In experimental science, experimenter's bias is subjective bias towards a result expected by the human experimenter. David Sackett, in a useful review of biases in clinical studies, states that biases can occur in any one of seven stages of research:
- in reading-up on the field,
- in specifying and selecting the study sample,
- in executing the experimental manoeuvre (or exposure),
- in measuring exposures and outcomes,
- in analyzing the data,
- in interpreting the analysis, and
- in publishing the results.
The inability of a human being to be objective is the ultimate source of this bias. It occurs more often in sociological and medical sciences, where double blind techniques are often employed to combat the bias. But experimenter's bias can also be found in some physical sciences, for instance, where the experimenter rounds off measurements.
Famous quotes containing the word bias:
“The solar system has no anxiety about its reputation, and the credit of truth and honesty is as safe; nor have I any fear that a skeptical bias can be given by leaning hard on the sides of fate, of practical power, or of trade, which the doctrine of Faith cannot down-weigh.”
—Ralph Waldo Emerson (18031882)