Precursors and outcomes of satisfaction in business-to-business relationship marketing. Insights from Hawkers/street vendors leafy vegetable market in South Africa

Abstract The purpose of the empirical study was to determine the precursors and outcomes of customer satisfaction in the South African hawkers/vendors in the leafy vegetable market. Purposive sampling technique was used to collect data from 370 street vendors/hawkers using a self-administered questionnaire. Data were analysed using the structural model with the aid of SmartPLS 3. One of our findings reveals that word-of-mouth, commitment, trust, and customer loyalty are significantly influenced by customer satisfaction. This finding makes a major contribution to academic and practice because most literature, support the notion that trust and commitment are precursors of customer satisfaction. The results show that suppliers/farmers of leaf vegetables need to establish relationships that are focused on communication and product mix in order to satisfy customers in the leaf vegetable market. Our findings cement the argument that the relationship between the variables, i.e., trust, commitment, and satisfaction are interdependent and multifaceted. One can, therefore, conclude that the relationship between these constructs is dependent on characteristics of samples used for the study, industry sector and product type amongst other factors.


PUBLIC INTEREST STATEMENT
The unique selling proposition of this paper is to contribute to the variables necessary for the maintenance and development of relationship marketing within the leaf vegetable market in South Africa, given the much focused attention on the redistribution of land by the government as well as the fact that the agricultural sector plays a significant role in the economy of the country but there seems to be limited research on this sector.
The research was carried out in the Central Business District of Johannesburg among hawkers/street vendors who sell leaf vegetables. The research found that communication, product mix, satisfaction, commitment, trust, word-of-mouth and loyalty are important variables for the survival of farmers/suppliers of leaf vegetables.
The paper contributes significantly to the academic field, suppliers/farmers and policy formulation by coming up with recommendations and areas of future research.

Introduction
Literature on the relationship between marketing and customer satisfaction exists in different industries like banking (Rootman, Tait, & Sharp, 2011;Theron & Terblanche, 2010), manufacturing sectors (Mbango, 2015) and mainly on European samples (Mpinganjira, Bogaards, Svensson, and Mysen (2014). This suggests a lack of scientific research about the leafy vegetable markets in Africa. This study aims to determine factors that cause customer satisfaction and the outcomes of customer satisfaction in the leafy vegetable market in South Africa. The findings of this study have implications for theory and managerial decisions aimed at understanding customer satisfaction in the South African leafy vegetable market. Some researchers; Theron and Terblanche (2010); Deng, Lu, Wei, and Zhang (2010), Taleghani, Gilaninia, and Mousavian (2011); Morgan and Hunt (1994) and (Halimi, Chavosh, & Choshalyc, 2011) regard trust, commitment and communication as some reinforcements which have positive influence on customer satisfaction which also result in customer loyalty. On the contrary, studies by Mpinganjira et al. (2014) and Mbango (2017), regard these concepts as interlinked and therefore do not agree with the aforementioned. In this paper, the researchers argue that customer satisfaction is a precursor to commitment, trust, loyalty and word of mouth referrals. Mpinganjira, Bogaards, Svensson, Mysen, and Padin (2013) argue that commitment and trust are the key arbitrating factors which cause satisfaction; Mbango and Phiri (2015), Hau and Ngo (2012) also maintain that trust is the predicting factor leading to customer satisfaction.
Morden food services including the leafy vegetables market are facing conflicting challenges of high-quality demands from customers, safety guarantees as expected from government and increased profit expectations by owners (Ko, 2009). This indicates that factors like product quality as well as customer value play a significant role in the satisfaction of customers. In this study, trust, commitment and customer loyalty are positioned as the outcomes of customer satisfaction and product quality and customer value as predictors of customer satisfaction. In addition to the aforementioned constructs, product price, communication and product mix are regarded as the additional determinants of customer satisfaction in the leafy vegetable market in South Africa. Trust, commitment, customer loyalty and word of mouth are viewed as outcomes of customer satisfaction.
Hawkers/street vendors play a very critical role in the economy of South Africa. This market is regarded as the informal sector. According to Ligthelm (2006), informal sector businesses consist of informal businesses which are operated primarily in township areas, on kerb sides and at large transport interchanges. This is the market in which one can find the hawkers selling different consumer items including leafy vegetables. As outlined by Ligthelm (2006), a total of R51.7 billion was spent at informal businesses in 2004 and out of this amount, R10.4 billion (20.2%) of the spending was on hawkers'/street markets. Although this market is said to be informal, it plays a vital role in the economy of South Africa. Therefore, this calls for studies to be conducted in the leafy vegetable market as there exist limited studies in this area which deal with relationship marketing. Suppliers/farmers, more specifically business-to-business, are urged to manage their relationship with their customers by considering factors that affect their relationships in order to create more beneficial buyer-seller relationships and become more profitable (Morgan & Hunt, 1994).
Leafy vegetables are plant species of which the leafy parts, which may include young, succulent stems, flowers and very young fruit, are used as vegetables and specifically in South Africa more than 100 species of plants were identified as leafy vegetables (Jansen Van Rensburg et al., 2007).
Jansen Van Rensburg et al. (2007) further observe that for most species the young growth points and tender leaves are the plant parts that are used in the preparation of vegetable dishes. Many of the leafy vegetable species, especially those that grow as weed or in the wild are seasoned and highly perishable (Jansen Van Rensburg et al., 2007). Voster et al. (2002) observe that the role of leafy vegetables in the food consumption patterns of South African households is highly variable and depends on factors such as poverty status, degree of urbanisation, distance to fresh produce markets and time of the year.
2. Literature review, hypotheses development and research framework

