SILC_ESQRS_A_IT_2011_0000 - Version 1

National Reference Metadata in ESS Standard for Quality Reports Structure (ESQRS)

Compiling agency: Italian National Institute of Statistics -Socio-economic Statistics Directorate

Time Dimension: 2011-A0

Data Provider: IT1

Data Flow: SILC_ESQRS_A


For any question on data and metadata, please contact: EUROPEAN STATISTICAL DATA SUPPORT


1. ContactTop
1.1. Contact organisationItalian National Institute of Statistics -Socio-economic Statistics Directorate
1.2. Contact organisation unitHouseholds economic conditions unit
1.5. Contact mail addressViale oceano Pacifico 171, 00100, Rome - ITALY


2. IntroductionTop
 

The production of quality reports is part of the implementation of the EU-SILC instrument. In order to assess the quality of data at national level and to make a comparison among countries, the National Statistics Institutes are asked to report detailed information mainly on: the entire statistical process, sampling and non-sampling errors, and potential deviations from standard definition and concepts.

 

This document follows the ESS standard for quality reports structure (ESQRS), which is the main report structure for reference metadata related to data quality in the European Statistical System. It is a metadata template, based on 13 main concepts, which can be used across several statistical domains with the purpose of a better harmonisation of the quality reporting requirements in the ESS.

 

For that reason the template of this document differs from that one stated in the Commission Reg. 28/2004.

 

Finally it is the combination of the previous intermediate and final quality reports therefore it is worth mentioning that it refers to both the cross sectional and the longitudinal data.

 

The EU-SILC (Statistics on Income and Living Conditions, Regulation of the European Parliament, no. 1177/2003) is one of the main sources of data for periodic reports on the social situation of the European Union and the spread of poverty in member countries. The core information of EU-SILC is essentially centered around the issues of income and social exclusion. The project is inspired by a multi-dimensional approach to the problem of poverty, with a particular focus on aspects of material deprivation.

Italy participates in the project with a survey on income and living conditions of households, conducted every year since 2004, providing statistics at both cross and longitudinal (households remain in the sample for four consecutive years). Although the EU-SILC Regulation require only the production of indicators at national level, in Italy the survey was designed to provide reliable estimates at regional level. Since 2007 the survey, in addition to net income, also provides an estimate of the gross income, allowing you to calculate the main economic and social indicators (poverty relative persistence of poverty in the state, dispersion around the line of poverty, income inequality ) before and after taxation and social transfers.
Since 2011 has been modified interview technique and the investigation is carried out through a CAPI (Computer Assisted Personal Interview).

 

 


3. Quality management - assessmentTop

Not requested by Reg. 28/2004


4. RelevanceTop
4.1. Relevance - User Needs

Not requested by Reg. 28/2004

4.2. Relevance - User Satisfaction

Not requested by Reg. 28/2004

4.3. Completeness

Not requested by Reg. 28/2004

4.3.1. Data completeness - rate

Not requested by Reg. 28/2004


5. Accuracy and reliabilityTop
5.1. Accuracy - overall
 

In terms of precision requirements, the EU-SILC framework regulation as well the Commission Regulation on sampling and tracing rules refers respectively, to the effective sample size to be achieved and to representativeness of the sample. The effective sample size combines sample size and sampling design effect which depends on sampling design, population structure and non-response rate.

5.2. Sampling error
 

EU-SILC is a complex survey involving different sampling design in different countries. In order to harmonize and make sampling errors comparable among countries, Eurostat (with the substantial methodological support of Net-SILC2) has chosen to apply the "linearization" technique coupled with the “ultimate cluster” approach for variance estimation. Linearization is a technique based on the use of linear approximation to reduce non-linear statistics to a linear form, justified by asymptotic properties of the estimator. This technique can encompass a wide variety of indicators, including EU-SILC indicators. The "ultimate cluster" approach is a simplification consisting in calculating the variance taking into account only variation among Primary Sampling Unit (PSU) totals. This method requires first stage sampling fractions to be small which is nearly always the case. This method allows a great flexibility and simplifies the calculations of variances. It can also be generalized to calculate variance of the differences of one year to another .

The main hypothesis on which the calculations are based is that the "at risk of poverty" threshold is fixed. According to the characteristics and availability of data for different countries we have used different variables to specify strata and cluster information. In particular, countries have been split into four groups:

1)BE, BG, CZ, IE, EL, ES, FR, IT, LV, HU, NL, PL, PT, RO, SI, UK and HR whose sampling design could be assimilated to a two stage stratified type we used DB050 (primary strata) for strata specification and DB060 (Primary Sampling Unit) for cluster specification;

2) DE, EE, CY, LT, LU, AT, SK, FI, CH whose sampling design could be assimilated to a one stage stratified type we used DB050 for strata specification and DB030 (household ID) for cluster specification;

3) DK, MT, SE, IS, NO, whose sampling design could be assimilated to a simple random sampling, we used DB030 for cluster specification and no strata;

 

The Eurostat methodology is accepted by Italy.

5.2.1. Sampling error - indicators
 
  AROPE At risk of poverty
(60%)
Severe
Material Deprivation
Very low
work intensity

Ind.

value

Stand. errors

Half

CI (95%)

Ind.

value

Stand. errors

Half

CI (95%)

Ind.

value

Stand. errors

Half

CI (95%)

Ind.

value

Stand. errors

Half

CI (95%)

Total

 28.2  0.48  0.94  19.6  0.42  0.82  11.2  0.43  0.84  10.4  0.28  0.55

Male

 26.4  0.54  1.06  18.3  0.45  0.88  10.9  0.46  0.9  9.2  0.31  0.61

Female

 29.9  0.50  0.98  20.8  0.45 0.88   11.5  0.43  0.84  11.6  0.34  0.67

Age0-17

 32.3  0.88  1.73  26.3  0.86  1.69  12.3  0.76 1.49  7.6  0.4  0.79

Age18-64

 28.4  0.52  1.02  18.5  0.43  0.84  11.0  0.43  0.84  11.2  0.3  0.59

Age 65+

 24.2  0.66  1.3  17.0  0.52  1.02  10.9  0.53  1.04  -   -   -

Alternative Sampling Error Table View

Indicator

Breakdown

Indicator value

SE %

CI95% lower bound

CI95% upper bound

 

