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Erschienen in: Quality & Quantity 4/2014

01.07.2014

Survey topic and unit nonresponse

Evidence from an online survey on mating

verfasst von: Doreen Zillmann, Andreas Schmitz, Jan Skopek, Hans-Peter Blossfeld

Erschienen in: Quality & Quantity | Ausgabe 4/2014

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Abstract

Survey topic as a factor influencing participation rates is becoming increasingly important, as there is a growing trend in social science research for surveying specific populations about specific topics. Previous research has shown that respondents with high topic interest (often referred to as salience) are more likely to participate in surveys. However, the identification of mechanisms that affect respondents’ interest in a survey topic has been largely neglected in research literature. We present an explanatory model of participation that conceptualizes topic interest as a function of an actor’s relational position in a particular social setting. To illustrate the relationship between survey topic and participation behavior, we use an online survey on mating conducted on the user population of an online dating site. For our nonresponse analysis we use web-generated process data, consisting of profile and interaction data, which describe all units of the sample frame. Thus, comprehensive information is available for both participants and non-participants of the online survey on an individual level, enabling a particularly accurate analysis of nonresponse. Results show that the probability of participation varies according to a user’s chances of success on the mating market. Users who can be described as less attractive (e.g. older people, less educated men, overweight women) show a higher probability of participation, which we explain with the mechanism of topic salience. We conclude with general implications regarding (1) the relationship between survey topic and survey participation and (2) the potential of web-generated process data for (online) survey research.

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1
One exception here is an experimental study by van Kenhove et al. (2002), which measured both respondents’ and non-respondents’ interest in and importance of the survey topic directly.
 
2
A user was considered to be active when he or she had logged onto the website within the last six months, with the reference point being the start of the survey.
 
3
These were user profiles which had been deleted before receiving the invitation, administrator profiles, and profiles whose attributes seemed impossible or implausible (so-called “gimmick accounts”). We define these profiles as sample-neutral drop outs because these users are not part of the survey’s target population, as it seems unlikely that they are looking for a partner.
 
4
The website’s terms and conditions informed users of the collaboration with the university. It was explained that the collaboration involved profile and interaction data being passed on in anonymized form under the supervision of the company’s data protection administrator. The data were given to the university for scientific purposes only, namely the analysis of mate selection behavior. Users could opt out of their data being used.
 
5
We selected this indicator (RR2, not RR1, based on AAPOR standard definitions) because our analysis of dropout focuses on unit nonresponse, and therefore on the question of self-selection into the survey. The problems of item nonresponse and survey dropout (which we have shown is fairly marginal) are not our focus. However, we also carried out the analyses with survey completion as dependent variable (AAPOR standard RR1). This did not substantially alter our results; in fact, the tendencies we observed were actually stronger in some cases.
 
6
We based our descriptions of a user’s educational level on the work of Blossfeld and Timm (1997, 2003). This gave us the following hierarchy: in training: still at school / vocational training; low educational level: (1) no general educational qualifications, (2) general secondary education without vocational training, (3) intermediate secondary education without vocational training; medium educational level: (1) general secondary education as well as vocational training, (2) intermediate secondary education as well as vocational training, (3) higher education entrance qualification (e.g., Abitur) without and (4) with vocational training; high educational level: (1) lower tertiary (e.g., university of applied sciences), (2) higher tertiary (e.g., academically oriented university education), or (3) PhD.
 
7
The analyses are primarily based on user self-reports. As with any data source dependent on self-reports, there are questions concerning the validity of the data. We excluded profiles with highly unlikely or implausible information from the nonresponse analysis. More difficult is detecting the less obviously false information in user profiles. Previous analyses have shown that, although there is a certain level of deception in online dating user profiles, the magnitude of deception is quite small, and therefore close to the true value (cf. Toma et al. 2008; Zillmann et al. 2011; Skopek 2011). These small deviations within user profiles should not change our results substantially.
 
8
The completion indicator consists of the following 16 variables: gender, desired partner gender, date of birth, school qualifications, vocational qualifications, desired relationship, marital status, height, weight, figure, hair color, eye color, whether the user wants children, whether the user has children, whether the user is a smoker, and whether a partner smoking is undesirable.
 
9
Applying the indicator of profile incompleteness has a significant influence on the effects of missing data for each individual profile variable, but not on the effect of the other attributes. Table 5 in the appendix gives the multivariate results without the indicator for missing profile data. Due to suspected multicollinearity within the missing indicators of each variable and between the missing indicators and the general propensity to item nonresponse we also specified a model not reported here. The covariance of all missing indicators was modeled with a common latent factor “propensity to item nonresponse”, which served as a substitute for the additive index as specified in the model reported in Table 2. However, as this alternative structural equation model yielded almost the same regression parameters while being less sparse, we decided to report the regression model in Table 2 only.
 
10
One may argue that there is another interpretation possible (separate from the hypotheses on success chances) which may be particularly valid for the effect of education among men, and the effect of age for both genders: we may not be recording an effect of potential success, but an effect of available time resources. That is, there may be an increased likelihood of participation among those users who have more free time, perhaps because they are currently unemployed, or because their children may have moved out of the family home. However, we can exclude a possible time effect because we control for website activity, which indicates time investments in finding a partner. In additional analyses, not reported here, we also controlled for employment (i.e., if a user worked part or full time, or if they were unemployed, retired etc.). Our results remained stable when we controlled for employment; we therefore conclude that our findings can clearly be interpreted as an effect of success chances, rather than as a differential time effect for various population groups.
 
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Metadaten
Titel
Survey topic and unit nonresponse
Evidence from an online survey on mating
verfasst von
Doreen Zillmann
Andreas Schmitz
Jan Skopek
Hans-Peter Blossfeld
Publikationsdatum
01.07.2014
Verlag
Springer Netherlands
Erschienen in
Quality & Quantity / Ausgabe 4/2014
Print ISSN: 0033-5177
Elektronische ISSN: 1573-7845
DOI
https://doi.org/10.1007/s11135-013-9880-y

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