Abstract
The aim of this study is to investigate the effect of socio-economic inequality on students' academic success with the mediating role of cultural capital. This is a descriptive-survey and applicable research and in terms of the relationships between variables, it is a correlational type. To achieve this goal, the statistical population consisting of students at Tarbiat Modares University and a sample of 217 people were studied by a stratified random method. Data collection was carried by using questionnaires whose validity was confirmed by experts and their reliability by Cronbach's alpha coefficient. SmartPLS3 statistical software was used to analyze the data and test the hypotheses. The findings of this study show that socio-economic inequality and cultural capital of students have a positive and significant effect on their academic success, and socio-economic inequality also has an effect on students' academic success with the mediating role of cultural capital. The results of the study indicate that cultural capital can play a reinforcing role in reducing the negative effects of socio-economic inequality, and it is essential to pay attention to it in educational policy-making, promoting educational justice, and reducing social gaps. Also, strengthening students' cultural capabilities is a sustainable solution to improve academic success in conditions of inequality.
Introduction
In the present era, higher education, as an engine driving economic, social, and cultural development, plays a decisive role in the formation of human capital and improving the competitiveness of countries. Student academic success, one of the key indicators for evaluating the performance of educational systems, not only reflects the quality of educational and training processes of universities, but also predicts the capacity for innovation, entrepreneurship, and effective participation in national and international arenas (Talebi Khansari, 2021). The acceleration of technological and economic changes, along with the diversity of specialized needs, has made paying attention to the factors affecting academic success more of a focus for policymakers, academic planners, and researchers in the field of higher education (Osman et al., 2021). One of the most important of these factors is socio-economic inequality, which is rooted in differences in household income, parental education level, employment status, location, and access to cultural and educational facilities. These inequalities affect students' educational progress by creating opportunity gaps. Students from lower socioeconomic classes face more structural limitations in accessing academic resources, educational technology equipment, remedial classes, and academic communication networks; and these limitations directly reduce their learning capacity and educational competitiveness (Bozkurt et al., 2021). Pierre Bourdieu's theory of cultural reproduction provides a comprehensive framework for explaining how these inequalities are transmitted and perpetuated. According to this theory, in addition to economic capital, cultural capital; which includes a set of skills, knowledge, customs, attitudes, and access to intellectual and artistic resources, plays an important role in academic success. Cultural capital manifests itself in three forms: embodied (mental and physical habits and skills), objectified (cultural assets such as books, artworks, and educational tools), and institutionalized (scientific degrees and certificates) and increases the ability to effectively utilize educational opportunities (Blideh et al., 2014). The importance of cultural capital is that it not only acts as an independent source of influence on academic success, but also can play a mediating role in the relationship between socio-economic status and academic performance. In other words, the level and quality of students' cultural capital can determine the intensity or weakness of the effects of socio-economic inequality on academic success. Based on the available evidence, even students who are economically disadvantaged can compensate for educational gaps and benefit more from available academic opportunities by having rich cultural capital (Bodat et al., 2017; Radulović et al., 2020). Therefore, the present study aimed to investigate the impact of socio-economic inequality on students’ academic success and analyze the mediating role of cultural capital in order to provide the necessary scientific evidence for the development of intervention programs and educational policies. Finally, the main question that this study seeks to answer is as follows: Can cultural capital play an effective mediating role in the relationship between socio-economic inequality and students’ academic success?
Theoretical foundations
Socio-economic inequality
Socio-economic inequality, as one of the most important structural issues in contemporary societies, refers to persistent differences in income levels, job status, education, and opportunities to access social and cultural resources. This inequality is often rooted in social history, economic structure, and resource distribution policies, and is usually transmitted from one generation to another. In capitalist societies, these inequalities are entrenched in the form of social classes, and individuals belonging to lower classes face greater obstacles to growth and advancement (Bozkurt et al, 2021). Edward Weber, a classical sociologist, considered socio-economic inequality to be the result of the interaction of the three factors of "social status", "power", and "economic class" and emphasized that education is one of the main arenas for the reproduction of these structures. According to this perspective, students who come from families with low socioeconomic status not only lack financial resources but also have a limited network of contacts that reduces their academic and career opportunities (Kosyakova, Bills, 2021).
 Cultural Capital
From Bourdieu's perspective, cultural capital is a set of symbolic and immaterial resources that an individual acquires in interaction with the family and social environment and through which he improves his educational and social positions. This capital appears in the individual's behavior, attitude, skills, and ability to understand and utilize cultural and scientific products. One of the important aspects of cultural capital is its role in enabling the individual to make optimal use of educational opportunities; so that an individual with a high level of cultural capital, even in limited economic conditions, can have significant scientific performance (Spink, Hubbard, 2021). Cultural capital has three main forms: embodied, objectified, and institutionalized. The embodied form includes language skills, learning styles, cultural awareness, and intellectual tendencies that are transmitted to the individual through everyday interaction in the family and society. The objectified form is manifested in the form of cultural assets such as books, educational tools, works of art, and access to scientific media. The institutionalized form of cultural capital refers to scientific and professional certificates and diplomas that are officially awarded by educational institutions and have value in the labor market and society (Boros et al., 2021).
