• ARDL stands for Autoregressive Distributed Lag. This model allows for short- and long-run relationships between variables. The ARDL model is often used when the variables are integrated into order one (I(1)).
• ARDL error correction model regression is a type of ARDL model that includes an error correction term. The error correction term captures the speed at which the variables return to their long-run equilibrium after a shock.
• ARDL long run form bound test is a test of statistics that can be used to test for a long-run relationship between two or more variables. The test depends on the idea that the error correction term will be significant if the variables have a long-run relationship.

The main difference between ARDL, ARDL error correction model regression, and ARDL long run form bound test is the type of analysis used. ARDL is a general model that can @analyze both short-run and long-run relationships. ARDL error correction model regression is a more specific model used to analyze the speed at which variables return to their long-run equilibrium. ARDL long run form bound test is a test of statistics that can be used to test for a long-run relationship between two or more variables.

Which method is best depends on the specific research question you are trying to answer. If you are interested in both the short-run and long-run relationships between variables, then ARDL is a good choice. If you are interested in the speed at which variables return to their long-run equilibrium, then ARDL error correction model regression is a good choice. If you want to test for a long-run relationship between variables, then ARDL long-run form bound test is a good choice.

I found it difficult to answer this question without access to some symbols. I have attached a pdf which should be more readable than what I might present here

ARDL stands for Autoregressive Distributed Lag model. It is a statistical model used to analyze time series data. ARDL error correction model regression is an extension of the ARDL model that includes an error correction term. This term helps to correct for any deviations from long-run equilibrium in the short run. ARDL long run form bound test is a test used to determine whether there is a long-run relationship between two or more variables in an ARDL model.