ANALYSIS OF PRODUCT QUALITY, SALES PROMOTION, BRAND IMAGES, AND AFTER-SALES SERVICE TOWARDS SAMSUNG GADGET PURCHASE DECISIONS

This study aims to determine the effect of simultaneous and partial product quality, brand image, sales promotion and after-sales service on purchasing decisions of Samsung smartphones at the Discovery Mobile Store in Sidoarjo. This research used quantitative method. The population and sample based on the questionnaire distribution to consumers who visited the Discovery Ponsel Store Sidoarjo, and were taken as 135 respondents. Data collection techniques used interviews, observation and questionnaires. The data analysis used reliability test, validity test, classic assumption test and multiple linear analysis test. The simultaneous and partial results of product quality, brand image, sales promotion and aftersales service have a significant effect on the purchase decision of Samsung smartphones at the Discovery Ponsel Sidoarjo Store because of the significance of <0.005.


INTRODUCTION
The smartphone industry is getting denser with the presence of Chinese producers. This has a lot of impact on the growth of the business of old players, one of them is Samsung.
Samsung has been known as the largest smartphone manufacturer with the most market share in the world. The position seems to be slowly going down, at least as the analysis predicts. UD Discovery is engaged in retail cellphones, especially Samsung. The number of companies that sell similar products in Surabaya, makes competition even tighter, but the quality of products, promotions, brands and aftersales. Is one of the marketing tools used by companies to achieve their marketing goals in the target market.
1. Analyze the effect of product quality, brand image, sales promotion and after-sales service simultaneously on Samsung smartphone purchasing decisions at Discovery Ponsel Sidoarjo Shop 2. Analyze the influence of product quality, brand image, sales promotion and after-sales service simultaneously on Samsung smartphone purchasing decisions at Discovery Ponsel Sidoarjo Shop Theoriticial Framework 1. Product Quality Product quality is quality which includes efforts to meet or exceed customer expectations that include products, services, people, processes, and the environment (Tjiptono, 2012).

Brand Image
Brand image is a set of consumer beliefs about a particular brand (Kotler and Armstrong (2001: 225) in (Hermansyur, H.., & Aditi, 2017) 3. Sales promotion Sales promotion is a form of direct persuasion through the use of various incentives that can be arranged to stimulate immediate product purchases and / or increase the amount of goods purchased by customers (Tjiptono (2008: 229) in (Mutia & Roisah, 2016)

After Sales Service
After-sales services are consumer perceptions of after-sales services (Pariyanto and Lukmandono, 2017)

Previous Research
Hermansyur, H.., & Aditi, 2017) entitled "The Influence of Product Quality, Brand Image, Price, and Promotion on the Purchase Decision of Honda Brand Cars in Medan City" The results of the study prove that there is a significant influence on product quality on car purchasing decisions the Honda brand in the city of Medan is 25%. There is a significant influence on the brand image of the decision to purchase a Honda brand car in the city of Medan is 46.7%. There is a significant effect on the price of purchasing decisions for Honda brand cars in the city of Medan is 29.7%. There is a significant effect of promotion on the purchase decision of Honda brand cars in the city of Medan is 40. 2% Parengkuan, Tumbel, & Wenas, (2014) entitled "Analysis of the Effect of Brand Image and Celebrity Endorser on Purchasing Decision on Head And Shoulders Shampoo Products at 24 Mart Manado" The results of this study stated that Brand Image and Celebrity Endorsement had a simultaneous effect on consumer purchasing decisions. Partially Brand image does not have a significant effect on consumer purchasing decisions. Partially Celebrity Endorsment has a significant effect on consumer purchasing decisions. Mutia & Roisah, (2016) entitled "The Influence of Sales Promotion and Service Quality on the Purchase Decisions of Honda Motorcycles at CV. The Endless Blessing of Ujungberung Motorbikes "The results of the study prove that the variable sales promotion and service quality have a positive and significant effect on purchasing decisions partially and simultaneously have an influence of 87.7% Afiff Yudha Tri Pariyanto, Lukmandono (2017), entitled "Effect of product quality, product price, promotion and after-sales service on purchasing decisions of Honda motorcycles (research beat type) The results of the study prove that all independent variables (product quality, price, promotion and after-sales service) have a positive effect t the purchase decision. The biggest positive influence on purchasing decisions of Honda Beat Mathic on Senior High School Albashtomi Students is on Product Quality variables with the test results of 4.822, then followed by price variables with a calculated value of 4.455, then promotion variables with a value of 2.985 and lowest after-sales service variable with a calculated value of 2.367.
Pratama & Dwiarta, (2017) entitled "The Influence of Brand Trust and Product Quality on Purchasing Decisions of Honda Beat Motorcycle Product Consumers in Karangpilang Sub-District, Surabaya City" The results of this study indicate that Brand and Product Quality Simultaneously and Partially have a significant effect on decisions purchase. Based on the data analysis concluded that there is a simultaneous influence between Brand Trust and Purchased Product Quality with an F value of 8,603 marks at 0,000. While the partial test shows that each variable has an effect on competency with the value of the Brand Trust is not equal to 2,950 marks 0,000 and Product Quality is 2,619 signs at 0,010.
Amron, (2018) entitled "The Influence of Image Brands, Brand Trusts, Product Quality, and Price on the Consumer's Buying Decision of MPV Cars", the results of this study indicate that there are influences on Brand Image, Brand Trust, Product Quality, and Price towards consumer decisions in buying MPV cars. Hatta et. al, (2018) entitled "Analysis of Product Innovation, Product Quality, Promotion, And Price, And Purchase Decisions", the results showed that respondents' perceptions of innovation and product quality, price, promotion, and the level of purchasing decisions were high; product innovation and promotion does not affect purchasing decisions. While product quality and prices influence purchasing decisions.
Brata at.al, 2017) entitled "The Influence Of Quality Products, Price, Promotion, And Location To Product Purchase Decision On Nitchi At PT. Jaya Swarasa Agung In Central Jakarta ", The results of the study show that product quality, price, promotion, and location influence purchasing decisions, both partially and simultaneously Nangoy And Tumbuan, (2018)

