Interpreting R Outputs

Question 1

In ADF output, what result supports stationarity?

Answer 1

A test statistic more negative than the critical value → reject
𝐻0
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Question 2

In regression output, how do you test for coefficient significance?

Answer 2

Divide the coefficient by its standard error and compare to critical t-value or use p-value

Question 3

In BP or BG test output, what does a low p-value mean?

Answer 3

Evidence against the null → presence of heteroskedasticity or serial correlation

Question 4

In forecast comparison tables, which metrics do we look for?

Answer 4

RMSE, MAE, MAPE — lower is better

Question 5

What causes forecast intervals to widen over time?

Answer 5

Uncertainty from shocks accumulates as the horizon increases