Total

28.2

0.48

27.3

29.2

 

Male

26.4

0.54

25.4

27.5

 

Female

29.9

0.50

28.9

30.9

AROPE

Age 0-17

32.3

0.88

30.5

34.0

 

Age 18-64

28.4

0.52

27.4

29.4

 

Age 65+

24.2

0.66

22.9

25.5

 

 

 

 

 

 

 

Total

19.6

0.42

18.8

20.4

 

Male

18.3

0.45

17.4

19.1

 

Female

20.8

0.45

19.9

21.7

ARPT60

Age 0-17

26.3

0.86

24.7

28.0

 

Age 18-64

18.5

0.43

17.6

19.4

 

Age 65+

17.0

0.52

16.0

18.0

 

 

 

 

 

 

 

Total

11.2

0.43

10.3

12.0

 

Male

10.9

0.46

10.0

11.8

 

Female

11.5

0.43

10.6

12.3

SMD

Age 0-17

12.3

0.76

10.8

13.8

 

Age 18-64

11.0

0.43

10.1

11.8

 

Age 65+

10.9

0.53

9.9

12.0

 

 

 

 

 

 

 

Total

10.4

0.28

9.8

10.9

 

Male

9.2

0.31

8.6

9.8

LWI

Female

11.6

0.34

10.9

12.3

 

Age 0-17

7.6

0.4

6.77

8.5

 

Age 18-59

11.2

0.3

10.66

11.8

 

As comment:

Based of an hypothesis of agreement with the technical phase of construction of the sampling design: the Standard error of the (ARPR) at-risk of poverty rate 60% of median at family level , linearized with Taylor Woodruff Method, using (solely for this year) the Software Regenesees with Ultimate Cluster is 0.37 and the Deff at family level is 1.48

 

5.3. Non-sampling error
 

Non-sampling errors are basically of 4 types:

  • Coverage errors: errors due to divergences existing between the target population and the sampling frame.
  • Measurement errors: errors that occur at the time of data collection. There are a number of sources for these errors such as the survey instrument, the information system, the interviewer and the mode of collection
  • Processing errors: errors in post-data-collection processes such as data entry, keying, editing and weighting
  • Non-response errors: errors due to an unsuccessful attempt to obtain the desired information from an eligible unit. Two main types of non-response errors are considered:
  1. – Unit non-response: refers to absence of information of the whole units (households and/or persons) selected into the sample
  1. – Item non-response: refers to the situation where a sample unit has been successfully enumerated, but not all required information has been obtained
5.3.1. Coverage error
 

Coverage errors include over-coverage, under-coverage and misclassification:

  • Over-coverage: relates either to wrongly classified units that are in fact out of scope, or to units that do not exist in practice
  • Under-coverage: refers to units not included in the sampling frame
  • Misclassification: refers to incorrect classification of units that belong to the target population
5.3.1.1. Over-coverage - rate
 
 

Main problems

Size of error

Cross sectional

data

·Over-coverage

·Under-coverage

·Misclassification

NOT PRESENT

NOT PRESENT

NOT PRESENT

The definition of the sample population is not different from the definition of the target population, considering the registry office.

5.3.2. Measurement error
 

Cross sectional data

Source of measurement errors

Building process of questionnaire

Interview training

Quality control

 

 The final version of the questionnaire, as used in the survey 2007, revisited for the CAPI edition of the survey 2011, is based on (i) the first three waves of SILC surveys; (ii) the support of experts working in other research institutes; and (iii) a cognitive laboratory on self-employment. Information is collected through three main questionnaires: the first one collects information about each household member’s demographic characteristics, and child care; the second one collects information at household level; the third one collects information at individual level (about individual aged 16 and over).

This building process of questionnaire is likely to be affected by:  (i) memory effect, because information is collected according to respondents memories (official documentation about income is not required; external sources of information, as administrative registers, are used when available); (ii) omission, because respondents might not be willing to provide correct information about income or other living conditions; (iii) proxy effect, because in a few cases some individuals are allowed to provide information about other household members;

 

interviewers, who might provide the respondents with an incorrect interpretation of the questions, or might mistake when filling the questionnaire. A market research company in cooperation with Istat territorial offices, provides a CAPI interview survey. Interviewers are firstly trained and provided with training tools (e.g. instruction manuals, or presentations) by Istat. The market research company implements the questionnaire software (Converso) and provides support during the field work and control for the quality of the interviewers’ work. Training strategies have been outlined also on the experience of pilot surveys; registration and transmission process from Capi questionnaire,  although  automatic controls are implemented in the Capi software.

 

5.3.3. Non response error
 

Non-response errors are errors due to an unsuccessful attempt to obtain the desired information from an eligible unit. Two main types of non-response errors are considered:

1) Unit non-response which refers to the absence of information of the whole units (households and/or persons) selected into the sample. According the Commission Regulation 28/2004:

  • Household non-response rates (NRh) is computed as follows:

NRh=(1-(Ra * Rh)) * 100

Where Ra is the address contact rate defined as:

Ra= Number of address successfully contacted/Number of valid addresses selected

and Rh is the proportion of complete household interviews accepted for the database

Rh=Number of household interviews completed and accepted for database/Number of eligible households at contacted addresses

  • Individual non-response rates (NRp) will be computed as follows:

NRp=(1-(Rp)) * 100

Where Rp is the proportion of complete personal interviews within the households accepted for the database

Rp= Number of personal interview completed/Number of eligible individuals in the households whose interviews were completed and accepted for the database

  • Overall individual non-response rates (*NRp) will be computed as follows:

*NRp=(1-(Ra * Rh * Rp)) * 100

For those Members States where a sample of persons rather than a sample of households (addresses) was selected, the individual non-response rates will be calculated for ‘the selected respondent’, for all individuals aged 16 years or older and for the non-selected respondent.

2) Item non-response which refers to the situation where a sample unit has been successfully enumerated, but not all the required information has been obtained.