Overview of studies on customer satisfaction
Customer satisfaction is regarded by secondary research (Han & Ryu, 2009;Spreng, Mackenzie & Olshavsky: 1996) as a central concept in the marketing field because it is crucial to meeting the needs and wants of customers. Many suppliers in business-to-business including the leafy vegetable market, deliver a product as well as customer satisfaction experience to customers, and they obtain the profits in return. Han and Ryu (2009) emphasize that customer satisfaction is an overall judgement process of the perceived difference between prior expectations and actual consumption.
Customer satisfaction refers to an individual's subjectively derived favourable evaluation of any outcome and experience associated with consuming a product (Maxham III, 2001). Garbarino and Johnson (1999) regard customer satisfaction as an overall evaluation based on the total purchase and consumption experience with a good or service over a period of time. Therefore, customer satisfaction is the key to customer retention and business success.
In the leafy vegetable market the farmer supplies the hawkers who resell the vegetables; the supplier's satisfaction with a relationship may be dependent on his own efforts invested into developing and maintaining the relationship, while his support and more involvement with the hawkers will make it easier for the relationship to yield satisfactory results (Svensson, Mysen, & Payan, 2010).

Research model and hypothesis development
Consistent with the literature, the current study proposes a research model ( Figure 1) which identifies product quality, customer value, product price, communication and product mix as direct predictors of customer satisfaction and word-of-mouth, commitment, trust and customer loyalty as outcomes of customer satisfaction in the South African leafy vegetable market. The precursors and the outcomes as well as the construction of the model are derived from literature and practical experience of the researchers. The following sections discuss the hypotheses in the proposed research model.

The relationship between product quality and customer satisfaction
Product quality is described as an overall judgement about the level of a supplier's performance (Nyadzayo & Khajehzadeh, 2016). According to Brink and Brendt (2004), the quality of service/ product highlights the ability of the supplier to determine correctly customer expectations and to deliver the product/service at a level that will at least meet those expectations. Customers of leafy vegetables more specifically in the business-to-business are unlikely to return or recommend a supplier/farmer that fails to meet their expectations of product quality. Anton, Camarero, and Carrero (2007) further confirm that customers' perception of a low level of quality in the products delivered will increase the customers' intentions to exit the relationship with the supplier. High product quality could motivate customers to strengthen the relationship with their supplier (Hess Jr, Ganesan & Klein, 2003).
In their studies, Pollack (2009), Dusuki and Abdullah (2007), Omotayo and Joachim (2008) concluded that product quality has a positive influence on customer satisfaction.
Product quality as Gounaris (2005) observe has traditionally been considered as a major prerequisite of achieving customer satisfaction. Han and Hyun (2015) indicate that quality is a main driver of satisfaction and further emphasize that the sustainability of a business' competitive advantage is reliant on its ability to provide products of high quality that ultimately leads to satisfied customers. Based on the above discussion, it is hypothesized that product quality of leafy vegetable has a positive influence on the customers' satisfaction: H1: Product quality has a positive influence on customer satisfaction.

