Final answer:
Archival research is a method that involves using past records or data sets to answer research questions and look for patterns or relationships, but it cannot establish cause-and-effect.
Step-by-step explanation:
Researchers use archival research as a method to investigate research questions by examining existing records or data sets. This approach does not involve direct interaction with research participants but rather relies on analyzing previously collected data to uncover interesting patterns or relationships. By studying archival data, researchers can answer various research questions, such as identifying risk factors for students struggling academically or understanding who is most likely to complete their education, as illustrated in Figure 2.10 and the case of analyzing academic records of college students.
It's essential to note that while archival research can indicate important relationships between variables, it doesn't allow for making claims about cause-and-effect, which requires an experimental design. Also, since the researchers have no control over what and how the original data was collected, the research questions must align with the information available in the existing data sets.