6.º a 8.º gradoProbability & StatisticsLección disponible
Probability
Probability as a number from 0 to 1, sample spaces of equally likely outcomes, experimental (relative frequency) versus theoretical probability, and simulation.
math.prob.probability-intro
Se basa en
Requisitos previos obligatorios, hasta el fondo: 6
Aprenderás a
- List sample spaces for simple experiments, using tables or tree diagrams for two stages.
- Compute probabilities of events with equally likely outcomes as fractions.
- Compare theoretical probabilities with relative frequencies from repeated trials or simulations.
Definición
- A sample space is the set of possible outcomes of an experiment; an event is a subset of the sample space.
- If all outcomes in a finite sample space S are equally likely, the probability of an event A is P(A) = |A|/|S|.
- The relative frequency of an event in n trials is the number of times it occurred divided by n.
Teorema
- 0 ≤ P(A) ≤ 1, P(S) = 1, and P(not A) = 1 − P(A).
- As the number of independent trials grows, relative frequencies tend to settle near the probability (the law of large numbers, stated informally).
Errores frecuentes
- The gambler's fallacy: thinking a fair coin is 'due' to land heads after several tails.
- Assuming all outcomes are equally likely, for example all sums of two dice.
- Believing a probability of 1/6 means the event happens exactly once in every 6 trials.
Conduce a
Descubrimientos opcionales
- Measure-theoretic probability Kolmogorov (1933) placed probability on the foundation of measure theory.
- Markov chains A walker tosses a fair coin every minute: heads, one step east; tails, one step west. Is she certain to come back to where she started? What if she can also step north and south — or up and down in space?Sendero del Asombro →
- ← Ratios, rates and proportional reasoning
- ← Counting principles