Describe how psychological theories guide scientific research.

A useful theory effectively organizes a wide range of observations and implies testable predic- tions, called hypotheses. By enabling us to test and reject or revise a particular theory, such pre- dictions give direction to research. They specify in advance what results would support the theory and what results would disconfirm it. As an additional check on their own biases, psychologists report their results precisely with clear operational definitions of concepts. Such statements of the procedures used to define research variables allow others to replicate, or repeat, their observations. Often, research leads to a revised theory that better organizes and predicts observable behaviors or events.