Vita e Pensiero

Secondo fascicolo del 2019

The Big Data expands the range of sources that have the potential to be used for Official Statistics and represents an effective reply to the declining response rates and the rising costs of conducting surveys, offering, in the meanwhile, potentially more timeliness and granular statistics...

The mixed-mode design are adopted by NSIs both to contrast declining response and coverage rates and to reduce the cost of the surveys. However, mixed-mode design introduces several issues, such as a possible increase in the total survey error due to extra measurement error introduced by additional data collection modes and a selection effect due to differences in the population coverage and in nonresponse processes...

Hybrid calibration refers to an approach where techniques of classical calibration and more recent model-assisted calibration are combined for a joint calibration methodology. The classical calibration does not assume a model but uses the original auxiliary data as aggregates, whereas in model calibration, unit-level predictions from a model are used as pseudo auxiliary information. By combining these approaches we introduce hybrid methods, where aggregate data from different levels of the population are supplied to the model-free component and unit-level data are incorporated into the model-assisted component...

Primo fascicolo del 2019

In this paper, a new sampling technique is proposed that carries more information than contained in ranked set sample (RSS). The proposed sampling technique is defined by making the use for the idea of visual grouping of population units with respect to a fixed threshold and RSS. We refer to it as RSS-Grouping technique. Under the best informative RSS-Grouping technique, the maximum likelihood estimator (MLE) of the mean of an exponential distribution is derived...