5.3.3.1. Unit non-response - rate
 

Cross sectional data

Address contact rate
(Ra)*

Complete household interviews
(Rh)*

Complete personal interviews
(Rp)*

Household Non-response rate
(NRh)*
Individual non-response rate
(NRp)*
Overall individual non-response rate
(NRp)*

A*

B*

A*

B*

A*

B*

A*

B*

A*

B*

A*

B*

 99.3  100  75.56  79.33  100  100  24.98  20.67  0 0  24.98 20.67

* All the formulas are defined in the Commission Regulation 28/2004, Annex II

A* = Total sample; B = * New sub-sample

For the Italian 2011 SILC survey the address contact rate (Ra), the proportion of completed household interviews accepted for the database (Rh), the household non-response rate (NRh), the proportion of complete personal interviews within the households accepted for the database (Rp), the individual non-response rates (NRp) and the overall individual non-response rates (NRp_overall) are shown below:

Household non-response rates (NRh) will be computed as follows:  NRh=(1-(Ra * Rh)) * 100

 

Where Ra is the address contact rate

   

Ra=Number of addresses successfully contacted/Number of valid addresses selected=

=∑ [DB120=11]/∑ [DB120=all]-∑ [DB120=23]

 

Rh is the proportion of complete household interviews accepted for the database 

 

Rh= Number of household interviews completed and accepted for data base/Number of eligible households at contacted addresses=

=∑[DB135=1]/∑[DB130=all]

 

For those Members States where substitutions are made in case of unit non-response, non-response rates will be calculated before and after substitutions.

  • Individual non-response rates (NRp) will be computed as follows: NRp=(1-(Rp)) * 100

Where Rp is the proportion of complete personal interviews within the households accepted for the database

  

Rp=Number of personal interviews completed/Number of eligible individuals in the households whose interviews were completed and accepted for the database=

=∑[RB250=11+12+13]/∑[RB245=1+2+3]

  • Overall individual non-response rates (*NRp) will be computed as follows: *NRp=(1-(Ra * Rh * Rp)) * 100

For those Members States where substitutions are made in cases of unit non-response, non-response rates will be calculated before and after substitutions.

For those Members States where a sample of persons rather than a sample of households (addresses) was selected, the individual non-response rates will be calculated for ‘the selected respondent’ (RB245=2), for all individuals aged 16 years or older (RB245=2+3) and for the non-selected respondent (RB245=3).

5.3.3.2. Item non-response - rate
 

The computation of item non-response is essential to fulfil the precision requirements concerning publication as stated in the Commission Regulation No 1982/2003. Item non-response rate is provided for the main income variables both at household and personal level.

5.3.3.2.1. Item non-response rate by indicator
 
 

Total hh gross income
(HY010)

Total disposable hh income
(HY020)

Total disposable hh income before social transfers other than old-age and survivors benefits
(HY022)

Total disposable hh income before all social transfers
(HY023)

% of household having received an amount  99.23  99.33  98.83  92.07
% of household with missing values (before imputation)  0.71  1.46  1.72  3.60
% of household with partial information (before imputation) 88.10   55.70  50.00  47.99

 

 

Imputed rent
(HY030)

Income from rental of property or land
(HY040)
Family/ Children related allowances
(HY050)
Social exclusion payments not elsewhere classified
(HY060)
Housing allowances
(HY070)
Regular inter-hh cash transfers received
(HY080)
Interest, dividends, profit from capital investments in incorporated businesses
(HY090)

% of household having received an amount

 100.00  13.48  25.14  2.42  3.55  3.63  39.12

% of household with missing values (before imputation)

 0.00  10.29  6.00  1.32  0.78  0.44  12.30

% of household with partial information (before imputation)

 0.00  1.06  0.77  0.04  0.13  0.05  1.67

 

  Cash or near-cash employee income
(PY010)
Other non-cash employee income
(PY020)
Income from private use of company car
(PY021)
Employers social insurance contributions
(PY030)
Cash profits or losses from self-employment
(PY050)
Value of goods produced for own consumption
(PY070)
Unemployment benefits
(PY090)
Old-age benefits
(PY100)
Survivors benefits
(PY110)
Sickness benefits
(PY120)
Disability benefits
(PY130)
Education-related allowances
(PY140

% of household having received an amount

 40.80  13.24  0.68  38.54  17.20 18.34  10.11  29.92  1.87  -  3.17  0.50

% of household with missing values (before imputation)

 1.15  8.54  100.00  100.00  10.15  0.13  0.43  0.08  0.02  -  0.05  0.06

% of household with partial information (before imputation)

 1.93  0.62  100.00  0.00  0.46  0.00  0.09  0.09  0.00  -  0.00  0.00

Income components at household level:

 Alternative Table View as requested by the previous NRME Template

 

Cross sectional

 
 

 

A*

B*

 

Total household gross income

0.71

88.10

 

Total disposable household income

1.46

55.70

 

Total disposable household income before social transfers other than old-age and survivors’ benefits

1.72

50.00

 

Total disposable household income including old-age and survivors’ benefits

3.60

47.99

 

Net income components at household level

 

 

 

Imputed rent

0.00

0.00

 

Income from rental of a property or land

10.29

1.06

 

Family/children related allowances

6.00

0.77

 

Social exclusion not elsewhere classified

1.32

0.04

 

Housing allowances

0.78

0.13

 

Regular inter-household cash transfer received

0.44

0.05

 

Interest, dividends, profit from capital investments in unincorporated business

12.30

1.67

 

Interest repayments on mortgage

13.36

0.00

 

Income received by people aged under 16

0.02

0.00

 

Regular taxes on wealth

24.28

2.87

 

Regular inter-household cash transfer paid

0.63

0.04

 

Repayments/receipts for tax adjustment

0.19

0.29

 

Value of goods produced by own-consumption

0.13

0.00

 

Gross income component at household level

 

 

 

Imputed rent

100.00

0.00

 

Income from rental of a property or land

10.29

3.05

 

Family/children related allowances

6.00

0.83

 

Social exclusion not elsewhere classified

1.32

0.08

 

Housing allowances

0.78

0.24

 

Regular inter-household cash transfer received

0.44

0.15

 

Interest, dividends, profit from capital investments in unincorporated business

12.30

26.42

 

Interest repayments on mortgage

15.00

0.00

 

Income received by people aged under 16

0.02

0.00

 

Regular taxes on wealth

24.28

2.87

 

Regular inter-household cash transfer paid

0.63

0.04

 

Tax on income and social contributions

6.59

78.68

 

