The Influence of Reference Group, Brand Image, and Internet Marketing on Buying Decision

with the development of technology and information as well as the rapid growth and spread of the population today, has an impact on all aspects of human life. One of them is to communicate fluently in conveying information. In marketing products there are several strategies used, such as the use of reference groups, brand image and internet marketing in determining purchasing decisions. The purpose of this study was to determine the effect of reference groups, brand image and internet marketing on purchasing decisions on As card products. The sampling method uses random sampling, with the method of multiple linear linear analysis the research shows that the reference group, brand image and internet marketing have an effect on the As card purchase decision. In this research, it is expected to be able to give a new view in marketing products, especially among the community.


INTRODUCTION
With the development of technology and information and the rapid growth and spread of population today, it has an impact on all aspects of human life. One of them is to communicate smoothly with such demands, making the companies engaged in telecommunications competing to issue SIM (subcider identity module) based on GSM technology. The following are the types of GSM operators in Indonesia, namely Tri, Indosat, Xl, and Telkomsel (As) with the number of GSM cards being marketed which means flexibility for consumers. The increasing trend of smartphone use in the community has made the growth of the internet in Indonesia continue to increase continuously. From the research data released by the Indonesian internet network user association (APJII) in 2017, it provides a clear picture of the trends in international users in Indonesia. According to MARKPLUS, the number of internet users in Indonesia in 2017 has reached 143.26 million people. The average penetration of internet users in major cities in Indonesia in 2014 was still 30-40 percent, whereas in 2017 MARKPLUS insight explained the increase in the range of 50-69 percent. Based on the explanation above, it was seen that the level of mobile and internet usage was greatly influenced by consumer demographic factors that are inseparable from consumer behavior so that buying decisions are influenced by two factors, namely internal and external. In the external environment in the mobile world there are many communities in the virtual world that will be entered by marketers so that the reference group plays an important role in the process of purchasing decisions.

LITERATURE REVIEW Marketing
Assuari'smanagement (2013: 12), the notion of marketing management is the activity of analyzing, planning, implementing, and controlling programs arranged in the formation, development, and maintenance of profits and exchanges / transactions through targets with the hope of achieving organizational goals.

Reference group
In a marketing perspective, a reference / reference group is a group that serves as a reference for a person in a buyer's decision and consumption.

Brand image
Tjiptono (2011: 112), brand image or brand description is a description of the association and consumer confidence in a particular brand. A number of quantitative and qualitative techniques have been developed to form consumer perceptions and associations for a particular brand. Kotler and Armstrong (2008: 237) internet marketing is a business enterprise to market products and services and build customer relationships through the internet.

Types of research
This research approach uses a quantitative approach to examine certain populations or samples, sampling techniques are generally done randomly, data collection uses research instruments, analysis which is quantitative or statistical in order to test what has been set. Sugiyono (2013) The

Place and time of the implementation
Of this research was conducted at schools, campuses and offices. The time for conducting research for two months. starting from December 2018 to January 2019.

Population and sample
The population used in this study were school children, students, and workers. The sample in this study were 160 respondents.

Methods of data analysis
Because this research is quantitative research, the data obtained from respondents through questionnaires are coded according to a 1-5 Likert scale and then tabulated using statistical analysis with the SPSS computer program. The collected data will be analyzed with several stages, first the validity test and the reliability of the research instrument, the classic assumption test in the form of normality test, multicollinearity test and hetereschedaticity test. Terakir tested the multiple linear regression model consisting of determination coefficient test, simultaneous significant test (F test) and partial significance test (T test) with the help of SPSS software version 18. Validity test on a variable reference group (X1), brand image (X 2), internet marketing (X 3), and purchasing decisions (Y) can be seen above, it appears that the value of R calculates each item exceeds that of R table 1.557. This means that each item statement can be declared valid.

Test Reliability
Testing the Cronbach's alpha statistics, the instrument is said to be reliable to measure reliable if it has an alpha value greater than 0.6. See the value of Cronbach's alpha and each variable. The level of relativity is generally accepted at a value of 0.6. Tests whose reliability is below 0.6 are considered unreliable.  Table 2, shows that the scores of the acun group statement items, brand image, internet marketing, andcard purchase decisions is reliable and in accordance with the high reliability value of the minimum reliability value of Cronbach's Alpha 0.6.

Data Quality Test Results
For data in the form of questionnaires, validity tests and reliability tests are needed to see data quality. This research has passed the validity and reliability tests.

Classical Assumption Test Results The classic
Assumption test is a test of the organization before conducting multiple linear analysis. This research has passed the normality test, multicollinearity and heterocedasticity.

