Understanding and combating nonresponse Michel Philippens (KU Leuven) Achim Koch (ZUMA, Mannheim) Measuring attitudes and values in Europe: The contribution of the European Social Survey Brussels, November 2003
Types of nonresponse Non-contacts Refusals Others: illness / language problems Effects of nonresponse Reduction in final sample size (Potentially) nonresponse bias Increase in costs Response rate target in ESS: 70 percent
Dealing with the issue of nonresponse in the ESS target response rate fieldwork procedures Specification of a high target response rate / insisting on certain fieldwork procedures survey organisations contractual obligation High quality survey organisations should be selected / high response rates as a contractual obligation monitoring reports Close monitoring of progress during fieldwork period / fortnightly reports on response Standardized documentation aggregate individual level Standardized documentation of fieldwork / data on the aggregate and on the individual level
Type of survey organisation Basic information on fieldwork - 1
Mode of interviewing: PAPI vs. CAPI Basic information on fieldwork - 2
Basic information on fieldwork - 3 Length of fieldwork period Average length: 106 days 60 days or less: 3 countries Hungary (28) Slovenia (44) Greece (45) days: 8 countries Denmark (66) Poland (80) Sweden (88) Finland (92) Israel (92) Spain (93) Czech Republic (105) Portugal (116) 121 days or more: 8 countries Ireland (122) Luxembourg (122) Norway (123) United Kingdom (133) Switzerland (152) Italy (168) Netherlands (176) Germany (177)
Basic information on fieldwork – 4 Costs per interview Estimate Blueprint: 105 Euro (excl. VAT) Information from contracts: 125 Euro (incl. VAT) Sweden 262 Netherlands 229 Norway 223 United Kingdom 179 Denmark 176 Switzerland 171 Germany 156 Spain 125 Italy 63 Portugal 45 Slovenia 45 Poland 28 Czech Republic 27 Hungary 18 No information available: Finland, Greece, Ireland, Israel, Luxembourg (in Euro, including VAT)
Fieldwork outcomes – 1 Achieved number of interviews 13 countries meeting the sample size requirement: Germany (2995) Greece (2566) Israel (2499) Netherlands (2364) Poland (2110) United Kingdom (2052) Ireland (2046) Switzerland (2041) Norway (2036) Finland (2000) Sweden (1999) Luxembourg*(1553) Slovenia* (1519) 6 countries not meeting the sample size requirement: Because of budgetary constraints Spain (1729) Hungary (1685) Portugal (1511) Denmark (1506) Because of low response rates Czech Republic (1360) Italy (1207) *Population of less than 2 million
Fieldwork outcomes – 2 Achieved response rates (in %) Greece 80.0 Finland 73.2 Poland 73.2 Israel 71.0 Slovenia 70.5 Hungary 69.9 Sweden 69.5 Portugal 68.8 Netherlands 67.9 Denmark 67.6 Norway 65.0 Ireland 64.5 Germany 57.1 United Kingdom 55.5 Spain 53.2 Luxembourg 43.9 Italy 43.7 Czech Republic 43.3 Switzerland 33.5