The relationship between customer value and customer satisfaction
Customers (including the leafy vegetable hawkers) are increasingly demanding high-quality food products and superior customer service and more value for their money (Ryu, Han, & Kim, 2008). Suppliers/farmers of the leafy vegetables, therefore, need to put their focus on identifying prospects where they can offer superior value to their customers (Makhitha, Cant, & Theron, 2016). Customer value as defined by (Hellier, Geursen, Carr, & Rickard, 2003) is the customer's overall appraisal of the net worth of the service/product based on the customer's assessment of what is offered. Makhitha et al. (2016) and Flint, Blocker & Boutin jr. (2011) indicate that in order to offer value to customers, organizations must first determine what the customer needs are and whether the organization can provide it to them at a price the customer is willing to pay. This means that business-to-business suppliers should endeavour on matching their resources, abilities and competencies with customer needs so that they can serve them satisfactorily. Previous studies by Slater and Narver (2000); Lusch and Vargo (2014) further emphasize that managers must understand what their customers value in order to survive and prosper in competitive markets. When the customers' perceived value is successfully matched by the supplier, this will result in customers being satisfied. Customer value in the business-to-business environment can be created in the form of product and service or it can be through suppliers adapting to customers' changing needs or even suppliers cooperating to pursue mutual benefits (Flint, Blocker & Boutin jr. 2011). Previous studies (Lam, Shankar, & Murthy, 2004;Lampierre, Filiatrault & Chebat, 1999;Sirdeshmuki, Singh & Sabol, 2002;Spiteri & Dion, 2004) conclude that several measures of customer value are positively correlated with satisfaction. Given the above discussion, it is hypothesized that customer value in the leafy vegetable business-to-business markets has a positive influence on customer (hawker) satisfaction: H2: customer value has a positive influence on customer satisfaction.

The relationship between product price and customer satisfaction
Price is defined as what is given up or sacrificed to obtain a product (Han & Ryu, 2009). Price, as Han and Ryu (2009) observe, is often used as an indication in the customers'/hawkers' expectations of the product performance because customers tend to use price as a means of evaluating their experiences with a product and in the process shaping their attitude towards a provider/farmer. Customer perception of price fairness or unfairness significantly affects their overall satisfaction and behavioural intentions (Bolton & Lemon, 1999). (Ranaweera & Neely, 2003), Varki and Colgate (2001) further indicate that whereas product price perception is significantly associated with customer satisfaction, creating a positive product price perception may be a way of enhancing a firm's profit as well as customer's level of satisfaction. In support of this notion, Herrmann, Xia, Monroe, and Huber (2007) further indicate that product price perception influence customers' overall satisfaction judgements. Given the above discussion, it is hypothesized that the price of the leafy vegetable has a positive influence on the level of customers' satisfaction: H3: product price has a positive influence on customer satisfaction.

The relationship between communication and customer satisfaction
Communication is, as defined by Taleghani et al. (2011), the customer's perception of the extent to which a business interacts with its regular customers in a warm and personal way. The suppliers/ farmers of the leafy vegetables need to constantly be in touch with their customers (hawkers) in order to determine/identify their ever-changing needs and wants. Communication is the formal and informal exchanging and sharing of meaningful, timely and trustworthy information between buyers and sellers (Sin, Tse, Yau, Chow, Lee & Lau, 2005). For the purpose of this study, communication means the business-to-business suppliers keeping in touch with valued customers (hawkers), providing timely and trustworthy information on product and service changes, and communicating proactively if a delivery problem occurs. When there is effective communication between leafy vegetable suppliers and its customers, a better relationship will result and customers will become more satisfied (Halimi et al., 2011). Ndubisi and Wah (2005), Hau and Ngo (2012) conclude that an increase in the level of communication and customization of communication leads to an increase in customers' satisfaction, and the increase in relationship satisfaction. Given the above discussion, it is hypothesized that effective communication between the leafy vegetable suppliers and their customers will positively impact on customer satisfaction: H4: Communication has a positive influence on customer satisfaction.

