Peter Lynn
Biographic Data
| ID | 175199 |
|---|---|
| NAME | Peter Lynn |
| GIVEN NAMES | Peter |
| FAMILY NAME | Lynn |
| SIGNATURE | LYNN P |
| AFFILIATIONS | University of Essex |
| ORCID | 0000-0002-3493-5686 |
| VERIFIED | Yes |
| TOTAL WORKS | 26 |
| TOTAL CITATIONS | 88 |
| AUTHOR COUNT | 23 |
| EDITOR COUNT | 3 |
| FIRST PUBLICATION YEAR | 1994 |
| LATEST PUBLICATION YEAR | 2025 |
| H-INDEX | 6 |
Benefits of increasing the value of respondent incentives during the course of a longitudinal mixed-mode survey
This paper explores the effects of increasing the value of survey incentives on response rates and fieldwork efforts using data from a large-scale randomised experiment embedded in wave 12 of a national probability-based longitudinal survey. We also investigate whether effects differ between previous-wave respondents, who were sent an unconditional incentive, and previous wave non-respondents, who were offered a conditional incentive. The treatme…
How to design and implement surveys that are fit for purpose
Text Messages to Incentivise Response in a Web-First Sequential Mixed-Mode Survey
This article reports research exploring the benefits of adding text messages to the contact strategy in the context of a sequential mixed-mode design where telephone interviewer administration follows a web phase. In a web-first mixed-mode survey, supplementing the contact strategy with text messages can help increase the response rate at the web phase and, consequently, reduce fieldwork efforts at the interviewer-administered phase. We present r…
The Impact of day of Mailing on Web Survey Response Rate and Response Speed
The day of the week on which sample members are invited to participate in a web survey might influence propensity to respond, or to respond promptly (within two days from the invitation). This effect could differ between sample members with different characteristics. We explore such effects using a large-scale experiment implemented on the Understanding Society Innovation Panel, in which some people received an invitation on a Monday and some on …
Advances in Longitudinal Survey Methodology
Generalization of Classic Question Order Effects Across Cultures
Questionnaire design is routinely guided by classic experiments on question form, wording, and context conducted decades ago. This article explores whether two question order effects (one due to the norm of evenhandedness and the other due to subtraction or perceptual contrast) appear in surveys of probability samples in the United States and 11 other countries (Canada, Denmark, Germany, Iceland, Japan, the Netherlands, Norway, Portugal, Sweden, …
Item Nonresponse Rates and Panel Conditioning in a Longitudinal Survey among Youth
The article examines two important aspects of data quality in self-completion surveys of young people, taking advantage of a unique data source: Understanding Society: the United Kingdom Household Longitudinal Study. Young persons aged 10–15 are asked to complete a self-administered paper questionnaire at annual intervals. The number of completed interviews varies over waves from 4,049 to 5,020. Data are also collected from parents, providing imp…
Applying Prospect Theory to Participation in a Capi/Web Panel Survey
Prospect theory states that the influential power of avoiding negative outcomes is stronger than that of achieving positive outcomes. In a survey context, this theory has been tested with respect to not only participation in a CATI survey, but also giving consent to data linkage in CATI surveys. No study, however, has tested the theory with respect to participation in a CAPI or web survey. This study does so in a mixed-mode panel context; it also…
Design and implementation of a high-quality probability sample of immigrants and ethnic minorities
Surveys of immigrants face challenges of coverage, representativeness, and response rates. Longitudinal studies of immigrants and ethnic minorities, which have potential to address pressing issues in demographic research, are rare or partial. In the absenc
The Role of E-mail Communications in Determining Response Rates and Mode of Participation in a Mixed-mode Design
This article is concerned with the extent to which the propensity to participate in a web face-to-face sequential mixed-mode survey is influenced by the ability to communicate with sample members by e-mail in addition to mail. Researchers may be able to collect e-mail addresses for sample members and to use them subsequently to send survey invitations and reminders. However, there is little evidence regarding the value of doing so. This makes it …
Targeted Appeals for Participation in Letters to Panel Survey Members
Previous research into survey invitation letters and prenotification letters has sought to identify optimal features of a standard letter that can be sent to all sample members. In the spirit of adaptive design, this study seeks to establish whether it can be advantageous to target different versions of a letter to different sample subgroups. Specifically, a paragraph intended to heighten perceptions of relevance of the survey is varied among six…
The Problem of Nonresponse
Many books about survey sampling tell you how the precision of survey estimates depend on the sample design. However, this assumes that data are obtained for every unit in the selected sample. This is rarely the case; most surveys experience some nonresponse. This can affect the survey estimates. This chapter aims to explain how and why nonresponse occurs, why it is important, and what can be done to minimize any undesirable consequences, either …
