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On cost efficiency- Tracking and tracing in the Norwegian EU-SILC

Are the benefits from achieving one more respondents worth the effort?

Bengt Oscar Lagerstrøm, Statistics Norway

Paper presented at q2014, Vienna

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Motivation 1

2006 2007 2008 2009 2010 2011 2012 20130

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60

70

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Response rate EU-SILC 2006-13

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Motivation 2

• Non-response in itself is not a good measure of non-response errors (Curtin, Presser and Singer 2000, Groves and Dipko 2004).

• Heerwegh, Abts and Loosveld (2007) show that although the non-response rate is higher than the non-contact rate, the proportion of non-response error is significantly larger due to non-contact than to refusal.

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Steinsson and Lagerstrøm (2010)

• Non-response in current wave under-estimates social indicators (Gini-index, at-risk-of-poverty, S80/S20)

• Drop outs in the next wave has higher social indicators then respondents in both current wave and the next wave.

• Both drop-outs and late respondent have higher variation in their income distribution

• Non-response under estimates the income distribution in both Iceland and Norway and higher non-response rates increase the difference

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Karlsson, Jónasdóttir and Lagerstrøm (2013)• Manual tracing of telephone numbers increase the

representativeness (age under 45, single households, non-natives)

• Only minor effects on a large set of indicators (Norway)

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Contact rate, cooperation rate and response rate after source of telephone number. 2012

Contact rate Cooperation rate Response rate

Working numbers without errors (automated) 0,874 0,724 0,632776

Working numbers with errors (automated) 0,845 0,437 0,369265

Manual traced numbers 0,718 0,651 0,467418

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Contact rate after number of calls after different types of numbers. 2012

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Numbers of calls (events)

Conta

ct

rate

(%

)

Working numberswith errors

Manual tracednumbers

Working numberswithout errors(automated)

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Distribution of time use

  Interview Contact and recruiting

Working numbers

without errors (automated) 85.8 74.4

Working numbers

with errors (automated) 8.5 15.8

Manual traced

numbers 5.8 9.8

3,124 (31.2) 6,876 (68.8)

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Contact and recruiting hours and costs per completion (mean). 2012

  CRHPC (min) CRHPC (€) Ratio (€)

Working numbers

without errors

(automated) 57 31.35  

Working numbers

with errors

(automated) 124 68.20 0.4597

Manual traced

numbers 128 70.40 0.4453

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New strategy to improve effect of tracing and reduce cost due to no contact

– Increase efforts to identify non-effective numbers Monitoring of the call-history during data collection Maximum call-bakcs on a lower level Interviewers

– Increase efforts to ensure effective tracing Identify effective tracing procedures centralized tracers

– Increase use of new sources for telephone numbers Administrative registers