Value of goods produced by own-consumption

0.13

0.00

 

A* = % of household with missing values before imputation; B* = % of household with partial information before imputation

 

 

 

Income components at personal level:

 

 

Cross sectional

 
 

 

A*

B*

 

Net income components at personal level

 

 

 

Employee cash or near-cash income

1.15

1.93

 

Non cash employee income

8.54

0.62

 

Company car

100.00

100.00

 

Contributions to individual private pension plans

0.61

0.00

 

Cash benefits or losses from self-employment

10.15

0.46

 

Pension from individual private plans

0.00

0.00

 

Unemployment benefits

0.43

0.09

 

Old-age benefits

0.08

0.09

 

Survivor' benefits

0.02

0.00

 

Disability benefits

0.05

0.00

 

Education related allowances

0.06

0.00

 

Gross income components at personal level

 

 

 

Employee cash or near-cash income

0.45

5.36

 

Non cash employee income

8.54

4.59

 

Company car

99.97

0.00

 

Employer's social insurance contribution

100.00

0.00

 

Contributions to individual private pension plan

0.61

0.00

 

Cash benefit or losses from self-employment

1.41

9.37

 

Pension from individual private plans

100.00

0.00

 

Unemployment benefits

0.22

9.73

 

Old-age benefits

0.05

0.63

 

Survivor' benefits

99.96

0.00

 

Disability benefits

0.05

0.00

 

Education related allowances

0.06

0.00

 

Gross monthly earnings of employees

5.32

0.00

 

A* = % of household with missing values before imputation; B* = % of household with partial information before imputation

 

 

Administrative data cover 95.3% of recipients of old age benefits, disability benefits and survivor’ benefits.

The total item non-response for total disposable household income is 1.46 per cent (number of observations is 283) and the total number of observations is 19.399 (unit=households). For unadjusted gender pay gap the total item non-response is 5.32 per cent (number of observations is 2155) and the total number of observations is 40.496 (unit=individuals 16 + ).

5.3.4. Processing error
 
Data entry and coding Editing controls
 The family will be visited by an interviewer (who performs the interview), provided with an identification tag, which performs on behalf of Istat data collection with the aid of a personal computer. The information is collected through a questionnaire on the laptop where the interviewer recorded the answers will be provided by the family. This interview method is known as CAPI (Computer Assisted Personal Interviewing).Data entry procedure is realised through the software Converso. The procedure contains automatic controls about: range of variable, main routes of questionnaire and any logical controls referred to internal inconsistence of collected information. Every control is set-up like “soft” in order to reduce typing errors.

Furthermore, the procedure provides for “hard” control in order to compare register and questionnaire information about household’s composition, and previous versions/editions of the survey.

 

Coding controls

Coding controls are implemented in post-data-collection-process based on donor method.

 

Main errors detected in the post data collection process

Main errors detected are:

 - Missing value.

 - Value outside acceptance range.

 - Incoherence value compared to other information in the same record.


 

5.3.4.1. Imputation - rate

Not requested by Reg. 28/2004

5.3.4.2. Common units - proportion

Not requested by Reg. 28/2004

5.3.5. Model assumption error

Not requested by Reg. 28/2004

5.3.6. Data revision

Not requested by Reg. 28/2004

5.3.6.1. Data revision - policy

Not requested by Reg. 28/2004

5.3.6.2. Data revision - practice

Not requested by Reg. 28/2004

5.3.6.3. Data revision - average size

Not requested by Reg. 28/2004

5.3.7. Seasonal adjustment

Not requested by Reg. 28/2004


6. Timeliness and punctualityTop
6.1. Timeliness

The length of time between data availability and the event or phenomenon that they describe is as requested by  Eurostat  Reg. 28/2004

6.1.1. Time lag - first result

The number of months from the last day of the reference period to the day of publication of first results is as requested by  Eurostat  Reg. 28/2004

6.1.2. Time lag - final result

The number of months from the last day of the reference period to the day of publication of complete and final results are as requested by Eurostat  Reg. 28/2004

6.2. Punctuality

Time lag between the actual delivery of the data and the target date when it should have been delivered as requested by  Eurostat  Reg. 28/2004

6.2.1. Punctuality - delivery and publication

The number of days between the delivery / release date of data and the target date on which they were scheduled for delivery/ release as requested by  Eurostat  Reg. 28/2004


7. Accessibility and clarityTop
7.1. Dissemination format - News release

Not requested by Reg. 28/2004

7.2. Dissemination format - Publications

Publication on Income and Living condition are downloadable at

http://www.istat.it/it/archivio/condizioni-economiche-delle-fami

alias

http://www.istat.it/en/archive/households-economic-conditions

 

or you can contact the Press release Center

7.3. Dissemination format - online database

 

Your direct access to the Italian National Institute of Statistics is:  I.STAT

I.Stat is the warehouse of statistics produced by Istat, a complete and homogeneous wealth of information unique for the Italian official statistics.

http://dati.istat.it/?lang=en

7.3.1. Data tables - consultations

Your direct access to the Italian Statistics is I.ISTAT

I.Stat is the warehouse of statistics produced by Istat, a complete and homogeneous wealth of information unique for the Italian official statistics.

http://dati.istat.it/?lang=en

7.4. Dissemination format - microdata access

At the following web address, Istat provides Micro-data access

http://www.istat.it/en/information/researchers/microdata-files

7.5. Documentation on methodology

The list of methodological documents is available on line throught a search engine.

http://www3.istat.it/dati/catalogo/ricerca.php?tipo=n&ciclo=0&stringa=reddito&settori[]=7&num_collana=

7.5.1. Metadata completeness - rate

Not requested by Reg. 28/2004

7.5.2. Metadata - consultations

Not requested by Reg. 28/2004

7.6. Quality management - documentation

Documentation on procedures applied for quality management and quality assessment are as requested by  Eurostat  Reg. 28/2004

7.7. Dissemination format - other

Not requested by Reg. 28/2004


8. ComparabilityTop
8.1. Comparability - geographical

Not requested by Reg. 28/2004

8.1.1. Asymmetry for mirror flow statistics - coefficient

Not requested by Reg. 28/2004

8.1.2. Reference population
 

Reference population

Private household definition Household membership
 Same definition as standard EU-SILC  
  • the private household definition: in accordance with the Commission Regulation (EC) N° 1980/2003 (Annex I. paragraph 1.1), that allow to the Member States for using the common household definition defined in their own national statistical system. IT-SILC uses the following household definition: “cohabitants related through marriage, kinship, affinity, adoption, patronage and affection”;
 
  • the household membership:  IT-SILC does not include live-in domestic personnel au pairs. Concerning these persons, only some socio-demographic information are collected (date of birth, sex, marital status, duration of stay in the household). The number of these persons included in the sample was 162 (0.82% with respect to the total number of households and 0.4% with respect to interviewed individuals). 

