Controls

• Random allocation is used to ensure all participants have an equal chance of being allocated into either condition, reducing selection bias.
• Random allocation can also reduce demand characteristics as there are no obvious differences between groups which may influence behaviour.
• A limitation of random allocation is that it does not guarantee balance across both groups, so some variables could still differ between them.
• By counterbalancing participants it ensures participants go in the different order so that order effects don’t skew the final result as the order effects from each group cancel each other out
• Standardisation is the term used to describe the 

  identical procedure set up in an experiment (or the questions used in self-report measures) across all conditions and participants
• Counterbalancing increases reliability by ensuring consistency in results when comparing two conditions
• Randomisation refers to the deliberate avoidance of bias on the part of the researcher to keep the research as objective as possible- used when constructing an experiment. Randomness simply describes a lack of purpose, cause, order or predictability where outcomes do not follow a predetermined pattern
• The aim of standardising procedures is to ensure that any observed difference between conditions is due to the independent variable rather than extraneous factors such as participant skill level, time of day etc.