utils.stats.get_sample_size
utils.stats.get_sample_size(alpha, beta, sigma, delta)Calculate sample size n for comparing two means.
Formula: n = 2 * sigma^2 * (z_{1-alpha/2} + z_{1-beta})^2 / delta^2 This corresponds to a two-sided test with equal variance.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
| alpha | float | Significance level (Type I error probability). | required |
| beta | float | Type II error probability (1 - Power). | required |
| sigma | float | Standard deviation of the population (assumed equal for both groups). | required |
| delta | float | Minimum detectable difference (effect size to detect). | required |
Returns
| Name | Type | Description |
|---|---|---|
| float | float | The required sample size n per group. |
Examples
>>> from spotoptim.utils.stats import get_sample_size
>>> alpha = 0.05
>>> beta = 0.2 # Power = 80%
>>> sigma = 1.0
>>> delta = 1.0
>>> n = get_sample_size(alpha, beta, sigma, delta)
>>> print(f"{n:.4f}")
15.6978