Results of Multiple Linear Regression Analysis
The results of the calculation of multiple linear regression analysis using SPSS 18 are as follows:

2.
The reference group regression coefficient is 365 which means the reference group variable has a positive influence on the purchase decision regression coefficient value means that if the reference group variable increases by 1 unit then the purchase decision will increase by 365 units.

Regression coefficient of brand image -193 which means if the brand image variable
has a negative influence on the purchase decision variable. This regression coefficient value means that if the brand image variable decreases by 1 unit then the purchasing decision will also decrease by -193. The results of heteroscedaticity testing show the SIG value of the reference group variable (X1) of (0.002), brand image (X2) of (0.011) and internet marketing (X3) of (0.008) SIG variable value> 0.05 in group variables reference, brand image, and internet marketing. This means that the regression model did not occur in the variable heteroskedastisity Based on the table above, it can be seen that the regression model is not experiencing multicolonicity disorders. This can be seen in the tolerance value of each independent variable greater than 0.1, the result of VIF calculation also shows that the VIF value of each independent variable is less than 10. So it can be concluded that there is no multicollinearity between the independent variables in the regression model.

Figure 9. Normality Test Results
From the graph above it is known that the points spread around the diagonal line and follow the direction of the diagonal line, so that the normal distribution data is concluded.

1) The simultaneous influence of reference groups and internet marketing on As card customer satisfaction.
Based on the results of multiple linear analysis, it can be seen that the reference group, brand image, and internet marketing together affect customer satisfaction by 20.6% according to the coefficient of determination that is adjusted while the remaining 79.4% is influenced by other variables outside the variable in this study, customer satisfaction can be influenced by 2 factors, namely external and internal factors in this study indicate that external factors have a smaller influence compared to internal factors because communication tools today have become a major need of society. External factors consist of culture, social class, marketing strategy, especially in this study, namely the reference group, brand image, and internet marketingwhile internal factors consist of lifestyle, personality, self-concept, motivation, belief and knowledge.

2) Partial influence of reference groups on As card customer decisions.
The results showed that the reference group had a significant effect on the As card purchase decision. This means that consumers make As card purchases by considering the suggestions or opinions of the reference groups around them, such as family, friends, and neighbors is the respondent's reference group in observing, discussing, and seeking information about the As card.
In the case of the reference group variable, information has an important role in influencing respondents to make purchases on the As card, such as providing information and making the individual aware of the existence of a particular product or brand in this case katu As. By providing detailed information and insights about As cards, often sharing experiences to the invitation to use the As card. The positive sign of the regression model equation shows that the reference group has a positive influence on the As card customer decision. This is in accordance with the theory of Sumarwan (2011: 305) which says that the reference group significantly influences a person's behavior, for example in the buying process. Then supported by the results of research conducted by Makgosa et al (2007) state a significant influence between reference groups and purchasing decisions. Based on respondents' answers in this study for the reference group variables, through multiple regression analysis there is a positive relationship between the reference group and customer satisfaction, which is indicated by the regression coefficient of the reference group variable (X1) 0.206 which is positive. A positive sign on regression coefficient represents a unidirectional relationship between the influence of the reference group on the As card purchase decision, so that if the reference group (X1) is positive, the purchasing decision (Y) will increase as well.

3) Partial influence of internet marketingon As card purchase decisions as card purchase decisions
A positive sign of the equation of the regression model shows that internet marketing has a positive influence on. The partial test results show that internet marketing has a significant effect on purchasing decisions, where thevariable internet marketing has a dominant influence compared to the reference group in influencing the As card purchase decision. Because internet marketing is a partial r value that is greater than the reference group. This is related to the respondents in the study showing that the majority of respondents consisting of students and private employees are the majority of women aged between 15-25 years. Where they use more than one provider card other than the As card. But the main card they use as a communication device is the As card. Respondents have several reasons to use the As card to support their daily activities, such as interacting and communicating with friends and community in social media.

Conclusions
The conclusions of this study are 1. reference groups, brand image, and internet marketing, which have a significant simultaneous effect on As card purchase decisions for students, students, and workers. 2. The reference group has a partially significant effect on the As card purchase decision. 3. Internet marketing has a partially significant effect on As card purchase decisions for students, students, and employees.

Suggestions
Suggestions given: 1) For researchers Next researcher is suggested to conduct research outside the independent variables used in this study, for example promotion mix or other marketing mix that can be used to increase customer satisfaction 2) For companies Seeing higher competition in the internet world, in hope that you will always improve the quality and brand that is increasingly loved by the community, so that it can increase customer satisfaction.