Methods for Probability-Based Online and Mixed-Mode Panels
This special issue is devoted to discussion of probability-based survey panels that collect data either solely or partly through online questionnaires. Panels of this kind have been around for a long time, though they have been few in number, but recent years have seen several new panels start up in Europe. This has led to renewed interest in the methodology of such panels and also to deeper questioning of the role of these panels. On one hand, t…
Using Motivational Statements in Web-Instrument Design to Reduce Item-Missing Rates in a Mixed-Mode Context
Journal Article Using Motivational Statements in Web-Instrument Design to Reduce Item-Missing Rates in a Mixed-Mode Context Get access Tarek Al Baghal, Tarek Al Baghal * *Address correspondence to Tarek Al Baghal, ISER, University of Essex, Wivenhoe Park, Colchester, Essex UK CO4 3SQ; e-mail: [email protected]. Search for other works by this author on: Oxford Academic Google Scholar Peter Lynn Peter Lynn Tarek Al Baghal is a senior research offi…
Improving Survey Methods
Invited talks were given by Jelke Bethlehem (Statistics Netherlands), Don Dillman (Washington State University), and Peter Lynn (University of Essex). The second conference entitled “Advancing Survey Methods” was held two years later in
Longer Interviews May Not Affect Subsequent Survey Participation Propensity
Survey researchers often assume that respondent burden is an important determinant of survey participation propensity and that interview length is a good indicator of burden. However, there is surprisingly little evidence of the effect of length of a completed interview on subsequent participation propensity, particularly in the case of face-to face surveys. This article presents results from a large-scale randomized experiment in which responden…
Extended Field Efforts to Reduce the Risk of Non-response Bias
We examine the effects on survey estimates of extended interviewer efforts to gain survey response, including refusal conversion attempts and attempts to make contact with difficult-to-contact sample members. Previous research on this topic has identified that extended efforts do appear to affect estimates, and in ways that seem consistent with bias reduction. We extend the previous research in three ways. First, we provide the first study of cha…
The Impact of Mobile Phones on Survey Measurement Error
We propose a framework of ways in which the different context of mobile interviews-such as multi-tasking, distraction, and the presence of others-and differences inherent in the technology can influence survey responses. The framework also highlights the mechanisms through which these influences operate. We evaluate selected elements of the framework using data from a randomized experiment in which respondents were interviewed by mobile or landli…
It Is Time Computers Do Clever Things
Despite the increased interest in assessing the effects of dependent interviewing (DI) on data quality, the impact of DI on interviewer burden and interviewer-respondent interaction remains currently unexplored and undocumented. Drawing on Japec's work, this article attempts to evaluate the impact of DI on interviewer burden and describes the mechanisms by which DI affects perceived interviewer burden and ultimately data quality. We use a diverse…
Methodology of Longitudinal Surveys
In this chapter, our focus is on panel conditioning with respect to attitude questions. Our methodological approach is different from the majority of previous studies in this area, in that we do not attempt to estimate biases in marginal and associational distributions through comparison with a fresh cross-sectional sample. Rather, our approach is based on testing hypotheses on a single dataset, derived from an explicit theoretical model of the p…
The Feasibility of linking household survey and administrative record data
Linkage of household survey responses with administrative data is increasingly on the agenda. Unique individual identifiers have clear benefits for making linkages but are also subject to problems of survey item non-response and measurement error. Our experimental study that linked survey responses to UK government agency records on benefits and tax credits elucidates this trade-off. We compare five linkage criteria: one based on a respon-dent-su…
The International Conference on Methodology of Longitudinal Surveys (Mols), 12-14 July 2006
La conférence internationale sur la méthodologie des enquêtes longitudinales : Du 12 au 14 juillet 2006, à l'université d'Essex, Peter Lynn, avec le « UK Longitudinal Studies Centre » et l'« International Association of Survey Statisticians » (IASS), a organisé la conférence internationale sur la « Methodology of Longitudinal Surveys » (MOLS 2006). Le BMS a rassemblé des matériaux des sites Web de MOLS 2006 et de l'« International Statistical Ins…
Measuring Change in Employment Characteristics
