Class ChiSquareTest

java.lang.Object
cloud.opencode.base.math.stats.inference.ChiSquareTest
public final class ChiSquareTest extends Object
Chi-squared test implementations for hypothesis testing. 卡方检验实现，用于假设检验

Provides goodness-of-fit and independence tests. All methods return a TestResult with p-values computed from the chi-squared distribution.

提供拟合优度检验和独立性检验。 所有方法返回从卡方分布计算 p 值的 TestResult。

All methods are stateless and thread-safe.

所有方法无状态且线程安全。

Since:
JDK 25, opencode-base-math V1.0.3
Author:
Leon Soo www.LeonSoo.com
See Also:

  • Method Details

    • goodnessOfFit

      public static TestResult goodnessOfFit(double[] observed, double[] expected)
      Performs a chi-squared goodness-of-fit test. 执行卡方拟合优度检验

      Tests whether observed frequencies differ significantly from expected frequencies. Statistic = sum((O - E)^2 / E), df = k - 1.

      检验观察频率与期望频率是否存在显著差异。 统计量 = sum((O - E)^2 / E)，df = k - 1。

      Parameters:
      observed - the observed frequencies (must all be non-negative) / 观察频率（必须全部非负）
      expected - the expected frequencies (must all be positive) / 期望频率（必须全部为正）
      Returns:
      the test result / 检验结果
      Throws:
      MathException - if arrays are null, different lengths, fewer than 2 categories, or contain invalid values

    • independence

      public static TestResult independence(double[][] contingencyTable)
      Performs a chi-squared test of independence on a contingency table. 对列联表执行卡方独立性检验

      Tests whether two categorical variables are independent. df = (rows - 1) * (cols - 1).

      检验两个分类变量是否独立。 df = (rows - 1) * (cols - 1)。

      Parameters:
      contingencyTable - the contingency table (at least 2x2, all values non-negative) / 列联表（至少 2x2，所有值非负）
      Returns:
      the test result / 检验结果
      Throws:
      MathException - if table is null, too small, jagged, or contains invalid values