METHODOLOGY Type of Research
This type of research is causal research (looking for a cause and effect by using a hypothesis), where the object of this research is a case study conducted on consumers who visit the Sidoarjo Discovery Mobile Shop.
This study will use a quantitative approach, according to (Prof. Dr. sugiyono, 2016) quantitative method is a scientific approach that views a reality that can be classified, concrete, observable, and measurable, the relationship of variables is causal where the research data is in the form of numbers and analysis use statistics. The independent variables in this study are Product Quality, Brand Image, Sales Promotion, After-Sales Service, Purchasing Decision. The purpose of this study is more towards the results of generalizations, explaining phenomena in a more measurable manner and various evidences to be found. Data collection to obtain results of discussion, analysis and conclusions that can be justified.

Place and Time of Research
This research was conducted at the Discovery Mobile Shop in Sidoarjo. The research was conducted from June 2019 -July 2019.

Figure 1 : Conceptual Framework Population and Sample
The population in this study were consumers who visited the Discovery Ponsel Sidoarjo Shop, totaling 135 people. The sampling technique used is a non-probability sampling technique precisely purposive sampling. According to (Sugiyono, 2014) purposive sampling is a sampling technique of data sources with certain considerations. Based on these opinions, the research samples were consumers who visited the Sidoarjo Discovery Mobile Shop. which amounted to 135 people totaling 135 people.

Data Collection Method
The data sources used in this study use primary data and secondary data. Primary data are data obtained directly from the object of research. And secondary data, researchers get from data that has been processed by third parties, through books, libraries, libraries, and sources from the internet.

Multiple Regression Analysis Model
The data analysis technique used in this study is multiple regression analysis techniques. This analysis is intended to determine the effect of Product Quality (X1), Citra Merekt (X2), Sales Promotion (X3) and After-Sales Service on employee performance (Y): Y = a + b1X1 + b2X2 + b3X3 + b4X4 + e.

RESULTS AND DISCUSSION Reliability and Validity
Based on the research, the alpha cronbanch value is 0.881, which means that it is above the acceptance limit of 0.6. Therefore, the research instrument for the relationship between variables shows good consistency and acceptable data. Based on the research value of the correlation index for the relationship between the independent variables (Product Quality, Sales Promotion, Brand Image, After Sales Service) and the dependent variable (Purchasing Decision) below the significant level of 5% (0.05). Therefore, the data is considered valid.

Result of R Square
The value of R Square is 0.705, which means that all independent variables: Product Quality, Sales Promotion, Brand Image, After-Sales Service, and Purchase Decisions.  Figure 2: Heteroscedasticity Based on the graph above it can be seen that the distribution of data is irregular and does not form a specific pattern, and is spread over and below the number 0 on the Y axis, so it can be concluded that in this regression model there is no problem of heteroscedasticity. Figure 3: Results of Calculation of Normality Based on the graph above shows that all existing data are normally distributed, because all data spreads form a diagonal straight line, then the data meets normal assumptions or follows the normality line.

Hypothesis Testing F-Test
The F-test is used to determine all effects of all independent variables on the dependent variable. This test is done by comparing the Fcount value with Ftable value at α = 0.05 ..   Table 5 shows that thitung Product Quality (X1) is 1.992 with sig 0.001 smaller than 0.05 so Ho is rejected and Ha is accepted. Therefore Product Quality (X1) has a significant influence on Purchasing Decisions 2. Table 5 shows that thitung Sales Promotion (X2) is 2,263 with sig 0,000 smaller than 0.05 so H0 is rejected and Ha is accepted. Therefore Sales Promotion 3. Table 5 shows that the Brand Image tcount (X3) is 3.504 with sig 0,000 smaller than 0.05, H0 is rejected and Ha is accepted. Therefore Brand Image (X3) has a significant influence on Purchasing Decisions Product Quality for Purchasing Decisions

T-Test
The first hypothesis proposed states that Product Quality is partially towards the Purchase Decision of the Discovery Mobile Store in Sidoarjo, this has been proven by the value of the t test results 1.992.
Sales Promotion for Purchasing Decisions The second hypothesis proposed states that the sales promotion is partially towards the Purchase Decision of the Discovery Mobile Store in Sidoarjo, this has been proven by the results of the t test value of 2.263.
Brand Image of Purchasing Decisions The third hypothesis proposed states that the brand image is partially towards the Purchase Decision of the Discovery Mobile Sidoarjo shop, this has been proven by the results of the t test value 3,508.
After-sales service for purchasing decisions The fourth hypothesis proposed states that after-sales service is partial to the Purchase Decision of the Discovery Mobile Sidoarjo shop, this has been proven by the results of the t test value 5,768 Product Quality, Sales Promotion, Brand Image, and After-Sales Service Influence the Purchase Decision of the Shop Discovery Mobile Sidoarjo The fifth hypothesis proposed states that Product Quality, Sales Promotion, Brand Image, and After-Sales Service have a significant simultaneous effect on the Purchase Decision of the Discovery Mobile Sidoarjo Shop with the results of the F test value 38,081.