Decrease Customer Satisfaction Research Articles

Exploring satisfaction of amusement parks in Indonesia

The rapid growth of amusement parks in Indonesia has elevated them to significant tourist hubs, prompting a detailed examination of visitor satisfaction within these settings. This study aims to analyze the satisfaction trends among tourists visiting the top 11 amusement parks in Indonesia and assess whether their ratings accurately reflect their satisfaction. Moreover, it investigates the factors influencing satisfaction levels, employing an adjusted rating method to dissect tourists' ratings and compare them with sentiment analysis results derived from provided reviews. While acknowledging the fluctuating performance of these destinations, with most showing signs of improvement, the study highlights that only 5 destinations within the sample exhibit comovement between adjusted ratings and sentiment analysis results. Furthermore, a closer inspection reveals that some destinations have successfully minimized the prevalence of negative sentiments expressed in reviews. However, there is still 1 destination that is of concern because it has decreased customer satisfaction as indicated by a decrease in score and the addition of negative sentiment.

Strategic Optimization of Conveyor Belt Splicing Solutions: Enhancing Competitive Edge in the Asia-Pacific Market (Case Study: Inspirare Luxiner Group)

The Asia-Pacific region, marked by rapid industrial growth and significant mining activities, offers both opportunities and challenges for companies in the conveyor belt splicing materials market. IL Group, known for its high-quality RARE System, has seen a decline in sales within this competitive environment. The centralization of manufacturing in Atlanta has led to long lead times and high logistics costs, reducing the company’s competitiveness. Moreover, insufficient after-sales support and integration challenges with client systems have further decreased customer satisfaction and retention. This research aims to identify the primary factors behind the RARE System’s decreased sales and to develop strategies for optimizing it to attract and retain clients. Additionally, it seeks to recommend business strategies to enhance IL Group’s competitiveness in the Asia-Pacific market. Data collection involved interviews and surveys with clients and internal stakeholders. The data was analyzed using thematic analysis, root cause analysis, SWOT & TOWS analysis, and Porter’s Five Forces framework. The study found that logistical challenges from centralized manufacturing, inadequate support, intense competition, and integration issues with client systems were key factors driving sales declines. To address these issues, the research recommends that IL Group establish regional manufacturing facilities to reduce costs and lead times. Improving customer support through regional centers and robust CRM systems is also essential. Investing in continuous R&D for product innovation will keep the product relevant and appealing. Implementing flexible pricing models and targeted marketing, along with forming strategic local partnerships, will further enhance competitiveness. By proposing these strategies, this research contributes to strategic business management. It offers practical solutions to enhance operational efficiency and market competitiveness. These strategies provide a structured approach to overcoming key challenges and achieving sustainable growth in the Asia-Pacific market.

Bi-GRU-APSO: Bi-Directional Gated Recurrent Unit with Adaptive Particle Swarm Optimization Algorithm for Sales Forecasting in Multi-Channel Retail

In the present scenario, retail sales forecasting has a great significance in E-commerce companies. The precise retail sales forecasting enhances the business decision making, storage management, and product sales. Inaccurate retail sales forecasting can decrease customer satisfaction, inventory shortages, product backlog, and unsatisfied customer demands. In order to obtain a better retail sales forecasting, deep learning models are preferred. In this manuscript, an effective Bi-GRU is proposed for accurate sales forecasting related to E-commerce companies. Initially, retail sales data are acquired from two benchmark online datasets: Rossmann dataset and Walmart dataset. From the acquired datasets, the unreliable samples are eliminated by interpolating missing data, outlier’s removal, normalization, and de-normalization. Then, feature engineering is carried out by implementing the Adaptive Particle Swarm Optimization (APSO) algorithm, Recursive Feature Elimination (RFE) technique, and Minimum Redundancy Maximum Relevance (MRMR) technique. Followed by that, the optimized active features from feature engineering are given to the Bi-Directional Gated Recurrent Unit (Bi-GRU) model for precise retail sales forecasting. From the result analysis, it is seen that the proposed Bi-GRU model achieves higher results in terms of an R2 value of 0.98 and 0.99, a Mean Absolute Error (MAE) of 0.05 and 0.07, and a Mean Square Error (MSE) of 0.04 and 0.03 on the Rossmann and Walmart datasets. The proposed method supports the retail sales forecasting by achieving superior results over the conventional models.