The relationship between product mix and customer satisfaction
Product mix refers to a total number of products or product lines a supplier offers to his customers (Forza & Salvador, 2006). Wan, Evers, and Dresner (2012) state that is generally assumed that a firm can raise its overall market share by increasing its product selection, thereby, appealing to a larger and more diverse set of customers. According to Ramdas (2003), how firms choose to create variety in their product offerings, and how their supply chains are managed to implement variety, are key determinants of success of the supplier's strategy. Ramdas (2003) further observes that a supplier may create variety in anticipation of customer needs, offering consumers a choice from a set of ready-made offerings. In the leafy vegetable market, this refers to the suppliers/ farmers having/offering more than one type of product to the hawkers. The product types are fairly similar because they belong to similar product group of leafy vegetables although they are different. By offering a variety of leafy vegetables, a supplier will be in a position to offer a "onestop shop" for its customers.
H5: Product mix has a positive influence on customer satisfaction.

The relationship between customer satisfaction and word of mouth
With a wide range of products being introduced in the market as frequent as possible, consumers often find themselves sitting with the overload of information to process in order to make a product choice (Balasubramanian, Raghunathan, & Mahajan, 2005). As a result, customers tend to depend on other customers who used the product before to provide them with actual performance of the product (Gremler, Gwinner, & Brown, 2001). Word-of-mouth communication simply involves people sharing an assessment of their experiences, and positive word-of-mouth communication emerge from satisfactory service encounters (Kim, Nee Ng & Kim, 2009).
Customer satisfaction as Kim et al. (2009) observe is important to food service managers as well as leafy vegetable managers because it leads to repeat patronage, brand loyalty, and new customers through word-of-mouth promotion. Word-of-mouth recommendations from family, friends and colleagues who are satisfied with the supplier of leafy vegetables have a measurable impact on sales (Chen, Shi, & Dong, 2008). Babin, Lee, Kim, and Griffin (2005) further outline that when a service experience is particularly enjoyable and beneficial, consumers will be motivated to recommend their families and friends to that specific service provider. The same can be said about the leafy vegetable market whereby one hawker may recommend his/her leafy vegetable supplier to other hawkers.
According to Ulaga and Eggert (2006), customer satisfaction is widely accepted amongst researchers as a strong predictor of behavioural variables such as repurchase intention, word-ofmouth recommendation or even loyalty. This is supported by the study by Ranaweera and Prabhu (2003) which confirm that customer satisfaction has a strong positive association with customer retention and positive word-of-mouth endorsement. Kim et al. (2009) also found that higher customer satisfaction should increase return intention and provide word-of-mouth endorsements. Wangenheim and Bayon (2007) also emphasize that positive word-of-mouth is the outcome of high customer satisfaction ratings.
H6: Customer satisfaction has a positive influence on word of mouth referrals.

The relationship between customer satisfaction and commitment
According to Mpimganjira, Roberts-Lombard & Svensson (2017) commitment is a psychological sentiment of the mind through which an attitude concerning continuation of a relationship with a business partner is formed and there exists a desire to sustain a valued relationship from partners. Commitment is regarded as the explicit or implicit pledge of continuity between the customer and the supplier (Nyadzayo, 2010).
Customers are satisfied when they are in a relationship with their suppliers whereby there exist social interactions which facilitate problem-solving and resolving communication barriers (Chang, Wang, Chih, & Tsai, 2012). This will enhance the level of customer commitment to the relationship. Similarly, in the leafy vegetable market as Wali, Wrigh & Uduma (2015), observe commitment to the supplier as dependent on the customers' level of satisfaction. Mpimganjira, Roberts-Lombard and Svensson (2017) emphasize that satisfaction with the supplier influences the decision to maintain the relationship because the decision to commit to a relationship is influenced by the assessment of the efficiency of the past interaction. Chang et al. (2012) further outline that when satisfaction increases, relationship partners are less likely to exit the relationship as they are aware of the costs and risks inherent in terminating the relationship.
Given the above discussion, it is hypothesized that once customers are satisfied in a relationship, they are more likely to commit to such a relationship, therefore: H7: Customer satisfaction has a positive influence on commitment.

