Chapter 1 · Interactive Examples

Basic Probability Examples

This is the practice lab for the main probability lesson. The theory page now carries the chapter logic, while this page keeps the intuition-first explanations and animated dental simulations that make the ideas easier to feel.

Quick refresher

The earlier intuition-first content now lives here

Before you simulate, use these three ideas as your mental map. Then scroll into the dental examples and watch each concept update live with animation.

Chance events

Probability runs from 0 to 1. As more implant outcomes are simulated, the observed success rate settles near the true value.

Expected value

The expected value is a weighted average. In the DMFT example, it acts like the long-run center of the score distribution.

Variance

Variance describes spread. Two clinics can have similar averages but very different consistency, which matters for interpretation.

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Dental Implant Success Simulator

Probability is a number between 0 and 1 indicating how likely an event will occur. In dentistry, implant procedures, root canals, and fillings each carry specific success rates backed by clinical research.

Will this implant integrate successfully? Will a root canal relieve the patient's pain? These are questions of probability. By simulating many outcomes, we observe the Law of Large Numbers in action.

0 ≤ P(A) ≤ 1   ·   P(Aᶜ) = 1 − P(A)

Open the implant probability simulator

Try preset success rates, change the probability slider, and watch the observed rate move closer to the true value as more patients are simulated.

Clinical Scenarios
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Observed P
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DMFT Score Distribution

The expected value (mean) is the long-run average of outcomes, weighted by their probabilities. The DMFT index tracks Decayed, Missing, and Filled Teeth — a key measure in dental epidemiology.

Different populations show different DMFT distributions. A healthy group clusters near 0, while a high-risk group skews toward higher scores.

E[X] = Σ x · P(x)

Explore expected value with DMFT scores

Open the simulator to choose a population, reshape the DMFT probabilities, and watch the running sample mean stabilize around the true expected value.

Population Presets

Drag the bars below to customize DMFT score probabilities, or select a preset. Then roll to see the sample mean converge to E[X].

DMFT Score Distribution
True E[X]
Sample Mean
Rolls
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Last Score
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Patient Satisfaction Scores

Variance measures how spread out outcomes are from the expected value. In dentistry, patient satisfaction varies widely — some patients report excellent outcomes, others experience complications.

A low variance means consistent satisfaction; high variance signals unpredictable results. Understanding this spread is crucial for informed consent and treatment planning.

Var(X) = E[(X − E[X])²]

Test how spread changes from one score setup to another

Launch the simulator to include or remove satisfaction scores, then draw repeated samples and compare the running variance with the true variance.

Outcome Scenarios

Toggle scores to include/exclude them from the population. Each score (1–10) represents a patient satisfaction rating. Draw samples and watch variance converge.

Satisfaction Scores (click to toggle)
True Var(X)
Running Var
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Last Score
Simulating Dental Implant Outcomes
🦷 Success
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Failure
Distance from true P:
Rolling DMFT Distribution
? DMFT
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Sample Mean
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Drawing Patient Satisfaction Scores
? Score
True Var(X)
Running Var
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