quality-indicators-2017

QUALITY INDICATORS 2017
4.1.2 Overcoverage rate
With regard to the definition in Section 3.7, the overcoverage rate is equal to the rate of ineligible units in the
frame. If we wish to apply such definition also to register-based surveys, we first need to assume that the entire
procedure is implemented in such a manner that the referential set of observation units (the frame) to which
data from heterogeneous sources are linked is defined at the beginning. In this case as well as for the definition
of indicators described in the following sections, we assume the situation presented in the following figure:
Figure 4.2: Process of integration of heterogeneous sources
Data sources
…
Frame
Integration
Complete and
partial data
No data –
eligible
No data –
ineligible
F
r
a
m
e
Units for which we were not able to obtain the required data can thus also here be divided into eligible and
ineligible units, and then the rate can be calculated according to the same procedures as described in Section
3.5. The problem, however, is how to identify such ineligible units because in field surveys such information is
usually obtained from the field, while in this case there is no such contact, or (in combined surveys) the contact
is rather limited. We therefore usually need to use information from other surveys or use additional
administrative sources.
4.1.3 Imputation rate
As presented in the above figure, in the phase of data integration not all units are linked for all variables (see
Section 3.8); in this case, too, we face a problem that corresponds to the problem of unit non-response and item
non-response in field surveys. Moreover, in particular in the integration of several heterogeneous sources, there
is a high probability that inconsistent records might be created. In register-based surveys, all of the above
creates the need for different imputation methods to be used for the estimate of unavailable data, or the
estimate for inconsistent data replacement. By using these methods, the value of the indicator is then calculated
according to the same procedure as described in 3.8.
4.1.4 Editing rate
Data validation and data editing are procedures to be implemented in field surveys as well as in register-based
and combined surveys. A specific characteristic of register-based surveys (regarding editing) is that editing
procedures may be carried out on an individual source (prior to integration) or on an already linked data set
(after integration). In calculating the indicator value, we need to consider corrections made prior to and after
integration. In short, we take into consideration any correction made during the survey in question. On the other
hand, we should not take into account those changes to data that have been made outside the scope of the
survey, those undertaken by the data administrator at the SURS, or those undertaken by an external institution.
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