 

 

 

8.1.3. Reference Period
 
Period for taxes on income and social insurance contributions Income reference periods used Reference period for taxes on wealth Lag between the income ref period and current variables
same definition as standard EU-SILC same definition as standard EU-SILC  same definition as standard EU-SILC  in the Italian EU-SILC survey of 2011,  current variables are referred to the moment of interview that is about 9 months after the end of the income reference period

 

 

 

 

 

the total duration of the data collection of the sample: 4 months. starting from the transmission of questionnaires to interviewers until their return back.

 

— basic information on activity status during the income reference period: same to the standard EU-SILC concept;

 

Components of income

 

Differences between the national definitions and standard EU-SILC definitions

 

— total household gross income: same definition as standard EU-SILC;

 

— total disposable household income: same definition as standard EU-SILC;

 

— total disposable household income. before social transfers other than old-age and survivors' benefits: same definition as standard EU-SILC;

 

— total disposable household income. before social transfers including old-age and survivors' benefits: same definition as standard EU-SILC;

 

— imputed rent: estimated by a semilogarithmic regression (log of the rent, avoiding the re-trasformation bias) with self-selection correction à la heckman. In the first stage, we run distinct probit models for owners/renters at a below-the-mkt price/free tenants vs tenants at a mkt price. Seniority is included between regressors, but its effect is depurated (parameter from regression equal to 0) in estimating predicted values for sub-populations other than tenants at a mkt rate;

 

— income from rental of property or land: same definition as standard EU-SILC;

 

— family/children-related allowances: same definition as standard EU-SILC;

 

- social exclusion payments not elsewhere classified: same definition as standard EU-SILC;

 

— housing allowances: same definition as standard EU-SILC;

 

— regular inter-household cash transfers received: same definition as standard EU-SILC;

 

— interest. dividends. profit from capital investments in unincorporated businesses: same definition as standard EU-SILC;

 

— interest paid on mortgages: same definition as standard EU-SILC;

 

— income received by people aged under 16: same definition as standard EU-SILC;

 

— regular taxes on wealth: same definition as standard EU-SILC;

 

— regular inter-household transfers paid: same definition as standard EU-SILC;

 

— tax on income and social insurance contributions: same definition as standard EU-SILC;

 

— repayments/receipts for tax adjustments: repayments/receipts for tax adjustments are those paid in the n+1 year, where n is the income reference period. This is consistent with the (optional) definition of taxes as 'taxes due on the incomes of the reference period'.

 

— cash or near-cash employee income: same definition as standard EU-SILC;

 

— non-cash employee income: the value of the company car for personal use is the user's cost estimated by the ACI (Automobile Club Italiano);

 

— employers' social insurance contributions: includes also contribution for Cococo “co-ordinated and continuative collaborators”, a special category of status in employment;

 

— cash profits or losses from self-employment (including royalties): the standard procedure requires to collect the amount of money drawn out of self-employment activity only when the profit/loss resulting from accounting books or the taxable self-employment income (net of corresponding taxes) are not available. For the Italian EU-SILC, both administrative and survey micro-data are available, through an exact matching of tax and sample records. The income from self-employment is set equal to the maximum value between: (i) the (net) self-employment income resulting from the Tax Report and (ii) the (net) self-employment income reported by the interviewee. In the questionnaire, the self-employment income question is preceded by a 'reminder question' that provides a YES/NO list of the possible personal uses of earnings (consumption and saving). The departure from the standard definition (using both sampling and administrative data) is adopted in order to minimise either tax avoidance in the administrative data or under-reporting in the survey data, depending on which of the two is greater. With respect to the standard one, the procedure adopted for the Italian EU-SILC leads to more comparable data, under the assumption that other countries' self-employment incomes are not underestimated;

 

— value of goods produced for own consumption: same definition as standard EU-SILC;

 

— unemployment benefits: same definition as standard EU-SILC;

 

— old-age benefits: same definition as standard EU-SILC;

 

survivors' benefits: same definition as standard EU-SILC;

 

sickness benefits. paid sickness leaves of employees are included in the dependent employment incomes;

 

— disability benefits: same definition as standard EU-SILC;

 

— education-related allowances: same definition as standard EU-SILC;

 

— gross monthly earnings for employees: same definition as standard EU-SILC;

 

The source or procedure used for the collection of income variables

 

The sources or procedures used for the collection of income variablesare Paper and pencil interviews (CAPI) for all income variable, including the money drawn out of business by the self-employed and administrative data. Administrative data have been linked to sample data and used for estimating data on employee income, pensions and self-employment incomes.

 

The form in which income variables at component level have been obtained

 

All income variables at component level are both net and gross of taxes and social security contribution at source.

 

The method used for obtaining income target variables in the required form

 

Gross values are estimated by a new methodology using in conjunction an exact record linkage between survey and fiscal data at micro level and a microsimulation model (Siena Microsimulation Model SM2-EU-SILC). The integration of microsimulation with register data has the advantage of using administrative data for the validation of microsimulation results. On the other hand, SM2-EU-SILC estimates those tax and social insurance contributions not covered by register data.  Four main register data are used: 730 tax returns used by employees and pensioners, UNICO tax returns used primarily by self employed workers, CUD  employers’ tax statements which include also data on social security contributions, and Pension Register Data. Both the use of administrative data and microsimulation estimates  improves the quality and the amount of information on gross income variables.

