skjevheter

Skjevheter is a Norwegian term that can refer to two related concepts: statistical skewness in a distribution and cognitive or methodological biases in judgment and research.

Statistical skewness describes asymmetry in the distribution around its mean. If the bulk of observations lie on the left and the tail on the right, the skew is positive; if the opposite, negative. Skewness is measured by the standardized third moment or by sample methods such as the Pearson measures.

Cognitive biases are systematic errors in thinking that affect judgments and decisions. Examples include confirmation bias, where evidence supporting preconceptions is favored; availability heuristic; anchoring effect; representativeness bias; and more general biases in data interpretation such as sampling bias and publication bias.

Bias can arise in data collection and analysis: sampling bias, selection bias, measurement bias, recall bias, nonresponse bias, confounding. Mitigation includes random sampling, blinding, preregistration, proper study design, data weighting, robust statistical methods, and transparency.

In statistics and research, recognizing skewness and biases helps choose appropriate methods (nonparametric tests, data transformation, bootstrapping) and improve validity. In everyday discourse, awareness of skjevheter supports careful interpretation of information.