We have demonstrated that the use of PDI results in lower levels of observed change in each of a number of characteristics of the respondent's employment. The reduction in observed change is particularly pronounced for SOC, SIC, and the number of employees at the respondent's workplace. This reduction in observed change appears to represent a reduction in measurement error as the effect of PDI is particularly pronounced amongst respondents who ha…
Developing quality standards for cross-national survey research
This paper addresses methods for the development of quality standards for cross-national quantitative surveys. Five conceptual approaches to the development of standards are presented and the properties and consequences of each are discussed. The aim is to provide researchers with a rational set of arguments for choosing a particular approach in a given situation. The development of quality standards is particularly complicated in the case of cro…
The British Crime Survey Sample
In this journal, Elliott and Ellingworth (1997)reported their attempts to assess the impact of certain sources of survey error on the British Crime Survey. This article attempts to correct some flaws in their article, to place their results in a wider context, and to provide some further - arguably more robust - estimates of the impact of non-response bias
The Impact of Mobile Phones on Survey Measurement Error
We propose a framework of ways in which the different context of mobile interviews-such as multi-tasking, distraction, and the presence of others-and differences inherent in the technology can influence survey responses. The framework also highlights the mechanisms through which these influences operate. We evaluate selected elements of the framework using data from a randomized experiment in which respondents were interviewed by mobile or landli…
Methods for Probability-Based Online and Mixed-Mode Panels
This special issue is devoted to discussion of probability-based survey panels that collect data either solely or partly through online questionnaires. Panels of this kind have been around for a long time, though they have been few in number, but recent years have seen several new panels start up in Europe. This has led to renewed interest in the methodology of such panels and also to deeper questioning of the role of these panels. On one hand, t…
Targeted Appeals for Participation in Letters to Panel Survey Members
Previous research into survey invitation letters and prenotification letters has sought to identify optimal features of a standard letter that can be sent to all sample members. In the spirit of adaptive design, this study seeks to establish whether it can be advantageous to target different versions of a letter to different sample subgroups. Specifically, a paragraph intended to heighten perceptions of relevance of the survey is varied among six…
Measuring Change in Employment Characteristics
We have demonstrated that the use of PDI results in lower levels of observed change in each of a number of characteristics of the respondent's employment. The reduction in observed change is particularly pronounced for SOC, SIC, and the number of employees at the respondent's workplace. This reduction in observed change appears to represent a reduction in measurement error as the effect of PDI is particularly pronounced amongst respondents who ha…
Developing quality standards for cross-national survey research
This paper addresses methods for the development of quality standards for cross-national quantitative surveys. Five conceptual approaches to the development of standards are presented and the properties and consequences of each are discussed. The aim is to provide researchers with a rational set of arguments for choosing a particular approach in a given situation. The development of quality standards is particularly complicated in the case of cro…
Using Motivational Statements in Web-Instrument Design to Reduce Item-Missing Rates in a Mixed-Mode Context
Journal Article Using Motivational Statements in Web-Instrument Design to Reduce Item-Missing Rates in a Mixed-Mode Context Get access Tarek Al Baghal, Tarek Al Baghal * *Address correspondence to Tarek Al Baghal, ISER, University of Essex, Wivenhoe Park, Colchester, Essex UK CO4 3SQ; e-mail: [email protected]. Search for other works by this author on: Oxford Academic Google Scholar Peter Lynn Peter Lynn Tarek Al Baghal is a senior research offi…
Design and implementation of a high-quality probability sample of immigrants and ethnic minorities
Surveys of immigrants face challenges of coverage, representativeness, and response rates. Longitudinal studies of immigrants and ethnic minorities, which have potential to address pressing issues in demographic research, are rare or partial. In the absenc
Longer Interviews May Not Affect Subsequent Survey Participation Propensity
Survey researchers often assume that respondent burden is an important determinant of survey participation propensity and that interview length is a good indicator of burden. However, there is surprisingly little evidence of the effect of length of a completed interview on subsequent participation propensity, particularly in the case of face-to face surveys. This article presents results from a large-scale randomized experiment in which responden…
The Feasibility of linking household survey and administrative record data