8.1.4. Statistical concepts and definitions
 
Total hh gross income
(HY010)
Total disposable hh income
(HY020)
Total disposable hh income before social transfers other than old-age and survivors' benefits
(HY022)
Total disposable hh income before all social transfers
(HY023)
F F F F

 

Imputed rent
(HY030)
Income from rental of property or land
(HY040)
Family/ Children related allowances
(HY050)
Social exclusion payments not elsewhere classified
(HY060)
Housing allowances
(HY070)
Regular inter-hh cash transfers received
(HY080)
Interest, dividends, profit from capital investments in incorporated businesses
(HY090)
Interest paid on mortgage
(HY100)
Income received by people aged under 16
(HY110)
Regular taxes on wealth (HY120) Regular inter-hh transfers paid
(HY130)

F

F

F

F

F

F

F

F

F

F

F

 

Cash or near-cash employee income
(PY010)
Other non-cash employee income
(PY020)
Income from private use of company car
(PY021)
Employers social insurance contributions
(PY030)
Cash profits or losses from self-employment
(PY050)
Value of goods produced for own consumption
(PY070)
Unemployment benefits
(PY090)
Old-age benefits
(PY100)
Survivors benefits
(PY110)
Sickness benefits
(PY120)
Disability benefits
(PY130)
Education-related allowances
(PY140)
Gross monthly earnings for employees
(PY200)

L

F

F

F

L

F

F

F

F

NC

F

F

F

 

The source or procedure used for the collection of income variables The form in which income variables at component level have been obtained The method used for obtaining target variables in the required form
Multi sources data collection: survey and administrative data  Individual  Combining survey (collected or imputed) and administrative data
8.2. Comparability - over time

As requested by Eurostat

8.2.1. Length of comparable time series

The number of reference periods in time series are 8 from year 2004 to year 2011, every year four longitudinal component and a cross file are given.

8.3. Comparability - domain

Regional domain comparability are due to weightning calibration and coherence.


9. CoherenceTop
9.1. Coherence - cross domain

Comparison of income target variables and number of persons who receive income from each ‘income component’, with external sources

 

In this section we present the main results of the comparison between IT-SILC data and external data sources for the principal income target variables. In particular, we focus on the following income components: 1) Employee – cash, near cash income, non cash –income (PY010N/G+PY020N/G); 2) Social transfers as the sum of Old-age benefits (PY100N/G), Survival benefits (PY110N/G) and Disability benefits (PY130N/G). Data from National Accounts, Labour Force Survey by Istat, Fiscal Agencies of the Ministry of the Economy and Pensions Register by INPS (National Institute for Social Security) are used as external benchmarks. The table 1 below shows the alignment of total net employee income estimate from IT-SILC respect to the National Accounts aggregate in the year 2010 (the overestimation is below 0.04%). Table 2 shows that the number of employee income earners estimated using IT-SILC approximates the number of employees from Fiscal Agency data (universe of taxable employed income recipients) during 2010.

Differences in applied definitions (i.e. domestic vs resident employment), reference period and coverage of the two data sources can explain well the gap in estimates. By definition, the tax register does not report information on wages and employees arising from the hidden economy, that are only partially included in the survey.

 

Table 1 - Employee income

Economic components:

millions of euro – 2010

National Accounts*

and Fiscal Agencies**

Eu-Silc_11

Gross employee income (cash, near cash, non  cash)                          (PY010G+PY020G)                                      (+)

479,171

480,783

Social contribution paid on

employee income                                          (-)

40,356

42,391

Tax on employee income                              (-)

90,465

89,896

Net employee income  (PY010N+PY020N)

348,350

348,496

 

Table 2 - Employees

Number of people who have received wage and salary (cash or near cash) during 2010

Thousands of units – 2010

Fiscal Agencies**

Eu-Silc_11

 

20,927

21,268

 

Due to lack of harmonization, National Accounts data are not directly comparable with IT-SILC estimates on self-employment incomes.  In table 3 are compared the IT-SILC 2011 estimate of number of self-employment incomes earners with the self-employed of other sources. Notice that in LFS a worker is classified as an independent on the basis of his/her main activity. With respect to NA, the estimate of self-employed units in term of full time equalised workers are presented. The IT-SILC estimate is referred to the number of people whose earnings from self-employment may have been temporary and/or from a secondary working activity.

 

Table 3 – Self-employed

 

Thousands of units – 2010

Number of people who receive cash benefit or losses from self-employment (PY050N)

National Accounts

                  (ula*)

Labour force survey estimate Istat

Eu-Silc_11

 

6,833

5,762

7,797

(*) full time equivalent unit of workers

 

 

Finally, in tables 4 and 5 are reported data on social expenditure and beneficiaries for three kind of functions (ESSPROS) put all together: old-age, survival and disability. In both cases, IT-SILC 2010 estimates are quite close to the administrative data. The closeness of the estimates between IT-SILC and administrative data is due to the massive use of administrative information on the construction of the Eu-Silc target variables: PY100G/N, PY110G/N and PY130G/N.

 

 

 

 

Table 4 – Social benefits payment (old-age, survivors and disability functions)

PY100N-PY110N-Y130N

Millions of euro -  2010

Economic Components:

National Account*  and Fiscal Agencies**

Eu-Silc_11

PY100G-PY110G-PY130G*  (+)

255,467

253,591

Tax on Old-age-Survival-disability benefits** (-)

41,611

41,708

PY100N-PY110N-PY130N***

213,856

211,883

(***) Severance payments  (lump-sum) are excluded

 

Table 5 – Social benefits recipients

 

Thousands – 2010

Number of beneficiaries of Old-age-Survival-disability pensions

Pension Register of INPS*** (excluded persons aged under 15 and/or residing abroad)

Eu-Silc_11

 

16,034

16,423

(***) Severance recipients are excluded

9.1.1. Coherence - sub annual and annual statistics

Not requested by Reg. 28/2004

9.1.2. Coherence - National Accounts

Not requested by Reg. 28/2004

9.2. Coherence - internal

Not requested by Reg. 28/2004


10. Cost and BurdenTop

Not requested by Reg. 28/2004


11. ConfidentialityTop
11.1. Confidentiality - policy

Not requested by Reg. 28/2004

11.2. Confidentiality - data treatment

Not requested by Reg. 28/2004


12. Statistical processingTop
12.1. Source data

The sampling frame is composed by the registers of the municipalities.

 

The sample of the households belonging to the rotational group with DB075=4 was extracted in July 2008 and validated within September 2008.

