# **<mark>1. Introduction</mark>**

<mark>Internet-based surveys are a convenient option for policy makers and research organizations to collect data in a cost-effective way. Online surveys present many advantages. First, it is possible to achieve large sample sizes in a short amount of time, enabling the tracking of frequently changing events. This would enable policy makers to collect survey data more frequently on key policy indicators. Second, with the increased spread of the Internet, online surveys can be substantially more cost-effective than regular physical surveys in reaching out to more respondents. Third, the anonymity of respondents makes it possible to ask extremely sensitive questions, garner honest responses, and maintain the respondent’s safety, which could otherwise be difficult in face-to face or phone surveys (Braunsberger et al. 2007; Granello and Wheaton 2004).</mark> <mark>The COVID-19 pandemic curtailed economic activities worldwide and adversely affected labor market participation. These changes were abrupt and ever-evolving due to the unpredictable nature of the pandemic, which also in many countries prevented the implementation of face-toface surveys. In such a setting, internet surveys are a potentially attractive option for tracking the frequently changing economic situation.</mark> <mark>The main disadvantage of online surveys is that they are typically based on non-probabilitybased sampling techniques. Respondents are selected based on convenience and internet access rather than at random from a census-based sample frame.</mark><sup>1</sup> <mark>Online surveys are not nationally representative because some individuals in the target population may not have access to the internet, those with internet access may be more or less likely to be approached for a survey, and not all of those who are approached may respond to the survey. Since the probability of inclusion in the sample depends on respondent characteristics, the resulting sample is prone to selection bias. A large literature corroborates this evidence on the lack of representativeness of online surveys (e.g., Evans and Mathur 2005; Granello and Wheaton 2004; Steinmetz and Tijdens 2009; Steinmetz et al. 2014; Steinmetz, Tijdens, and de Pedraza 2009; Valliant and Dever 2011). Despite these issues, surprisingly, many surveys continue to be conducted online, for example, through river sampling (American Association for Public Opinion Research 2013), and many opinion polls continue to be conducted using nonprobability online panels</mark> <u><mark>(Callegaro, Villar, Yeager, and Krosnick 2014a; Callegaro, Baker, Bethlehem, Göritz, Krosnick, Lavrakas, 2014b).</mark></u> <mark>In comparison with Internet surveys, other modes of data collection have different strengths and weaknesses. Random Digit Dialing (RDD) phone surveys and traditional face-to-face surveys are common and more traditional alternatives. RDD is a method of probability sampling that provides a sample of households, families, or persons through a random selection of their telephone numbers. Since RDDs rely on the frame of those who own a phone, and not on the whole population, they may not be nationally representative. Biases can also arise based on the person who answers the phone call, because interviewers and respondents sometimes rush through conversations, and due to non-responses arising from network non-availability or other reasons (Holbrook et al. 2003).</mark><sup>2</sup> <mark>From the perspective of those requesting the survey, online</mark>

> 1 Increasingly, many companies are trying to conduct Internet surveys with a frame from which probability samples can be drawn (e.g., Kapteyn, Smith, and van Soest 2007; Malhotra and Kuo 2008; Moskalenko and McCauley 2009; Skitka and Bauman 2008), but these are rare because it is hard to develop a frame without knowledge of the universe of Internet users. 2 For example, Kohut et al. (2012) shows that RDD response rates decreased from 36% in 1997 to 9% in 2012.

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