In introductory research methods, which strategy best helps psychologists reduce observer bias when recording participants’ behavior?

• A. Allow each observer to use their own personal judgment and adjust codes as the study progresses.
• B. Use observers who are blind to the study’s hypothesis and participants’ condition, and train them with standardized coding rules.
• C. Have the same observer collect the data and analyze the results to ensure consistency.
• D. Increase the sample size so that any observer bias is eliminated automatically.

Answer: (B)

Verified step by step guidance

1. Understand that observer bias occurs when the expectations or beliefs of the observer influence their recording of participants' behavior, potentially skewing the data.
2. Recognize that allowing observers to use personal judgment or adjusting codes during the study can increase bias rather than reduce it, as it introduces subjectivity.
3. Consider that having the same observer collect and analyze data might improve consistency but does not eliminate bias because the observer's expectations remain unchallenged.
4. Note that increasing sample size improves statistical power but does not directly address observer bias, which is a systematic error in data recording.
5. Identify that the best strategy to reduce observer bias is to use observers who are blind to the study’s hypothesis and participants’ conditions, combined with thorough training using standardized coding rules to ensure objective and consistent data collection.