hypothesewaarde

The hypothesewaarde is the value of a population parameter that is specified in the null hypothesis of a statistical test. It is a fixed value, chosen before collecting data, and serves as the benchmark against which observed data are evaluated. For example, in a test of a mean, the hypothesewaarde is the mu0 under H0.

In hypothesis testing, the sampling distribution under the null is constructed assuming the parameter equals the hypothesewaarde, and a test statistic is used to decide whether to reject H0. The p-value is the probability, under H0, of obtaining a value as extreme or more extreme than the observed statistic. The choice of hypothesewaarde influences the p-value and the final decision.

Common examples include mu0 in a one-sample test, p0 in tests of a proportion, or sigma0 in tests of variance. The hypothesewaarde is often based on prior research, regulatory standards, or practical relevance.

The hypothesewaarde is not the observed data and is not proven or disproven by the data alone; it is a component of the null model. Confidence intervals and equivalence testing can relate to the hypothesewaarde: if mu0 lies inside a confidence interval, it is compatible with the observed data at the chosen confidence level, but this does not by itself prove H0.

In practice, transparency about the hypothesewaarde and its justification is essential for interpreting test results and for replication.