The relationship between customer satisfaction and trust
Trust is regarded as the belief that partner's promise is reliable and a party will fulfil his/her obligations in the relationship Han and Hyun (2015). Trust in leafy vegetable suppliers comes from customers' (hawker's) positive experiences that encourage them to continue with the relationship. Previous studies (Doney & Cannon, 1997;Morgan & Hunt, 1994;Rodriguez & Willson, 2002) view trust as a key mediating variable as it directly influences a commitment to a relationship. Gounaris (2005) view trust as a behavioural intention or behaviour that reflects a reliance on a supplier and that involves vulnerability and uncertainty, which means that before trust develops, some satisfaction guarantees should exist. Alluding to this notion is (Chen, Huang, & Sternquist, 2011;Leonidou, Talias, & Leonidou, 2008;Mpimganjira, Roberts-Lombard & Svensson, 2017) who emphasize that trust in business relationship takes time to build and can be difficult to build in the presence of unsatisfactory business exchange relationship.
Given the above discussion, it is hypothesized that satisfaction with the leafy vegetables supplied previously as well as services received will nurture trust amongst the relationship partners: H8: Customer satisfaction has a positive influence on trust.

The relationship between customer satisfaction and customer loyalty
Customer loyalty is the customer's willingness to make a commitment to repurchase products/ services of a specific supplier in order to strengthen a relationship with that supplier This will lead to the customer demonstrating the ability to specify a supplier as their provider of preference, resisting all opportunities of persuasion by competing suppliers (Yim, Tse, & Chan, 2008). Customer loyalty in the leafy vegetable market can be illustrated as the customer's assurance to a supplier or the customer's desire to keep an enduring relationship with the supplier (Zhang & Prybutok, 2005).
According to Han and Hyun (2015) customers who are satisfied with the supplier's products will demonstrate loyalty and recommend the supplier to other people. Other studies by Hu, Kandampully, and Juwaheer (2009) and Luo and Homburg (2007) regard customer satisfaction as an important ingredient of customer loyalty. Van Tonder and Roberts-Lombard (2015) observe that in consumer marketing there is consistent evidence that customer satisfaction contributes to repurchase intentions, behavioural intentions, customer retention and customer loyalty. The researchers in this study concur with the above notion and therefore hypothesize that customer satisfaction in the leafy vegetable market positively impact customer loyalty. Therefore, customer loyalty is seen as an outcome of customer satisfaction: H9: Customer satisfaction has a positive influence on customer loyalty.

Research design
Research design is regarded by Bryman and Bell (2015) as the roadmap that provides direction as to how the researcher intends to carry out the research. According to Cooper and Schindler (2014) it is the plan and structure of investigation to conceive as to obtain answers to research questions. Quantitative research approach and the survey method were used for in this study.

Population and sample
The respondents for the study included hawkers/street market vendors who sell the leafy vegetables to the public in Gauteng province of South Africa. The respondents consisted of hawkers/ street market vendors in the Gauteng province. A total of 400 questionnaires were distributed and 370 (93%) questionnaires were retained which were used as input into data analysis. The sample was deemed fit for the analysis using Roscoe (1975) calculator on sample sizes, which suggested that sample sizes ought to be more than 300 and less than 500 applicable for an utmost research.

Pre-testing of the instrument
The data collection instrument used for this study was a questionnaire. Questionnaires are a paper and pencil set of structured and focused questions (Van Zyl, 2014). A questionnaire was used for this study as it is cost-effective, practical and the data can be gathered within a short period of time. The original version of the research instrument was pre-tested with 20 participants, who were purposively sampled from the Central Business District of Johannesburg-all in the Gauteng Province. Each participant was presented with a copy of the questionnaire by the research assistants-who were trained towards the distribution and the collection of the questionnaires. Participants were asked to provide their opinion and comments on the clarity of the instructions; the wording of the questions; the layout of the questionnaire as well as the time taken in completing them. Corrections were then made-in line with the feedback received, which were factored into the final questionnaires towards the actual data collection.

