Bibliometric Analysis of Waqf Education on Google Scholar from 2019 to 2022 using VOSviewer

Bibliometric analysis using data on the number and authors of scientific publications as well as articles and citations in them aims to measure the outcomes of researchers, institutions, and countries, in order to identify national and international networks and map the development of new (multidisciplinary) fields of science and technology, this is also known as known as Scientometrics. While, VOSviewer is software for analyzing bibliometrics in order to find research novelties that have not yet appeared in the realm of science and knowledge. This study aims to analyze waqf education on Google Scholar from 2019 to 2022. This study aims to analyze the bibliometrics of waqf education on the Google Scholar data research. The research method used is using the publish and perish application to collect reference data for the last four years from 2019 to 2022. Then use the VOSviewer application to analyze the bibliometrics by


INTRODUCTION
Waqf and Education are two interrelated terms within the scope of Islamic Education filed, this is related to the main figure in waqf management, namely Nazir 1 .Nazir's profession should be in the same position as professionals such as legal experts, public accountants, bankers, or investors 2 .Therefore, a nazir waqf professional education program is needed, more specifically the curriculum for this program.
The question is, how much research related to waqf directly intersects with the area of educational research?To address this question, an analysis of curriculum development, competency qualification framework, and professional education programs can be used.
Regarding nazir issue, waqf management should be in the form of a charitable organization that is independent, professional, trustworthy and focused on productive waqf forms 3 , because there are many waqf management 4 and use of waqf income for the development of higher education 5 and also waqf in the health care system can increase social benefits for poor and needy patients 6 .Increasing Nazir competence in the development of productive waqf is not only to be knowledgeable in fiqh, but also has to be equipped with business management and entrepreneurship competencies, because it will develop and empower waqf assets to be more productive 7 .

LITERATURE REVIEW
In mapping publications in the fields of waqf and education, bibliometric data analysis has recently been conducted.This analysis is very interesting, because it can be clearly visualized and in line with current research developments.Visualizing the data is a mapping of existing forms of research.One of the mapping tools that can be used is VOSviewer which is software for mapping bibliometric data analysis.Several types of bibliometric mapping can be performed with VOSviewer including co-authorship maps, citation maps, co-citation maps, bibliographic coupling maps, and co-occurrence maps.
Bibliometric analysis using data on the number and authors of scientific publications as well as articles and citations in them aims to measure the outcomes of researchers, institutions, and countries, in order to identify national and international networks and map the development of new (multidisciplinary) fields of science and technology, this is also known as known as Scientometrics 8 .
It was found that many affiliations, countries/regions, and research communities that contributed to research on waqf and its affiliates of cooccurring analyzes of bibliographic information from articles were collected.Several studies on bibliometric analysis have been done in various fields and methodologies, including waqf research, such as A bibliometric Review of the Waqf literature 9 , Bibliometric assessment of scholarly publications on waqf or Islamic endowment 10 and Islamic Social Finance: A Bibliometric Analysis 11 .The study on bibliometric analysis is fundamental in detailing the theoretical literature and developing an integrated theoretical framework on quality of higher education 12 .This review provides reference points for entry into this interdisciplinary field 13 .However, from these previous studies, there has been no research that discusses bibliometric analysis with the mapping analysis method in educational research in the area of waqf for the last four years.The tool used is VOSviewer 14 to obtain information about the development and novelty of research 15 that has been conducted.Therefore, this research was designed for reviewing the development of research from the field of waqf education for the last four years (2019 to 2022) in the scope of Google Scholar data.

METHODS
The article data used in this study is based on research from publications that have been registered on Google Scholar Indexing 16 .The Google Scholar search database was used in this study because it can be accessed free of charge.
To collect research data, the Publish or Perish 17 reference manager tools were used 18 .Data collection was conducted in November 2022.The data were reviewed and selected according to the context relevant to the determination of keywords that matched the search for the themes needed in this research, then backed up into a file that would be retrieved through VOSviewer 19 .
Each article was checked for this research and articles related to education were selected.The keywords chosen are "Waqf" and "Education" for the Publish or Perish application and then filtered by title and abstract.As a result, 494 publications during the last four years for the 2019-2022 period with a total of 734 citations.
14 David Opeoluwa Oyewola and Emmanuel Gbenga Dada, "Exploring Machine Learning: A Scientometrics Approach Using Bibliometrix and VOSviewer," SN Applied Sciences 4, no. 5  (2022) The articles used in this study were published between 2019 and 2022.After that, the article is saved in *.ris format.Then, in the form of a bibliometric map, VOSviewer is used to visualize and analyze trends.filtered terms will be included in the VOSviewer network mapping visualization.The article data is mapped using the source database that has been generated.There are three forms of data mapping: network visualization, density, and overlay20 .

RESULT AND DISCUSSION
The growth curve for research on waqf education from 2019 to 2022 is shown in Figure 1.According to Figure 1, the number of publications published in educational research has increased from 79 to 110 in the last four years i.e., from 2019 to 2022.The year with the highest total was 145 in 2021.In 2020 and 2022 there were have a same number of 110 articles.

