In which research situation below would an extraneous variable become a confounding variable?

A researcher is intrigued by an explanation of children’s problem-solving strategies found in a journal article and develops a research study to determine whether the article’s ideas are correct. This study can be classified as ____ research.

While watching your kids play in the backyard, you get some ideas about what factors may be causing them to compete or collaborate. This is an example of getting research ideas from ____.

A refutable hypothesis must ____.

A researcher would like to examine the political attitudes for students at a local university. The researcher will evaluate a sample of 200 students but would like to be sure that the ages and genders of individuals in the sample accurately represent the ages and genders for the entire student body at the university. What would be the best sampling method for the researcher to use?

Which relationship described below illustrates a negative relationship?

A researcher finds that room color influences the mood of 45-year-old women in a sample. To preserve external validity, the researcher should generalize these findings to which group?

A measurement procedure can be reliable without being valid.

Selection bias is a threat to external validity.

Which potential problem can occur when the rational method is used?