Linkage of household survey responses with administrative data is increasingly on the agenda. Unique individual identifiers have clear benefits for making linkages but are also subject to problems of survey item non-response and measurement error. Our experimental study that linked survey responses to UK government agency records on benefits and tax credits elucidates this trade-off. We compare five linkage criteria: one based on a respon-dent-su…
Place, Personal Characteristics and Councillor Roles
The government proposals on the structure and internal management of local government put forward in 1991 raise important questions for the representative and decision-making roles of councillors. A re-analysis of data collected for the Widdicombe committee in 1985 was conducted, using multiple regression. The findings suggest that the time councillors spend on different council activities is significantly affected by a number of locality variabl…
Extended Field Efforts to Reduce the Risk of Non-response Bias
We examine the effects on survey estimates of extended interviewer efforts to gain survey response, including refusal conversion attempts and attempts to make contact with difficult-to-contact sample members. Previous research on this topic has identified that extended efforts do appear to affect estimates, and in ways that seem consistent with bias reduction. We extend the previous research in three ways. First, we provide the first study of cha…
Benefits of increasing the value of respondent incentives during the course of a longitudinal mixed-mode survey
This paper explores the effects of increasing the value of survey incentives on response rates and fieldwork efforts using data from a large-scale randomised experiment embedded in wave 12 of a national probability-based longitudinal survey. We also investigate whether effects differ between previous-wave respondents, who were sent an unconditional incentive, and previous wave non-respondents, who were offered a conditional incentive. The treatme…
The Impact of day of Mailing on Web Survey Response Rate and Response Speed
The day of the week on which sample members are invited to participate in a web survey might influence propensity to respond, or to respond promptly (within two days from the invitation). This effect could differ between sample members with different characteristics. We explore such effects using a large-scale experiment implemented on the Understanding Society Innovation Panel, in which some people received an invitation on a Monday and some on …
Generalization of Classic Question Order Effects Across Cultures
Questionnaire design is routinely guided by classic experiments on question form, wording, and context conducted decades ago. This article explores whether two question order effects (one due to the norm of evenhandedness and the other due to subtraction or perceptual contrast) appear in surveys of probability samples in the United States and 11 other countries (Canada, Denmark, Germany, Iceland, Japan, the Netherlands, Norway, Portugal, Sweden, …
Applying Prospect Theory to Participation in a Capi/Web Panel Survey
Prospect theory states that the influential power of avoiding negative outcomes is stronger than that of achieving positive outcomes. In a survey context, this theory has been tested with respect to not only participation in a CATI survey, but also giving consent to data linkage in CATI surveys. No study, however, has tested the theory with respect to participation in a CAPI or web survey. This study does so in a mixed-mode panel context; it also…
The Role of E-mail Communications in Determining Response Rates and Mode of Participation in a Mixed-mode Design
This article is concerned with the extent to which the propensity to participate in a web face-to-face sequential mixed-mode survey is influenced by the ability to communicate with sample members by e-mail in addition to mail. Researchers may be able to collect e-mail addresses for sample members and to use them subsequently to send survey invitations and reminders. However, there is little evidence regarding the value of doing so. This makes it …
Place, Personal Characteristics and Councillor Roles
The government proposals on the structure and internal management of local government put forward in 1991 raise important questions for the representative and decision-making roles of councillors. A re-analysis of data collected for the Widdicombe committee in 1985 was conducted, using multiple regression. The findings suggest that the time councillors spend on different council activities is significantly affected by a number of locality variabl…
The British Crime Survey Sample
In this journal, Elliott and Ellingworth (1997)reported their attempts to assess the impact of certain sources of survey error on the British Crime Survey. This article attempts to correct some flaws in their article, to place their results in a wider context, and to provide some further - arguably more robust - estimates of the impact of non-response bias
Developing quality standards for cross-national survey research
This paper addresses methods for the development of quality standards for cross-national quantitative surveys. Five conceptual approaches to the development of standards are presented and the properties and consequences of each are discussed. The aim is to provide researchers with a rational set of arguments for choosing a particular approach in a given situation. The development of quality standards is particularly complicated in the case of cro…
Measuring Change in Employment Characteristics
