Sample Proportion Formula:
From: | To: |
The sample proportion (p̂) represents the fraction of successes in a sample. It's a fundamental statistic used to estimate the true population proportion when complete enumeration isn't possible.
The calculator uses the sample proportion formula:
Where:
Explanation: The formula simply divides the count of successes by the total number of trials or observations.
Details: The sample proportion is crucial for statistical inference, particularly in constructing confidence intervals and hypothesis testing for population proportions.
Tips: Enter the number of successes (x) and total sample size (n). x must be non-negative and ≤ n, while n must be positive.
Q1: What's the difference between p and p̂?
A: p represents the true population proportion (unknown), while p̂ is the sample estimate of p.
Q2: What makes a good sample proportion estimate?
A: A good estimate comes from a representative, random sample with adequate sample size (n).
Q3: When is the sample proportion formula used?
A: Commonly used in surveys, quality control, medical trials, and any scenario involving binary outcomes.
Q4: What are common mistakes with p̂?
A: Using non-random samples, small sample sizes, or confusing counts with proportions.
Q5: How is p̂ related to the binomial distribution?
A: p̂ is the maximum likelihood estimator of the binomial probability parameter p.