 

The sample of the households belonging to the rotational group with DB075=1 was extracted in July 2009 and validated within September 2009.

 

The sample of the households belonging to the rotational group with DB075=2 was extracted in July 2010 and validated within September 2010.

 

The sample of the households belonging to the rotational group with DB075=3 was extracted in July 2011 and validated within July 2011, because the survey is a CAPI and the extraction is derived from LAC (the Italian acronym for lists of municipal registry, see http://www.istat.it/it/archivio/16574 ) .

 

The sampling frame is updated in continuous way by the municipalities in interactive modality.

 

12.1.1. Sampling design and procedure
 

Type of sampling design

 

Two stage sampling design: The first stage units (or primary sampling units PSU) are the municipalities, the second stage units (SSU) are the households.

 

The PSU are stratified according to their size in terms of number of residents. Stratification is carried out  inside each administrative region. Four municipalities are selected in each strata.

 

Use of clustering:

Municipalities are clusters of households, households are clusters of individuals.

 

Stratification and sub stratification criteria

 

Stratification of primary sampling units by the number of inhabitants so that the total number of  inhabitants in each stratum is approximately constant (this guarantees  self-weighting design in each region).

Municipalities which sizes are higher than a threshold are self-representing units i.e. are strata themselves and included with certainty in the sample of PSU.

Secondary sampling units are not stratified.

Sample selection schemes


PSU are selected with probability proportional to their size (number of residents) by means of  systematic sampling method by Madow (1949) inside each stratum.

 

Households are selected with equal probability by systematic sampling in each selected municipality from municipality-registers.

 

Sample distribution over time

 

The sample is not distributed over time.

 

Substitution

In Italy no substitution of unit non-response has been applied.

 

 

 

 

 

12.1.2. Sampling unit

Primary sampling units are the municipalities.

Secondary sampling units are the households selected from municipalities’ registers with systematic sampling and not selected with PPS.

 

Sample size (number of SSU)

Number of PSU

Number of SSU (Total)

Avarage number of SSU for each PSU

<25

505

6308

12.5

26-50

353

11756

33.3

51-75

43

2492

58

76-100

13

1127

86.7

101-250

12

1730

144.2

>250

6

2964

494

Total

932

26377

28.3

 

 

12.1.3. Sampling rate and sampling size
 

Concerning the SILC instrument, three different sample size definitions can be applied:

- the actual sample size which is the number of sampling units selected in the sample

- the achieved sample size which is the number of observed sampling units (household or individual) with an accepted interview

- the effective sample size which is defined as the achieved sample size divided by the design effect with regards to the at-risk-of poverty rate indicator

Given that the effective sample size has been already treated in the section dealing with sampling errors, in this section the attention focuses mainly on the achieved sample size.

 

Achieved sample size

 

num_of_hh2010

num_of_hh2011

perc1

persons_16_over2011

last_rot_gr

num_of_rot_hh2011

perc2

19147

19399

1.01

40496

1

4255

21.93

 

DB075

 

DB135

Number of households for which the interview is accepted

number of persons of 16 years or older by type of interview

 

 

1

 

 

1

N

4255

5452

8981

 

%

21.93

20.88

22.18

2

N

4189

5517

8689

 

%

21.59

21.12

21.46

3

N

6748

9923

13873

 

%

34.79

38

34.26

4

N

4207

5224

8953

 

%

21.69

20

22.11

Totale

N

19399

26116

40496

%

100

100

100

 

12.2. Frequency of data collection

Fieldwork 

The total duration of the data collection of the sample

 

start_day

start_month

end_day

end_month

1

9

31

12

 

Renewal of sample: rotational groups

 

Rotational design is used for households; the whole sample is composed of four rotational groups. Each group is included in the sample for four waves of the survey. Each year one fourth of the sample is renewed, replacing the group entered in the sample four years before.

 

 

A

B

C

D

E

F

G

H

I

T

A4

B3

C2

D1

 

 

 

 

 

T+1

 

B4

C3

D2

E1

 

 

 

 

T+2

 

 

C4

D3

E2

F1

 

 

 

T+3

 

 

 

D4

E3

F2

G1

 

 

T+4

 

 

 

 

E4

F3

G2

H1

 

T+5

 

 

 

 

 

F4

G3

H2

I1

 

Each group is associated to one municipality of the strata. The self-representative municipalities are enclosed in each of the rotational groups: in such case the households referring to these municipalities are divided in 4 independent samples.

 

12.3. Data collection
 

Mode of data collection

A description of the mode of data collection used in your country. Please mention if you use mixed mode of data collection.

1-PAPI
(% of total)
2-CAPI
(% of total)
3-CATI
(% of total)
4-Self administrated
(% of total)
 0.0  100.0  0.0  0.0


Alternative Table for Mode of data collection 

  

Systematic process of gathering data for official statistics

 

 

Proxy

(% of total)

1-PAPI

2-CAPI

 

X

data

 

X data

 

X data

 

2010

19

 

100

 

 

 

2011

23.9

 

 

 

100

 

 

 



The mean interview duration

The mean interview duration per household is calculated as the sum of the duration of all household interviews plus the sum of the duration of all personal interviews, divided by the number of household questionnaires completed. Only households accepted for the database have to be considered.

 

Average interview duration = 40.5 minutes

12.4. Data validation

Not requested by Reg. 28/2004

12.5. Data compilation

Not requested by Reg. 28/2004

 

 

 

12.5.1. Weighting procedure
 

Design factor

Non-response adjustments

Adjustment to external data

Final cross sectional weights

 

Wave 1;

In case of the households at the first wave, the design weight of each household was given by the inverse of its inclusion probability and was calculated taking into account the population of the stratum, the population and the number of households in the extracted municipalities. In every stratum it is extracted one municipality.

Let  pji  be the design weight  of the generic household  j in the municipality i:

                    pji  =1 /πhi=Ph / Phi  * Mhi/mhi
                                                                                                               

where :

h              is the stratum index;

i               is the municipality index;

πhi   is the inclusion probability of the households resident in the municipality i of the stratum h;

Ph            is the population resident in the stratum h;

Phi           is the population in the municipality i of the stratum h;

Mhi          is the number of households resident in the municipality i of the stratum h;

mhi           is the number of sample households in the municipality i of the stratum h.