We have demonstrated that the use of PDI results in lower levels of observed change in each of a number of characteristics of the respondent's employment. The reduction in observed change is particularly pronounced for SOC, SIC, and the number of employees at the respondent's workplace. This reduction in observed change appears to represent a reduction in measurement error as the effect of PDI is particularly pronounced amongst respondents who ha…
The Feasibility of linking household survey and administrative record data
Linkage of household survey responses with administrative data is increasingly on the agenda. Unique individual identifiers have clear benefits for making linkages but are also subject to problems of survey item non-response and measurement error. Our experimental study that linked survey responses to UK government agency records on benefits and tax credits elucidates this trade-off. We compare five linkage criteria: one based on a respon-dent-su…
The International Conference on Methodology of Longitudinal Surveys (Mols), 12-14 July 2006
La conférence internationale sur la méthodologie des enquêtes longitudinales : Du 12 au 14 juillet 2006, à l'université d'Essex, Peter Lynn, avec le « UK Longitudinal Studies Centre » et l'« International Association of Survey Statisticians » (IASS), a organisé la conférence internationale sur la « Methodology of Longitudinal Surveys » (MOLS 2006). Le BMS a rassemblé des matériaux des sites Web de MOLS 2006 et de l'« International Statistical Ins…
Methodology of Longitudinal Surveys
In this chapter, our focus is on panel conditioning with respect to attitude questions. Our methodological approach is different from the majority of previous studies in this area, in that we do not attempt to estimate biases in marginal and associational distributions through comparison with a fresh cross-sectional sample. Rather, our approach is based on testing hypotheses on a single dataset, derived from an explicit theoretical model of the p…
It Is Time Computers Do Clever Things
Despite the increased interest in assessing the effects of dependent interviewing (DI) on data quality, the impact of DI on interviewer burden and interviewer-respondent interaction remains currently unexplored and undocumented. Drawing on Japec's work, this article attempts to evaluate the impact of DI on interviewer burden and describes the mechanisms by which DI affects perceived interviewer burden and ultimately data quality. We use a diverse…
Extended Field Efforts to Reduce the Risk of Non-response Bias
We examine the effects on survey estimates of extended interviewer efforts to gain survey response, including refusal conversion attempts and attempts to make contact with difficult-to-contact sample members. Previous research on this topic has identified that extended efforts do appear to affect estimates, and in ways that seem consistent with bias reduction. We extend the previous research in three ways. First, we provide the first study of cha…
The Impact of Mobile Phones on Survey Measurement Error
We propose a framework of ways in which the different context of mobile interviews-such as multi-tasking, distraction, and the presence of others-and differences inherent in the technology can influence survey responses. The framework also highlights the mechanisms through which these influences operate. We evaluate selected elements of the framework using data from a randomized experiment in which respondents were interviewed by mobile or landli…
Improving Survey Methods
Invited talks were given by Jelke Bethlehem (Statistics Netherlands), Don Dillman (Washington State University), and Peter Lynn (University of Essex). The second conference entitled “Advancing Survey Methods” was held two years later in
Longer Interviews May Not Affect Subsequent Survey Participation Propensity
Survey researchers often assume that respondent burden is an important determinant of survey participation propensity and that interview length is a good indicator of burden. However, there is surprisingly little evidence of the effect of length of a completed interview on subsequent participation propensity, particularly in the case of face-to face surveys. This article presents results from a large-scale randomized experiment in which responden…
The Problem of Nonresponse
Many books about survey sampling tell you how the precision of survey estimates depend on the sample design. However, this assumes that data are obtained for every unit in the selected sample. This is rarely the case; most surveys experience some nonresponse. This can affect the survey estimates. This chapter aims to explain how and why nonresponse occurs, why it is important, and what can be done to minimize any undesirable consequences, either …
Methods for Probability-Based Online and Mixed-Mode Panels
This special issue is devoted to discussion of probability-based survey panels that collect data either solely or partly through online questionnaires. Panels of this kind have been around for a long time, though they have been few in number, but recent years have seen several new panels start up in Europe. This has led to renewed interest in the methodology of such panels and also to deeper questioning of the role of these panels. On one hand, t…
Using Motivational Statements in Web-Instrument Design to Reduce Item-Missing Rates in a Mixed-Mode Context
