify the Solution

Look Back
Review the results to ensure the logic holds across varying door counts and confirms the switch advantage.
VerifiedP = 99%
HeuristicConfirmed
Validate the heuristic

Test the Theory Yourself

Apply the four-step method in our interactive simulator to see how probability shifts when you switch doors.

Historical Paradox Archive

The 1990 Controversy

A look back at the famous column that challenged thousands of experts and redefined our understanding of probability.

Monty Hall standing in front of three numbered doors
1975
Game Show Debut
The Monty Hall Show
Let's Make a Deal Origins

Monty Hall hosts the iconic game show where contestants choose between three doors, unknowingly setting the stage for a future mathematical firestorm.

Odds3 Doors
Result1 Prize
Source1 Host
Marilyn vos Savant's Parade magazine column clipping
1990
Parade Column
The Vos Savant Paradox
Marilyn's Famous Solution

Marilyn vos Savant publishes the correct solution in Parade, asserting that switching doors doubles your probability of winning the prize.

Odds1/3 to 2/3
ResultSwitch Win
Source1 Column
Newspaper headlines showing mathematical debate
1991
Academic Backlash
The PhD Mathematicians
Thousands Claimed She Was Wrong

Over 1,000 PhDs wrote to Parade claiming Marilyn was incorrect, highlighting the deep-seated human cognitive bias against conditional probability.

Odds1000+ Letters
ResultPhD Error
SourceMath Experts
Diagram illustrating Pólya's four-step problem solving method
2000
Pólya Heuristic
Pólya's Four Stages
Solving via Heuristic Framework

Applying George Pólya's method: Understand the problem, devise a plan, carry out the plan, and look back to verify the probability logic.

Odds4 Stages
ResultLogic Path
SourceG. Pólya
Visualization of 100 doors with one prize highlighted
2018
N-Door Simulation
The 100-Door Proof
Scaling the Paradox to 100

With 100 doors, the host opens 98, leaving 2. Switching yields a 99% win rate, proving the logic holds regardless of the number of doors.

Odds99% Win Rate
Result100 Doors
SourceSimulation
Modern digital laboratory interface for probability testing
2024
Digital Lab
MontyLab Observatory
Dismantling Cognitive Illusions

We continue to explore probability through interactive simulations, archival exposition, and rigorous mathematical heuristic frameworks.

OddsLive Data
ResultReal-time
SourceCommunity

Master the probability logic

Explore our interactive simulator to test the Monty Hall problem yourself and see the math in action.

Mathematical Observatory

Test your intuition against reality

Dismantle cognitive illusions with our interactive simulator. Experience the Monty Hall paradox through rigorous computation and historical analysis.

N-Door Logic

Configure your simulation with any number of doors to test probability.

Pólya's Method

Understand the paradox through the four-stage heuristic framework.

Historical Roots

Explore the origins of the problem and its impact on statistics.

Live Simulator

Run thousands of trials to see the Law of Large Numbers in action.

Ready to run a trial?

Launch the simulator to see if switching doors truly increases your odds of winning.

Empirical probability engine • Based on the Monty Hall paradox