Evaluating the relationship between citizens' motivation and the quality of Volunteered Geographic Information: A case study of urban green spaces in district 6 of Tehran

ABSTRACT
Recent years have witnessed a tremendous increase in Volunteered Geographic Information, virtually any sort of geographic information or knowledge assembled through non-professional volunteers participating in different projects. VGI has received great attention owing to modern advancements suchlike the Web 2.0, the Internet, and various location-aware mobile devices. The accuracy and quality of such information are, for the most part, influenced by the personal interests, motivations, and characteristics of those participating, which in today’s world translates into a major tool for serving the needs of decision-makers and planners and of course governments and thereby a topic worthy of scrutiny. In this light, the present study proceeds with the design of a VGI system intended to map green spaces in District 6 of Tehran concerning the motivations and characteristics of contributors and their effects on the final quality of information produced. As per the results, the following motivations were identified as most effective on the quality of visualized geographic green areas: the practicality of project objectives, sense of altruism, and familiarity with the region with corresponding regression coefficients of 0.31, 0.35, and 0.59, respectively. Moreover, information gathered from contributors aged 35 or above with educational qualifications of master’s degrees was highest in terms of quality.
Extended Abstract
Introduction
Volunteered Geographic Information (VGI) is understood as a means for the production, collection, and propagation of geographical data acquired voluntarily from non-professional individuals. Within this framework, citizens are analogous to artificial sensors capable of assimilating their five senses to consciously interpret and gather information from their surroundings. In addition to naturally-oriented sensory inputs acquired through citizens, synthetic (artificial) sensors including mobile devices, cameras, and other GPS-based systems with internet access, can also be employed to increase public participation in processes of production, sharing, and use of spatial data. Despite the merits of free access to valuable information, given the user-driven origins of such data, VGI is undoubtedly subject to certain uncertainties and inaccuracies that make it impractical on a more general scale. Seeing as to how different participants are predisposed to different levels of knowledge, experience, literacy, motivation, and distinct interpretations of their surroundings, it is highly likely that any information gathered from such individuals would surely comprise various heterogeneities and errors, with low spatial accuracy which refers to the spatial difference between regions nominated by citizens and actual data acquired through field surveys. Goodchild (2007) describes VGI as a significant source of information, primarily conditioned toward motivation. Herein, certain inquiries arise: how can an uncoordinated crowd of individuals produce a mesh of data without any financial incentives or the official organization to coordinate the process? What are the incentives therein? What organizational guidelines govern such cases? This hints at the significant relationship between an individual’s motivations for participation and the quality of spatial data produced.
 
Methodology
This study proceeds with an initial design and development of a web-based VGI system for gathering biographical and geographical information about citizens, followed by an evaluation of the gathered geographic data using specific indicators. Finally, the effects of participants’ characteristics and motivations on the quality of generated geographical data were calculated using spatial indicators and statistical analysis.
The system’s primary web page includes options for registering: biographical information, motivation questionnaire items, and geographical locations. The biographical information listing comprises items of age and education, which after registration opens access to the questionnaire for evaluating citizen motivations for enrolling in the system (The practicality of the VGI project objectives, Sense of altruism, The increasing personal level of knowledge, Promoting social interactions, and Familiarizing oneself with the study area). Following the completion of the questionnaire, users are granted access to delineating, editing, and removing geographical locations in the system. The registered information is then used for further analysis.
VGI quality was assessed in this study using three spatial indicators for evaluating the accuracy of polygons drawn by citizens in terms of shape and location. The area and perimeter difference indicators measure the difference in values of area and perimeter between polygons drawn by citizens and reference data (actual borders). The central distance indicator quantifies the degree of dislocation or spatial deviation between drawn polygons and reference dataStatistical analysis of the acquired data from the system, including biographical information, motivation questionnaire, and drawn polygons of locations was conducted using SPSS to investigate and evaluate the correlations therein. As a final step, regression analysis was applied alongside insights from motivation questionnaires to evaluate the relation between participants’’ motivations and the quality of drawn polygons.
 
Results and discussion
A total of 127 citizens registered as users in the proposed system and proceeded with filling out the questionnaire items and drawing polygons of specific locations (three parks including Shafaq, Doostan, and Sa’ai). most of the users (43) were aged 31 to 35 years old. 78.7% of individuals participating in this study showed proof of university degrees. Among the mentioned motivations, altruism appeared most frequently in the high and very high impact categories (82.6%), followed by familiarity with the region (59.8), and learning and promotion of knowledge (42.5%). Variance analysis tests were applied to assess the difference between different categories of user profiles (age and education) in terms of the quality of drawn polygons (derivatives of data quality indices) and The least significant difference test was also used to compare average polygons quality for all 4 categories of age and education. With the presumption of a normal distribution and constant variance, the only significant factor causing the difference between categories is conceivably the average value. Thus, considering values obtained for F at the 95% confidence interval, the null hypothesis of equal average quality for polygons drawn by users from different age groups and educational backgrounds is rejected at the 95% confidence interval, indicating significant changes in the quality of drawn polygons among different age groups and educational levels. Results show the highest quality of drawings with significantly higher values occurred for the 35 or above age group and master’s education
the results of the regression analysis showed the higher relevance and significance of VGI objectives to individual tastes and greater inclinations of altruism and familiarity with the region, the higher the quality of drawn polygons.
 
Conclusion
Participation in VGI projects takes place among different social groups, each of which has its specific motivations and characteristics that influence the accuracy and quality of generated data. With this background, the present study sought to design and develop a web-based VGI system to assess the relationship between biographical characteristics (age and education) and participants’ motivations and their effects on the quality of generated data. Statistical analysis was used to measure the mentioned impacts, with results pointing to “altruism” and notions of “helping fellow citizens” along with factors of age and education as highly effective in increasing the quality of data all the while improving user experience and skill.
 
Funding
There is no funding support.
 
Authors’ Contribution
The authors contributed equally to the conceptualization and writing of the article. All of the authors approved the content of the manuscript and agreed on all aspects of the work declaration of competing interest none.
 
Conflict of Interest
The authors declared no conflict of interest.
 
Acknowledgments
We are grateful to all the scientific consultants of this paper.