Figure 1. Level of Development on Waqf Educational Research
Mapping analysis was conducted to show the relationship between the terms contained in the educational research using waqf as a secondary keyword.Each connection is described in the network visualization.Several provisions are applied in the screening of terms in waqf education.The minimum number of occurrences of a term is 10 times.Thus, out of 2756 terms found, only 25 terms were used in visualizing publication data.
The visualization network shows the relationships between the displayed terms.The interrelationships between concepts are depicted in Figure 2. In network visualization, relationships are represented by networks or lines connecting terms.Clusters of terms in nazir waqf educational research are depicted in Figure 2.

Figure 2. Network Visualization of Waqf Educational Research
This study's network visualization is separated into several clusters (see Figure 3): (i) Cluster 1 has 7 items, the items are BWI, cash, cash waqf, money, waqf, waqf fund, and zakat.(ii) Cluster 2 has 7 items, the items are benefit, community, Islamic education, nazir waqf, productive waqf, strategy, waqf institution.(iii) Cluster 3 has 6 items, the items are accordance, field, implementation, land, mosque, waqf land.(iv) Cluster 4 has 3 items, the items are waqf nazir, waqf property, worship.(v) Cluster 5 has 3 items, the items are asset, manager, use.

Figure 3. Network Visualization of Waqf Term
From the network visualization data, it is known that waqf education is related to many terms.The term waqf is included in cluster 1 with a total of 25 links and a total strength of 363 links and occurs 252 times.Figure 3 shows several terms connected with the term waqf, namely Islamic education, waqf institution, waqf nazir, waqf property, worship, community, nazir waqf, strategy, productive waqf, benefit, manager, waqf fund, field, waqf land, zakat, cash, mosque, implementation, asset, BWI, money, and use.
As waqf is one of the learning contents within the scope of Islamic education, it is found that the connected terms of Islamic education as below:

Figure 4. Network Visualization of Islamic Education Term
The term Islamic Education is included in cluster 2 with a total of 12 links and a total strength of 27 links.Figure 4 shows several terms connected with the term waqf, namely waqf property, waqf institution, strategy, community, productive waqf, benefit, manager, waqf fund, waqf, cash waqf, dan asset.
As the third concept in waqf education, it is found the connected terms in the item nazir (Figure 5):

Figure 5. Network Visualization of Nazir Term
The term nazir is included in cluster 2 with a total of 10 links and a total strength of 28 links.Figure 5 shows some terms connected with the term nazir, namely waqf institution, waqf property, worship, strategy, productive waqf, waqf, waqf fund, waqf land, cash, cash waqf, and asset.

Figure 6. Overlay Visualization of Waqf Education Research
In an overlay visualization, the color of a node indicates certain properties of that node.For example, a node can represent a journal and the color of a node can indicate how many times the journal has been cited21 .
Figure 6 shows that the yellow or light color illustrates the novelty and the recent topics and terms used in waqf education research, namely: BWI, money, zakat, cash waqf, and Islamic education.While the blue or dark color indicates the publication of research articles is getting closer to the previous year to 2020, such as terms of waqf, land managers, mosques, assets, and cash waqf.

Figure 7. Density Visualization of Waqf Education Research
In this visualization, color indicates how the nodes are distributed in the underlying two-dimensional space of the visualization.Density visualization allows one to quickly identify dense areas where many nodes are located close to one another 22 .
The density of the number of studies is indicated by the brightness of the color and the relationship between one node and another.In the waqf education researches, it was found that there is an underlying two-dimensional space of the visualization in several terms, such as BWI, money and zakat.In addition, there is a very prominent color dimension, namely the terms waqf, cash waqf, asset and waqf institution.Table 2 shows the 10 highest terms connected to the waqf education term, namely waqf, cash waqf, asset, waqf fund, manager, waqf institution, strategy, waqf land, benefit, and waqf property.The highest correlation is found in the relationship between waqf education and waqf with a total link strength of 356.The relationship between waqf education and cash waqf with a total link strength of 114.The relationship between waqf education and asset with a total link strength of 96.The relationship between waqf education and waqf fund with a total link strength of 75.The relationship between waqf education and manager with a total link strength of 73.The relationship between waqf education and waqf institution with a total link strength of 65.The relationship between waqf education and strategy with a total link strength of 63.The relationship between waqf education and waqf land with a total link strength of 57.The relationship between waqf education and benefit with a total link strength of 52.The relationship between waqf education and waqf property with a total link strength of 42.From the figure 8 can be seen that publications with the term waqf show the highest level with 356 publications.However, there are not many articles that link the main actor in waqf, namely nazir as the manager who is responsible for the sustainability of waqf.Indeed, there is the term manager for 73 publications, but this is not solely associated with understanding the meaning of nazir, it could mean waqf managers who are not nazir or other people employed by nazir as managers, for example, articles

CONCLUSION
This study aims to analyze the bibliometrics of waqf education on the Google Scholar data research using Harzing's Publish or Perish and VOSviewer software for mapping analysis.The results show that there 494 publications during the last four years for the 2019-2022 period in the field of waqf education with a total of 734 citations.As for the number of interconnection relationships between terminologies in the existing research that the strongest number of relationships was term waqf of 356, cash waqf of 114, asset 96, waqf of fund 75, and manager of 73.While the frequently appeared was term waqf as much as 252 times, Cash waqf 71 times, asset 55 times, land waqf 41 times, and manager 36 times.The highest correlation is found in the relationship between waqf education and the term waqf.From the search results for Google Scholar data, no research has been found on Nazir's education, which is closely related to the topic of law and education.So, it is suggested to carry out further research related to the curriculum of the Nazir profession in the development of waqf.