Data at a specific moment in time is described as...

• A. Time series data
• B. Panel data
• C. Longitudinal data
• D. Cross-sectional data

Answer: (D)

Cross-sectional data capture observations from many units at a single moment, allowing comparisons across those units at that specific time. This is like surveying households on one particular date to measure income, age, and education for each household, rather than tracking how those variables change over time. Time series data follows the same variable over multiple time periods for one unit (or a consistent unit across time), panel data combines multiple units over multiple time points, and longitudinal data is another way of referring to repeated observations of the same units over time. Because the data are collected at one moment across many units, it describes cross-sectional data.