Customer satisfaction leading the intention to adopt battery electric vehicles with the moderating role of government support and status symbol

In response to the ongoing efforts to reduce pollution, the Chinese government is encouraging the use of battery electric vehicles (BEVs). People in China as a whole intend to supplement the government's initiative. Thus, this study aims to determine adoption intention for BEVs through environmental concerns, technophilia, social norms, price and battery cost, self-esteem, range confidence, satisfaction toward adopting BEV, financial incentives, non-financial policies, and status symbol by using the theory of planned behavior (TPB). PLS-SEM was followed, and data was collected through questionnaires using purposive sampling. A total of 508 questionnaires were used in the final analysis. Multiple regression was used for hypotheses testing. Environmental concerns, technophilia, social norms, self-esteem, and range confidence significantly enhance satisfaction toward adopting BEVs. Meanwhile, price and battery cost significantly decrease customer satisfaction towards adopting BEVs. Satisfaction towards adopting BEVs, government support (i.e., financial incentives, non-financial policies), and status symbols are leading to the intention to adopt BEVs. Government support is significantly moderate, but the status symbol does not moderate between satisfaction towards adopting BEVs and adoption intention for BEVs. This research suggests that policymakers and manufacturers focus on studying factors determining the intention to adopt BEVs. This initial research integrates environmental concerns, technophilia, social norms, price and battery cost, self-esteem, range confidence, satisfaction towards adopting BEVs, financial incentives, non-financial policies, status symbol, and adoption intention for BEVs in a single framework in light of TPB.

Examination of the selection of logistics service providers

The selection of logistics service providers plays a crucial role in the success of an organization's supply chain management. The new industrial revolution taking place today provides solutions that prioritize the issue of quality and also raise reliability to a new level, both on the service provider's and user's sides. As businesses grow and expand, the need for efficient and reliable logistics services becomes increasingly important. This study examines how to determine the criteria for the selection of logistics service providers in the current technological environment. The choice of logistics service provider has significant implications for an organization's operations and overall performance. Optimum selection can lead to enhanced customer satisfaction, cost savings, improved efficiency, and a competitive advantage. However, poor selection can result in logistical inefficiencies, decreased customer satisfaction, increased costs, and negative impacts on organizational reputation. Hence, careful consideration and evaluation of potential service providers are crucial. The digitized environment offers a solution for accessing large-scale databases, which provide well-founded decision evaluation plans based on a large number of samples. The quality characteristics influencing the logistics parameters were examined and weighted from the perspective of customer requirements. By exploring various aspects, we aim to shed light on the intricacies of this process and provide insights that can assist organizations in making informed decisions. We attempt to make the indices that appear as bottlenecks in the specified order more efficient using an optimization procedure.

Implementation of Augmented Reality Shopping in E-Commerce to Increase Customer's Purchase Intention

E-commerce has grown immensely in the past few years, especially during the Covid-19 pandemic. This condition brings severe conditions. Most traditional business owners must shift and implement e-commerce into their business models. Although e-commerce has many advantages, it also has limitations. The limitation of e-commerce is that it is difficult for customers to visualize the products they will buy in the real world. Most E-commerce applications only allow customers to see images and reviews of the products they want to buy through the screen of their devices. This situation can decrease customer satisfaction if the products they believe do not match the images. This research aims to help solve the limitations of e-commerce applications by implementing Augmented Reality to help customers visualize the products they buy. The researcher developed an Android-based mobile AR application using Unity and the Vuforia engine. After creating our AR application, we surveyed 46 participants to test our AR application. The researcher used Likert Scale with a scale of 4. The result is that almost all participants agreed that AR makes it easier to visualize the product purchased from e-commerce. An average score of 3.6 shows that most participants strongly agree that AR positively influences their decision-making to buy products.

Customer Satisfaction with Telephone-Based Self-Service Technology: Investigating the Role of ‘Gender’ of the Voice Assistant

ABSTRACT Digitalization across industries is increasingly changing the way customers interact with service providers. One of the most significant influences of digitalization on service outcomes is driven by technology-enabled services i.e. self-service technologies (SSTs). Despite continuous advancement of service delivery from traditional methods to modern SSTs, the technology-oriented interfaces differ in their level of complexity which may affect customer satisfaction. Two independent experiments were undertaken to observe customer satisfaction with telephone-based SSTs. Study 1 featured a 2 (Level of SST Complexity: High/Low) X 2 (Gender of Voice Assistant: Male/Female) between subjects design, while a follow-up study featured a 2 (Service Delivery Outcome: Success/Failure) X 2 (Gender of Voice Assistant: Male/Female) between-subjects factorial design. Results confirm the proposition that a higher level of SST complexity is more likely to lead to decreased customer satisfaction and intention to continue using the SST and this effect is more when the telephone-based SST uses a female voice assistant rather than a male voice assistant. Findings of the follow-up study suggest that customer dissatisfaction following a telephone-based SST failure is more likely with a male voice assistant rather than a female voice assistant. Results are critical for customer-centric firms that depend on effective implementation of SSTs.