Data collection procedure
Purposive sampling technique was used to collect the data from the respondents-who were the hawkers/street market vendors of leafy vegetables in the street pavements of the Central Business District of Johannesburg. Purposive sampling is a sampling technique whereby the respondents are chosen deliberately based on the qualities and information they possess. According to (Etikan, Musa, & Alkassim, 2015) when using the purposive sampling the researcher decides what needs to be known and sets out to find people who can and are willing to provide the information based on their knowledge or experience of the subject/concept. Purposive sampling was chosen in this study because the researchers wanted to understand the relationship between the constructs in the leafy vegetable market and therefore have purposively targeted the hawkers or street vendors. The collection lasted for a month before the required sample size was received. The participants were made to fulfil certain requirements before answering the questions. First, participants were supposed to be the hawkers or sellers of leafy vegetables irrespective of their gender, age or nationality. Secondly, they were to be selling the leafy vegetables in Gauteng Province. After that clarification, questionnaires were then distributed to the respondents by the research assistants at their stalls or selling points-which were all in the Gauteng province. The basis of the research work was first explained by the research assistants without any compulsion on participants' part to either accept to take part in the study or to ignore answering the questionnaires-after which questionnaires were handed to them to complete. Those who were willing to take part in the exercise but were not comfortable in filling the questionnaires on their own were assisted by the research assistant.

Measurement and questionnaire design
The research constructs were developed solely on already validated measures. All scale items were rearticulated to relate exactly to the context of the current study's requirement. A 7-point Likert scale was employed to measure the constructs ranging from "1-strongly disagree" to "7-strongly agree". All constructs used a seven-item scale which was adopted as follows: a quality which was adopted from Goffin, Lemke, and Szwejczewski (2006), Mbango (2015), and Suki (2016). Customer value and service quality were adopted from Nyadzayo and Khajehzadeh (2016); communication was adopted from Zineldin & Fonsson (2000); product price was adopted from Suki (2017); product mix which was own construction by the researchers, customer satisfaction and trust were adopted from Morgan and Hunt (1994), Svensson et al. (2010), Mpinganjira et al. (2014); customer loyalty was adopted from Suki (2016)) word of mouth was adopted from Baker, Donthu, and Kumar (2016) and lastly commitment which was adopted from Morgan and Hunt (1994), Svensson et al. (2010). In line with the recommendation by Nunnally (1978), a minimum of three items were used per construct so as to guarantee suitable reliability.
The questionnaire was divided into three parts; Part A contained the introduction of the questionnaire to the participants; Part B contained demographic profile with gender, age, citizenship as well as the duration the respondents have been in business while Part C contained questions about the variables that were used in the study-namely: quality, customer value, communication, product price, product mix, service quality, customer satisfaction, customer loyalty, word of mouth referrals, trust and commitment using a seven-point Likert scale which was anchored from "1-strongly disagree" to "7-strongly agree".

Descriptive statistics
Data analysis for the descriptive statistics of the sample was carried using the Statistical Package for Social Sciences version 25. The results of the analysis show that of the 370 vegetable vendors that participated in the study, 100 (27 per cent) were males and 270 (73%) were females. These results show that over two-thirds of the participants are females. The higher participation of females compared to males in the study could probably be attributed to the higher number of females in the informal economy. In terms of the age distribution of the study, the results show that the majority of the participants (49.2%) were in the age groups of 40-49 years. This is followed by those in the age bracket of 30-39 years comprising 25.9% of the participants. These results show that over 75 of the sample are between the ages of 30 and 49. The sample also consists of 28 (7.6 per cent) and 64 (17.3 per cent) in the age groups of 18-29 and 50 years and above, respectively.

