Features of science: objectivity and the empirical method; replicability…

The idea

Objectivity means keeping expectations out of data using standardised, blind designs. The empirical method insists claims rest on direct observation. Replicability requires methods detailed enough to repeat, establishing reliability. Popper's falsifiability means a theory earns scientific status by making predictions that could be proven false. Theory construction involves gathering empirical evidence to build a framework explaining phenomena. This enables hypothesis testing, generating specific, testable predictions to see if the theory holds or needs modification. Kuhn added the paradigm, the shared assumptions of a discipline; psychology's lack of a single one makes it a pre-science, and accumulated anomalies force a paradigm shift.

What earns the marks

• Defines objectivity as freedom from personal bias, linked to standardised and blind procedures.
• Defines the empirical method as gathering evidence through direct observation and measurement.
• Explains replicability as a method detailed enough to be repeated, and why repetition matters for reliability.
• Explains falsifiability, crediting Popper, with an example of a theory that cannot be falsified.
• Explains theory construction as building explanations from empirical evidence, and hypothesis testing as generating testable predictions from theories.
• Explains paradigms and paradigm shifts, crediting Kuhn, and applies the pre-science argument to psychology.

Common mistakes and how to put them right

• Defining falsifiability as a theory being false, rather than being capable of being proved false.

• Describing a paradigm as a theory.

  Put it right: It is the set of shared assumptions that a whole discipline works within.

• Confusing theory construction (building the theory) with hypothesis testing (testing predictions derived from it).

• Treating replicability and reliability as the same thing, rather than one being how the other is tested.

Exam tips

• Questions on this topic often require you to apply the features of science to a specific psychological approach or study, so be prepared to link concepts like falsifiability to concrete examples.
• Credit Popper and Kuhn by name; attribution is frequently a discrete mark.
• Use the cognitive revolution, or behaviourism's fall, as the worked example of a paradigm shift.