Journal Article Using Motivational Statements in Web-Instrument Design to Reduce Item-Missing Rates in a Mixed-Mode Context Get access Tarek Al Baghal, Tarek Al Baghal * *Address correspondence to Tarek Al Baghal, ISER, University of Essex, Wivenhoe Park, Colchester, Essex UK CO4 3SQ; e-mail: [email protected]. Search for other works by this author on: Oxford Academic Google Scholar Peter Lynn Peter Lynn Tarek Al Baghal is a senior research offi…
Targeted Appeals for Participation in Letters to Panel Survey Members
Previous research into survey invitation letters and prenotification letters has sought to identify optimal features of a standard letter that can be sent to all sample members. In the spirit of adaptive design, this study seeks to establish whether it can be advantageous to target different versions of a letter to different sample subgroups. Specifically, a paragraph intended to heighten perceptions of relevance of the survey is varied among six…
The Role of E-mail Communications in Determining Response Rates and Mode of Participation in a Mixed-mode Design
This article is concerned with the extent to which the propensity to participate in a web face-to-face sequential mixed-mode survey is influenced by the ability to communicate with sample members by e-mail in addition to mail. Researchers may be able to collect e-mail addresses for sample members and to use them subsequently to send survey invitations and reminders. However, there is little evidence regarding the value of doing so. This makes it …
Design and implementation of a high-quality probability sample of immigrants and ethnic minorities
Surveys of immigrants face challenges of coverage, representativeness, and response rates. Longitudinal studies of immigrants and ethnic minorities, which have potential to address pressing issues in demographic research, are rare or partial. In the absenc
Item Nonresponse Rates and Panel Conditioning in a Longitudinal Survey among Youth
The article examines two important aspects of data quality in self-completion surveys of young people, taking advantage of a unique data source: Understanding Society: the United Kingdom Household Longitudinal Study. Young persons aged 10–15 are asked to complete a self-administered paper questionnaire at annual intervals. The number of completed interviews varies over waves from 4,049 to 5,020. Data are also collected from parents, providing imp…
Applying Prospect Theory to Participation in a Capi/Web Panel Survey
Prospect theory states that the influential power of avoiding negative outcomes is stronger than that of achieving positive outcomes. In a survey context, this theory has been tested with respect to not only participation in a CATI survey, but also giving consent to data linkage in CATI surveys. No study, however, has tested the theory with respect to participation in a CAPI or web survey. This study does so in a mixed-mode panel context; it also…
Generalization of Classic Question Order Effects Across Cultures
Questionnaire design is routinely guided by classic experiments on question form, wording, and context conducted decades ago. This article explores whether two question order effects (one due to the norm of evenhandedness and the other due to subtraction or perceptual contrast) appear in surveys of probability samples in the United States and 11 other countries (Canada, Denmark, Germany, Iceland, Japan, the Netherlands, Norway, Portugal, Sweden, …
Advances in Longitudinal Survey Methodology
Text Messages to Incentivise Response in a Web-First Sequential Mixed-Mode Survey
This article reports research exploring the benefits of adding text messages to the contact strategy in the context of a sequential mixed-mode design where telephone interviewer administration follows a web phase. In a web-first mixed-mode survey, supplementing the contact strategy with text messages can help increase the response rate at the web phase and, consequently, reduce fieldwork efforts at the interviewer-administered phase. We present r…
The Impact of day of Mailing on Web Survey Response Rate and Response Speed
The day of the week on which sample members are invited to participate in a web survey might influence propensity to respond, or to respond promptly (within two days from the invitation). This effect could differ between sample members with different characteristics. We explore such effects using a large-scale experiment implemented on the Understanding Society Innovation Panel, in which some people received an invitation on a Monday and some on …
Benefits of increasing the value of respondent incentives during the course of a longitudinal mixed-mode survey
This paper explores the effects of increasing the value of survey incentives on response rates and fieldwork efforts using data from a large-scale randomised experiment embedded in wave 12 of a national probability-based longitudinal survey. We also investigate whether effects differ between previous-wave respondents, who were sent an unconditional incentive, and previous wave non-respondents, who were offered a conditional incentive. The treatme…
Survey Methodology and Nonresponse (20 works) · Psychology (16 works) · Computer Science (14 works) · Political science (13 works) · Sociology (12 works) · Geography (10 works) · Statistics (10 works) · Economics (9 works) · Mathematics (8 works) · Survey data collection (8 works)