Experimentation

Experimentation is a systematic process used to investigate cause-and-effect relationships by deliberately manipulating one or more independent variables and observing effects on dependent variables, while attempting to control or randomize other factors. The approach is central to the scientific method and to evidence-based practice.

A well-designed experiment includes a clear hypothesis, defined variables (independent, dependent, and controlled), a plan for randomization, a control group, and procedures for measurement and replication. Randomization minimizes bias; a control condition provides a baseline; blinding reduces expectancy effects.

Common designs include randomized controlled trials, factorial experiments, crossover studies, and matched-pairs designs. Between-subject designs compare different participants across conditions; within-subject designs reuse participants. Replication across experiments and populations strengthens reliability.

Ethical considerations are central, especially in research with humans or animals. Informed consent, risk assessment, and approval by oversight bodies govern human studies; animal welfare guidelines regulate animal experiments. Statistical analysis, preregistration, and reporting standards promote transparency.

The practice spans the natural and social sciences, engineering, medicine, psychology, and computer science, including computer-based simulations and in silico experiments. Limitations include imperfect control of confounding variables, measurement error, and the generalizability of findings.