What Does It Mean for a Series to Have a Unit

question 7

Multiple Choice

What does it mean for a series to have a unit root?

• A)it has a constant mean equal to 1
• B)it has a constant variance equal to 1
• C)it is stationary
• D)it is integrated of order 1

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Definitions:

Random Sampling

A method in statistical analysis where individuals or items are selected from a larger population entirely by chance, ensuring that every member has an equal opportunity of being chosen.

Convenience Sampling

A non-probability sampling method where participants are selected based on their availability and proximity to the researcher.

Judgment Sampling

A sampling method where the samples are selected based on the opinion of an expert, rather than random selection.

Central Limit Theorem

A statistical theory stating that, given a sufficiently large sample size from a population with a finite level of variance, the mean of all samples from the same population will be approximately equal to the mean of the population.