Measurement model analysis
In analysing the measurement model, tests of convergent and discriminant validity were performed. The test of convergent validity examined the factor loading, composite reliability and average variance extracted (AVE). The final results of these analyses are presented in Table 1 and Figure 2. To achieve convergent validity, it is widely recommended that the factor loading should be significant and not less than 0.6, the composite reliability should be greater than 0.7 and the average variance extracted should be greater than 0.5 (Chin, Gopal, & Salisbury, 1997;Hair, Black, Babin, & Anderson, 2010). The results presented in Table 1 show that for all the constructs, the factor loadings are above 0.6. Moreover, the composite reliability estimates are above the recommended threshold of 0.7 and finally, the AVEs of the constructs are above 0.5. These results generally confirm the convergent validity of the measurement model. The Fornell-Larcker technique was used in assessing the discriminant validity (Fornell & Larcker, 1981). This technique states that discriminant validity is achieved if the square root of the AVEs is greater than the inter-factor correlations. The results of the discriminant validity analyses presented in Table 2 indicate that all the square root of the AVEs are greater than the correlations among the constructs, thus denoting that discriminant validity of the measurement is established.
Upon confirming the validity of the measurement model, the structural model was assessed to determine the significance of the hypotheses.

Structural model analysis
Prior to the analysis of the structural model, a collinearity test using the variance inflation factor (VIF) was performed to assess the level of collinearity threat among the independent variables. It is widely recommended a VIF value of less than 5 denotes that the collinearity among the independent variables is not of a major concern to the structural model analysis. The collinearity assessment for the current study indicates that the VIF values for the independent variables are between 1 and 1.507, thus indicating that the VIF values are lower than the critical recommended thresholds, hence collinearity does not present a threat to the analysis of the structural model.
The analysis of the structural model was also computed using the partial least squares structural equation modelling technique with the aid of Smart PLS 3. The results of the structural model analyses are presented in Figures 3 and 4 and Table 3. In Figure 3, the results of the structural model analysis with the path coefficients and the coefficients of determination (R 2 ) are presented. The results show that the significant determinants of vendors' satisfaction with the farmers/ suppliers explain 52.9% per cent of the variance in vendors' satisfaction with the farmers. It further shows that vendors' satisfaction with the farmers explains 13.4%, 36.4%, 32.2% and 26.4 of the variance in vendors' word-of-mouth marketing, commitment, trust and loyalty, respectively. To determine the path significance, a bootstrapping technique using 5000 re-samples were conducted. The results of these analyses are presented in Figure 3.  The results of the analyses show that product quality is not a significant (β = 0.041; p > 0.05) determinant of customer (vendors') satisfaction with the farmers; thus, H1 is not supported by the empirical evidence. Similarly, the result of the analysis suggests that customer value is not a significant (β = 0.056; p > 0.05) antecedent of vendors' satisfaction with the farmers. More so, product price is also not a significant (β = 0.021; p > 0.05) predictor of the vendors' satisfaction with farmers. Therefore, H2 and H3 are not supported. However, the results show that communication is significant and positively (β = 0.382; p < 0.001) associated with vendor satisfaction with farmers. Similarly, the results also suggest that the product mix is significant and positively (β = 0.389; p < 0.001) associated with vendor satisfaction with farmers. Therefore, the results of the analyses provide statistical support for H5 and H6.
In terms of the outcomes of customer satisfaction, the result of the analyses suggests that satisfaction with the vendor is significant and positively (β = 0.366; p < 0.001) associated with word-of-mouth marketing. This, therefore, provides empirical support for H7. The results further show that vendor satisfaction with farmers significantly and positively (β = 0.603; p < 0.001) predicts vendors' commitment to farmers. The results further show that vendors' trust in the farmer (β = 0.568; p < 0.001) and loyalty (β = 0.604; p < 0.001) to the farmer are both significantly and positively predicted by their satisfaction with the farmer. Hence, H7, H8 and H9 are empirically supported by the results of the analyses. A summary of the hypotheses analyses is presented in Table 3.

