What refers to a bias that occurs due to the expectations of the researcher affecting the study's outcomes?

The correct response identifies experimenter bias as the phenomenon where researchers' expectations or beliefs inadvertently influence the outcomes of a study. This form of bias can manifest in various ways, such as through the way the researcher interacts with participants, interprets data, or even in the design of the study itself.

When researchers have certain expectations about the results, they may unintentionally convey those expectations to the participants, which can lead to altered responses or behaviors. This is particularly pertinent in experiments where the researcher is actively involved, as their subtle cues may encourage participants to respond in a way that favors the hypothesis. Managing this bias is crucial to maintaining the integrity and validity of the research findings.

Other types of biases, such as observer effect, response bias, and selection bias, relate to different aspects of research methodology. Observer effect focuses on how the mere presence of an observer can influence participants' behavior. Response bias deals with tendencies of participants to respond inaccurately or falsely due to various factors, such as social desirability. Selection bias occurs when the sample used in a study is not representative of the larger population, leading to skewed results. Each of these biases affects research outcomes but in distinct ways compared to experimenter bias.