Match each term related to psychological research with its correct definition.

A psychology researcher is conducting a study on social media habits and records whether each participant's primary platform is 'TikTok', 'Instagram', or 'YouTube'. Which of the following correctly identifies and explains the type of variable being measured in this scenario?

A researcher is studying the effects of sleep deprivation on coordination and records the number of errors participants make while completing a motor task. In this research study, 'number of errors' is correctly classified as a categorical variable.

A developmental psychologist is deciding how to measure 'household income' to study its relationship with child vocabulary size. To ensure the highest level of statistical sensitivity, the researcher must evaluate whether to use a quantitative or categorical variable. Arrange the following steps in the logical order of this evaluative process.

In psychological research, what is the term for any characteristic or factor that can differ or change across individuals, situations, or over time?

In psychological research, the term 'variable' refers exclusively to characteristics that can be measured with numerical values.

A researcher studying sleep habits records the exact number of hours participants sleep each night. If the researcher later decides to analyze this data by splitting the participants into $2$ groups—'Sufficient Sleep' ($7$ or more hours) and 'Insufficient Sleep' (fewer than $7$ hours)—the researcher has transformed a quantitative variable into a(n) _____ variable.