Discussions and conclusions
The purpose of the empirical study was to determine the precursors and outcomes of customer satisfaction in the South African hawkers/vendors in the leafy vegetable market. Nine hypotheses were reviewed and analysed using the structural modelling.
The empirical finding of the study shows that product quality, customer value and product price have insignificant influence on customer satisfaction in the South African hawker/vendor leaf vegetable market. This finding is inconsistent with the findings by Nyadzayo and Khajehzadeh (2016), Makhitha et al. (2016) and Flint et al. (2011), respectively, whose studies found that product quality, customer value and product price have significant influence on customer satisfaction. The explanation for this difference may be because the above studies were based on different samples to the current study, different industries/sectors, different products and settings. This may be as a result that in the South African context customers view product quality, customer value and product price as undifferentiated items which they take for granted that each supplier must be in a position to provide.
However, our research findings on communication and product mix show a significant influence by these constructs on customer satisfaction, in agreement with studies by Ndubisi and Wah (2005) and Wan et al. (2012).
Our findings also reveal that word-of-mouth, commitment, trust and customer loyalty are significantly influenced by customer satisfaction. This finding makes a major contribution to academic and practice because most literature, notably Morgan and Hunt (1994) support the notion that trust and commitment are precursors of customer satisfaction. Our findings contribute strongly to the academic field by further cementing the argument that the relationship between the variables (specifically trust, commitment, and satisfaction) are interdependent and multifaceted. One can, therefore, conclude that the relationship between these constructs is dependent on characteristics of samples used for the study, industry sector and product type amongst other factors. The study has tested the relationship between precursors and outcomes of satisfaction in the leafy vegetable market in South Africa. This study can benefit other researchers and practitioners who want to test the interrelationship of the constructs in this study to different sectors, especially in developing countries like South Africa.
The managerial implications of this study pertain to farmers/suppliers of leaf vegetables in that particular attention must be paid in making sure customers are satisfied. As evidenced in this study, customer satisfaction has a significant resultant of commitment, trust, loyalty and word-ofmouth, all of these are important ingredients for business success and achieving competitive advantages. This study provided insights into how suppliers/farming dealing with hawkers/street vendors need to take into consideration when building long-term relationships with their customers. In order for suppliers/farmers in this market, to build long-term relationships, there is a need to enhance strategies aimed at customer satisfaction. Therefore, our unique selling proposition is that communication, product mix, satisfaction, commitment, trust, word-of-mouth and loyalty are important relationship marketing dimensions in the South African leafy vegetable market. Marketing managers of leaf vegetables have to pay particular attention to these variables in order to succeed in this market.
In conclusion, we posit a conceptual model for satisfaction as a mediator between precursors and outcomes of business-to-business relationship marketing variables to Hawkers/street vendors in the leafy vegetable market, as shown by Figure 5.

Limitations and future research direction of the study
One of the limitations of this study can be attributed to its focus on a specific industry sector. The sample of study can be deemed to be too narrow. Also, the geographical area covered with the study can be said to not represent South Africa and Africans in general. The above-mentioned limitations can be said to be of little significance as Johannesburg is the economic hub of South Africa and Africa as a whole. Johannesburg is a city that represents a diverse population of the African continent.
The study explored constructs from the view of customers. The limitation of this is that suppliers/ farmers may view these in a different way. Therefore this calls for further studies from the viewpoint of suppliers/farmers.
One of the limitations of the study is the method of sampling. By using purposive sampling, the implication of this is that the findings cannot be generalised to other cities, countries and globally. The study focused on the leafy vegetable market and thus cannot be applied to business-tobusiness relationships to other industries.
Nevertheless, this article lays the foundation for future studies in the marketing of agricultural products as South Africa and Africa produce a lot of agricultural products for World consumption but very little marketing research literature on this sector exist.
This study supports the notion for more studies to be done on specific sectors/industries using different samples especially in South Africa, where there is a huge call for Africanisation of the curriculum. This objective of Africanisation of the curriculum can be achieved through such research which test theories based on European samples on African samples and settings.

Precursors Mediator Outcomes
Weak influence/significance Strong influence/significance Figure 5. Conceptual model for satisfaction as a mediator between precursors and outcomes of business-to-business relationship marketing variables to Hawkers/street vendors in the leafy vegetable market.