 

Wave 2, 3, 4;

In case of the households at the second, third or fourth wave, an indirect sampling of households is done through the panel of persons aged 14+ at the time of the panel selection. In this case, the inclusion probabilities cannot be calculated. Then, the solution consists of applying the Weight Share Method. Within a household, each member has been assigned a weight coming from the final cross-sectional weight of the precedent year of survey corrected for unit non-response, except for co-residents form whom the weight is =0. Average of these weights over all the household members (including co-residents) is assigned to each member (including co-residents).

 

In the sample we observe two different non-response level: individual-level and household-level.

Concerning with the individual-level non-response, the records of the non-respondent individual belonging to respondent households were totally imputed.

Concerning with the non-response adjustment at the household level, the base weights were adjusted by a correction factor for total non-response worked out as the reciprocal of the response probability for each household identified by the information we had on the extracted sample (for the households at wave 1) or gathered from the previous year of survey (for the households at wave 2, 3, 4). The response probability is obtained by a logistic regression model.

The re-calculated weight pj(circumflex) for the generic household j is:

p(circumflex)=pjj  , where pj  the design weight and  πj is the response probability.

 

Wave 1: the information used for the “new” households are:

territorial domain (NUTS II level), demographic size of the municipalities, number of household components and sex, age and nationality of the householder (gathered from demographic registers).

Wave 2, 3, 4: the information used for the “old” households are:

territorial domain (NUTS II), demographic size of the municipalities, number of household components, type of income sources, tenure status, rotational group, household disposability to the interview in previous year, nationality, sex, age, education of the household components.

In conformity with the previous year of survey a first stage of calibration procedure was adopted to assure the same structure as the population of the Labour Force Survey with regard to the education and professional position of the population. This is due to the fact that in Italy the non-response in an income survey is correlated with the position in the labour market (especially for self-employed) and with the education level of the respondents.

 

After the non-response adjustments, the final weights were obtained applying a calibration of the household weights to external data sources (registers). Let X1, X2…Xp denote the external (known) variables

 The calibration procedure consists of calculating the household weights ψj, such as:

- The calibrated weights are “not very different” from the weights pj(circumflex)

- The totals Xr of the calibration variables are exactly estimated by the same totals in the sample obtained with the weights ψ.

 

The external known totals are the following:

 

For the entire sample:

1) Distribution of the population by sex and fourteen 5-years age-groups at NUTS I level (year t-1). The age groups are: 0-15, 16-19, 20-24, 25-29, 30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64, 65-69, 70-74, 75+ at the end of the income reference period (year t-1);

2) Distribution of the population by sex and five age-groups at NUTS II level (year t-1). The age groups are: 0-15, 16-25, 26-45, 46-65, 65+ at the end of the income reference period (year t-1).

3) Distribution of non-national population at NUTS I level by sex; by age in two classes: 0-17, 18+ at the end of the income reference period (year t-1).

4) Distribution of the population by demographic size of the municipality at Nuts I level (year t-1) (six classes).

5) Number of households at NUTS II level at the time of the survey (year t); Number of households with non-national components at NUTS I level (year t).

 

For the entering rotational sub-group (at first wave):

1) Distribution of the population by sex and five age-groups at NUTS I level. The age groups are: 0-15, 16-25, 26-45, 46-65, 65+ at the end of the income reference period (year t-1).

2) Amount of non-national population at NUTS I level distinct in two classes: 0-17, 18+ at the end of the income reference period (year t-1).

 (year t-1).

3) Distribution of the population by demographic size of the municipality at Nuts I level (year t-1) (three classes).

4) Number of households at NUTS I level at the time of the survey (year t)                                                                 

 

For the other sub-groups:

1) Population at NUTS I level (year t-1)

2) Number of households at NUTS I level (year t);

 

We applied an integrative calibration, that means that we used both household and personal variables in the procedure. The calibration is performed at household level using the household variables and the individual variables in their aggregate form as calibration variables. This technique ensures that members in the same household all receive the same weight. A trimming procedure was applied to avoid extreme values of weights.

 

12.5.2. Estimation and imputation
 
Imputation procedure used Imputed rent Company car
  Objective, hedonic regression or Heckman method  

To assign the value to the variable “company car” ACI tables are used, according to the model of car and the year of registration. When the informations about model and car registration are missing, it is used the value stated in the time t-1 (for ¾ of the sample, to say the “re-interviewed”).

12.6. Adjustment

The set of procedures employed to modify statistical data to enable it to conform to national or international standards or to address data quality differences when compiling specific data sets are applied at the end of the weighting procedure, after the non-response adjustments.

The external known totals are the following:

 For the entire sample:

1) Distribution of the population by sex and fourteen 5-years age-groups at NUTS I level (year t-1). The age groups are: 0-15, 16-19, 20-24, 25-29, 30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64, 65-69, 70-74, 75+ at the end of the income reference period (year t-1);

2) Distribution of the population by sex and five age-groups at NUTS II level (year t-1). The age groups are: 0-15, 16-25, 26-45, 46-65, 65+ at the end of the income reference period (year t-1).

3) Distribution of non-national population at NUTS I level by sex; by age in two classes: 0-17, 18+ at the end of the income reference period (year t-1).

4) Distribution of the population by demographic size of the municipality at Nuts I level (year t-1) (six classes).

5) Number of households at NUTS II level at the time of the survey (year t); Number of households with non-national components at NUTS I level (year t).

 

For the entering rotational sub-group (at first wave):

1) Distribution of the population by sex and five age-groups at NUTS I level. The age groups are: 0-15, 16-25, 26-45, 46-65, 65+ at the end of the income reference period (year t-1).

2) Amount of non-national population at NUTS I level distinct in two classes: 0-17, 18+ at the end of the income reference period (year t-1).

 (year t-1).

3) Distribution of the population by demographic size of the municipality at Nuts I level (year t-1) (three classes).

4) Number of households at NUTS I level at the time of the survey (year t)                                                                 

 

For the other sub-groups:

1) Population at NUTS I level (year t-1)

2) Number of households at NUTS I level (year t);


13. CommentTop

All the Ad-hoc Module variables are fully comparable.


AnnexesTop