Hi all, Ok, this is not such a great topic but I'm going to submit it anyway... In an estimation output, gretl uses the expression "using observations...", for example: for time series, "Model 1: OLS, using observations 1952-1981 (T = 30)" (1) or, for undated dataset, "Model 1: OLS, using observations 1- 30” (2) And this does make sense when all observations are in a row. When missing/uncomplete observations exist, gretl also provides additional information: "Missing or incomplete observations dropped:" (3) Now, when data are sub-sampled on a conditional criteria), (1) and (2) are (always?) reframed, for example, "Model 1: OLS, using observations 1-13" (4) and here "using observations..." loses its meaning given that the actual observations used in the estimation are not in a row anymore. What if “using observations” in (4) be replaced simply by the number of observations used and additionnal info like (4) be provided informing the user that sub-sampled data are used. This will make a clear difference with (1) and (2)* the only cases when all observations used are in a row. *Note than (2) is correct even for time series sub-sampled data but yet with all observations in a row. Thank you for reading, Best, Artur