Question

Tammy’s experiment compared the effectiveness of videotape and textbook presentation of a history lesson. Unexpectedly, her demeanor changed with each treatment condition. She appeared worried during the videotape condition because the audiovisual equipment periodically broke down. In contrast, she seemed relaxed in the textbook condition during which subjects read from a book. Which problem does this illustrate?a. confounding by a context variable

b. experimenter bias
c. history threat
d. selection threat

Answer 1

b. experimenter bias

Step-by-step explanation:

experimental bias, is a mechanism where researchers influence the outcome to produce certain results.

Experimental bias constitutes the experimenter's behaviour, which in an observational study creates confusion.