Quality issues when using Big Data in Official Statistics

The use of Big Data (BD) for improving the statistics and reducing the costs is a great opportunity and challenge for the National Statistical Offices (NSOs). Often the debate on BD is focused on the IT issues to deal with their volume, velocity, variety. Nevertheless, the NSOs have to be assured that the estimates have a good level of accuracy as well. This paper evaluates when estimators using Internet web scraped variables from a list of enterprise websites, suffering from selectivity concerns, are competitive with respect to a survey sampling estimators. A Monte Carlo simulation using a synthetic population based on real data is implemented to compare predictive estimators based on BD, survey estimators and blended estimators combining predictive and survey estimators.