Joshua designs a research study to investigate the relationship between two variables: the size of a person’s head and I. Q. level. He measures each variable without manipulating either of the variables and finds that I. Q. is higher for subjects with bigger heads. In the context of correlational research, what can Joshua conclude?

IQ and head size are positively correlated.            

Explanation:

Correlational research: In scientific and psychological research, The term, "correlational research" is determined as one of the different types of "non-experimental research" methods in which an investigation, researcher, or experimenter tend to measure or evaluate two different variables and therefore assess and understands the "statistical relationship" between the given variables in the absence of any influence from the extraneous variable.

Positive correlation: Relationship between two different variables that move in a similar direction.

In the question above, Joshua can conclude IQ and head size are being positively correlated.

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