A total of 196 valid responses to the questionnaires were received (Fig. 1). The current jobs of the participants were diverse, and most responses came from Brazil because this was where the questionnaire could be sent to people and institutions known by the authors.
The responses were divided into a group of “professionals” with 79 people and a group of “academics” with 118 people. The purpose of this division was to identify the specific characteristics of academic behavior through a comparative analysis between the groups.
A limitation of this approach is that most academics were Brazilian (79.7%), which could have biased the results, creating a regional scenario. For instance, there is specific software for the transformation of coordinates between reference systems that are only suitable for Brazil, and thus, some responses could have been inflated.
However, the “other” response option in all questions may have mitigated this problem by allowing people from other countries to provide responses indicating different software that is more suitable for their locality.
In addition, ASDIs are relatively little used in Brazil [3], and research funding institutions in the country do not make specific recommendations on the need to publish geospatial information or algorithms.
Practices of use
The group of professionals presented a higher frequency of use of geospatial algorithms (Fig. 2). The subsets of software more used among the group of professionals were computer aided design (CAD) and database management systems. However, academics were found to use geodesy and digital image processing (DPI) software more often.
Both groups presented a diverse set of uses of geospatial algorithms (Fig. 3). These categories were listed from common functions used in GIS, although their subdivision may have influenced the respondents. In addition, there were low use and knowledge of web processing service (WPS) in both subsets.
The results indicate a low adoption of WPSs in day-to-day activities and that functions regarding vector data and the conversion and transformation of coordinates/reference systems should be prioritized for the broad use of an SDI. However, in an ASDI, more functions regarding geodesy and DPI software should be implemented.
Practices of development
A higher development rate was found in the professionals group (Fig. 4); this group also showed a greater use of programming languages, web map building tools and development environments. Both academics and professionals indicated high rates of Python and Structured Query Language (SQL) use as languages used in their professional activities (Fig. 5). A greater use of Freemat/Matlab as development environments was observed for academics (Fig. 6).
The differences in the frequencies of development could be due to the different type of work performed by people inside academia, where there are broad areas of study, that do not necessarily require the development of algorithms. In a company, it might be more common to use algorithms to optimize processes for better production, avoiding wasting time and, hence, increasing profit.
These results show that Python and SQL should be present in an SDI implementation, so alternatives such as the Python Web Processing Service (PyWPS) could be considered. However, the use of SQL may have been inflated because most respondents considered queries to databases as algorithms, which, in a pragmatic view, could be considered just a necessary step for using a database. On the other hand, in an ASDI, the Freemat/Matlab environment should be enabled for processing through the web.
Practices of storage and sharing
The responses for this set of questions showed that the main place where algorithms are stored is in local file systems. Additionally, there is a higher sharing rate by professionals, and this groups shows more sharing of third-party algorithms (Fig. 7). There were few mentions of WPS as a method of sharing, and for professionals, there is a high use of repositories, while academics often use shared folders and email as a methods for sharing.
The differences between the two groups might be explained by the previously verified low use and development rates of algorithms by academics, who thus have fewer algorithms to share. However, the increase in sharing of third-party code could be due a higher number of algorithms now in people’s possession.
In addition, when comparing the percentage of people who always share algorithms (i.e., share to everyone through webpages), in the case of third-party code, there is a decrease in sharing. This finding could be related to the insecurity about algorithm licensing use, which reinforces the necessity of metadata in published resources.
Difficulties regarding finding, using and sharing algorithms
The responses to this set of questions showed that people still have some difficulties in finding the algorithms needed for their work (Fig. 8) because more than half of participants succeeded only sometimes (between 40% and 60% of times) in their search for algorithms. The main places where these searches occur are internet pages and plugin repositories, showing that WPSs and companies/institutions are unusual places for this task (Fig. 9).
The main barrier to the use of third-party algorithms identified by the participants was that codes are not adaptable to other fields of study. Furthermore, for the question regarding the difficulties of sharing, the most cited difficult was the necessity of providing technical support to users, and when dealing with third-party code, the identified difficulties were related to a lack of information and the need to contact the code’s authors.
However, when dealing with self-produced algorithms, professionals and academics diverge on some points (Fig. 10). For academics, there is a high need to be cited, while for professionals, this need is small, but there is a greater need to generate profit with the code.
In addition, there are fewer academics claiming any difficulty when sharing, and this could be explained by the fact that there are fewer algorithms in their possession and thus a lower number of people who see problems in sharing is natural.
In an ASDI context, tools related to citing authors should be included, and in a general SDI context, some ways to provide technical support and allow the contacting of authors should be identified.
User views of sharing platforms
This set of questions returned similar results for both groups. From the perspective of the users, the more important functionalities provided by a specific platform for sharing algorithms are download, upload, purpose description and algorithm search (Fig. 11). Furthermore, for people both inside and outside academia, a platform wherein the authors can publish their own code in a decentralized system is the ideal scenario.
Software description ranked higher than hardware description. This result could be because advances in hardware have solved the main necessities required by algorithms (storage capacity, velocity and memory). Hence, users do not have the same level of concern for this factor as for software requirements.