Stationary and non stationary in econometrics

1. What is stationarity and non stationarity in econometrics?
2. What is stationary in econometrics?
3. How can you tell if data is stationary or nonstationary?
4. What does nonstationary mean?

What is stationarity and non stationarity in econometrics?

A stationary time series has statistical properties or moments (e.g., mean and variance) that do not vary in time. Stationarity, then, is the status of a stationary time series. Conversely, nonstationarity is the status of a time series whose statistical properties are changing through time.

What is stationary in econometrics?

A stationary process has the property that the mean, variance and autocorrelation structure do not change over time.

How can you tell if data is stationary or nonstationary?

A quick and dirty check to see if your time series is non-stationary is to review summary statistics. You can split your time series into two (or more) partitions and compare the mean and variance of each group. If they differ and the difference is statistically significant, the time series is likely non-stationary.

What does nonstationary mean?

moving or changing rather than staying still: We are operating in a nonstationary but stable environment. The shape of the graph will change when inflation is non-stationary. More examples.