Experimenter's bias is the phenomenon in which the researcher's expectations, beliefs, or values can influence the results of an experiment. This bias can occur when the researcher's expectations affect the design of the experiment, the data collection process, or the interpretation of the results. It is important
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Observer bias is one of the types of detection bias and is defined as any kind of systematic divergence from accurate facts during observation and the recording of data and information in studies. The definition can be further expanded upon to include the systematic difference between what is observed due to variation in observers, and what the true value is.