Known for his rigorous cinematic experiments and precise control of visual information, Mr. Egoyan works in a more straightforward manner this time.

Lack of rigorous controlled experiments, which are far from mimicking oil reservoir conditions that may have an effect over gene expression and protein formation.

The random assignment of individuals to groups (or conditions within a group) distinguishes a rigorous, "true" experiment from an adequate, but less-than-rigorous, "quasi-experiment".

His goal was to turn the children into Renaissance men and women, and his son was a beneficiary of his intellectually rigorous experiment.

Physics might be defined as the study of patterns in nature: patterns described by mathematically-expressed models, which are then tested by rigorous experiment.

However, because rigorous experiments have not been carried out on cosmological length scales, general relativity could conceivably be inaccurate.

Instead, Jahn posed this question: Do I have an obligation to follow up the student's work with more rigorous experiments?

This was a single-blind experiment, not a more rigorous double-blind experiment.

"Not a very rigorous experiment," he said.

This was hardly a rigorous scientific experiment.