 Academic success
Academic success is a multidimensional concept that goes beyond grades and GPA, to the quality of academic participation, research abilities, and the extent to which learning opportunities are utilized. This success refers to the extent to which an individual achieves the educational goals set by the educational system and is the result of a combination of individual, social, and environmental factors (Almeida et al., 2021). Motivational theories such as self-determination theory emphasize the role of intrinsic motivation and learner autonomy; while social learning theory emphasizes the interactions between the individual and the educational environment. The combination of these perspectives shows that academic success cannot be examined in isolation from an individual’s social and cultural context (Osman et al., 2021).
he relationship between concepts and the mediating role of cultural capital
The relationship between socio-economic inequality, cultural capital, and academic success is a dynamic and multi-path relationship that can be examined in the form of mediation models. Families with high socio-economic status usually provide more resources to create and strengthen their children’s cultural capital, such as enrolling in art and science classes, cultural trips, access to libraries, and the use of new learning technologies. This cultural capital then affects academic success, as students with high cultural capital have broader access to knowledge and scientific networks and adjust their educational orientation based on long-term goals (Bozkurt et al., 2021).
Research Method
This research is applicable in terms of purpose and descriptive-survey in terms of research implementation method. The statistical population of the study consists of sociology students at Tarbiat Modares University of Tehran. Considering the number of these students, a sample of 217 people was selected from them by stratified random method, among whom the research questionnaire was distributed. The research data collection tools were Bourdieu's Cultural Capital Questionnaire, Wells's Academic Achievement Questionnaire (2010), and the researcher-made socio-economic inequality questionnaire. In this study, structural equation modeling using the partial least squares and PLS software was used to test the hypotheses and verify the model. PLS is a variance-based approach that requires fewer conditions compared to similar structural equation techniques such as LISREL and EMON, and its main advantage is that it requires fewer samples compared to LISREL modeling.
 Research findings
Based on the results of the first hypothesis, that socio-economic inequality affects students' academic success, with a standardized path coefficient of 0.309 and a t-statistic of 3.60, it indicates the existence of a positive and significant relationship. The significance level of 0.000 fully supports the rejection of the null hypothesis and the acceptance of the research hypothesis. In other words, as the level of socio-economic inequality increases, significant changes are observed in students' academic success. This relationship indicates that unbalanced socio-economic conditions can affect the path of university education progress; of course, the positive direction of the coefficient indicates that in the sample under study, socio-economic differences, along with other interrelated factors, had a direct relationship with the level of academic success, which could be due to the simultaneous effect of mediating variables such as cultural capital.
The second hypothesis, which states that cultural capital has an effect on students' academic success, has shown the highest intensity of the direct effect among the hypotheses, with a standardized path coefficient of 0.504 and a t-statistic of 7.03. The significance level of 0.000 confirms that cultural capital has a very strong role in improving academic performance. This finding, in line with Bourdieu's theory and previous studies, shows that the skills, knowledge, attitudes, and cultural tools that students possess directly affect the quality of learning, their ability to participate in science, their academic self-confidence, and their intrinsic motivation; and can even compensate for the limitations caused by unfavorable economic conditions to a large extent. The third hypothesis, which states that socio-economic inequality has an effect on students' academic success through the mediation of cultural capital, with a standardized path coefficient of 0.485 and a t-statistic of 5.13, indicates the existence of a strong and significant indirect effect. The significance level of 0.000 rejects the null hypothesis and indicates that cultural capital has been able to moderate and mediate the relationship between socio-economic inequality and academic success. This means that in conditions of inequality, if students' cultural capital is richer, the negative effects of socio-economic constraints on academic success are reduced and can even lead to improved educational outcomes.
Discussion and Conclusion
The findings of the present study show that socio-economic inequality has a direct and negative effect on the academic success of students majoring in sociology at Tarbiat Modares University, while cultural capital has a positive and strong effect on academic success and, in addition, as a mediator, has been able to moderate a significant part of the negative effects of inequality. The high path coefficient of cultural capital (0.504) along with a significant t-statistic confirms the pivotal position of this variable in the educational structure of students, and its mediating role with a coefficient of 0.485 shows that even in limited socio-economic conditions, students with higher cultural capital are able to reduce educational gaps caused by inequality and improve their academic success. In explaining the results of the first hypothesis, it can be said that the path coefficient of 0.309 and the t-statistic of 3.60 reveal a positive and significant relationship between socio-economic inequality and academic success. This is in line with previous studies such as OECD (2018) and Bozkurt et al. (2021) that state that differences in income, parental education, and access to educational resources strongly affect learning opportunities, and students from lower socio-economic classes usually face serious limitations in accessing academic facilities and participating in academic activities.
In explaining the results of the second hypothesis, the intensity of the effect of cultural capital with a path coefficient of 0.504 and a significant t-statistic of 7.03 had the highest direct effect in the research model. This finding is consistent with the results of research by Akbarpour Zanglani et al. (2016) and Saei et al. (2015), which showed that family cultural capital promotes academic success by providing scientific and cultural resources, participating in educational environments, and strengthening scientific communication. Cultural capital is practically known as a factor that develops research skills, scientific self-confidence, and self-regulation ability, all of which are effective in improving students' academic performance.
In explaining the results of the third hypothesis, the path coefficient of 0.485 and a t-statistic of 5.13 confirmed the existence of a strong indirect effect, which, in accordance with the findings of Al Barazi (2021) and similar domestic research, cultural capital can moderate the intensity of the effect of socio-economic inequality on academic success. This compensatory role of cultural capital, from the perspective of Bourdieu's theory, refers to the ability to transform symbolic and cultural resources into social and academic success, and in the context of Iranian higher education, where there are clear differences between social classes in access to academic facilities, it becomes doubly important.