In appraisal practice, which of the following is never permitted?

In appraisal practice, the presence of bias is strictly prohibited because it undermines the integrity and objectivity that are essential to providing an accurate and fair appraisal. Appraisers have an ethical obligation to remain impartial and to provide valuations based solely on factual data, market conditions, and recognized appraisal methodologies without being influenced by personal feelings or external pressures.

Bias can distort the appraisal process, leading to evaluations that do not truly reflect the property's value. Maintaining objectivity ensures that the appraiser's work adheres to the principles and guidelines established by the Uniform Standards of Professional Appraisal Practice (USPAP), which aim to promote trust in the appraisal process and protect the interests of clients and the public.

The other options—collusion, partiality, and negligence—reflect unethical behavior or misconduct, but bias specifically refers to a subjective influence on the appraisal outcome itself, making it a fundamental violation of appraisal standards that could lead to significant consequences for the appraiser.