The clock is ticking—Or is it? Customer satisfaction response to waiting shorter vs. longer than expected during a service encounter

Customer waits are commonplace in retail settings. To develop efficient wait management strategies, retailers need insights into how customers respond to waiting during service encounters. An intuitive insight supported by extensive research is that a longer wait duration decreases customer satisfaction. However, the same wait duration might have different effects on customers depending on whether it is shorter or longer than what customers expected. To address this question, we draw upon the research on time value and predict asymmetry in the customer satisfaction response to waiting shorter versus longer than expected: Though the clock is often said to be ticking, waiting longer than expected leads to a minor decrease in satisfaction, whereas waiting shorter than expected substantially increases satisfaction. We provide evidence for this asymmetric effect across three studies and identify two boundary conditions: if the source of the expectation is external (e.g., wait time estimate provided by the retailer) or if the wait is much longer than expected. Overall, our research encourages retailers to put the customer response to waiting into perspective: Customers will tolerate waiting longer than expected, up to a certain point.

Employee emotional competence and service recovery satisfaction: the mediating role of consumer forgiveness

PurposeEmployees' emotional competence (EEC) is gaining increasing attention in service failure and recovery research. This study investigates the mediating role of consumer forgiveness between perceived EEC and recovery satisfaction among casual dining consumers. Additionally, this study examines the effect of perceived EEC on recovery satisfaction across process failure vs outcome failure.Design/methodology/approachA critical incident technique (CIT) in conjunction with a self-administered online survey was carried out. Using the snowball sampling technique, a total of 204 useable responses were collected. To test the hypotheses, this study used partial least squares structural equation modeling (PLS-SEM).FindingsThe study finds that perceived EEC influences service recovery satisfaction. Additionally, the study identifies the mediating role of consumer forgiveness in the relationship between perceived EEC and recovery satisfaction. Multi-group moderation analysis shows that the relationship between perceived EEC and recovery satisfaction is weaker in process failures as compared to outcome failures.Practical implicationsBased on obtained results, this study recommends that after service failure consumer forgiveness and subsequent recovery satisfaction can be obtained with perceived EEC. To do so, managers need to incorporate emotional competence while recruiting and training the employees. Moreover, managers need to train employees on failure types and respective recovery strategies. Lastly, the study suggests that in emerging markets managers should pay greater emphasis on process failure, because such failure decreases customer satisfaction greatly than outcome failure.Originality/valueTo the authors' knowledge, this is the first study that investigates the impact of perceived EEC on consumer forgiveness which subsequently determines the recovery satisfaction in the emerging markets. It extends the application of the emotional contagion and affect infusion theories by exposing the effect of perceived EEC on recovery satisfaction through consumer forgiveness. In addition, the study provides insights that the influence of perceived ECC on recovery satisfaction significantly varies across service failure types.

Effect of Service Quality, Price and Promotion on Customer Satisfaction at PT. Mestika Power

Researchers took the object of research at PT. Mestika Sakti, due to a decrease in customer satisfaction. Customer satisfaction is a stimulus for customers to rate a product or service after using it. Quality of service, price and promotion is one of the causes of decreased customer satisfaction. The research approach used is a quantitative approach. The type of research used in this research is descriptive quantitative. In accordance with the research objectives, the nature of this research is descriptive explanatory. The population used is the company's customers as many as 124 people and the sample of this study amounted to 95 people obtained from the Slovin formula. used to test the validity and reliability are as many as 30 customers at the same company. The results of linear regression analysis show Customer Satisfaction = 10,730 + 0.173 Service Quality + 0.177 Price + 0.279 Promotion. The results showed that partially service quality, price and promotion had a significant influence on customer satisfaction at PT. Mustika Sakti. The results of the study simultaneously obtained that service quality and promotion had a significant effect on customer satisfaction, while price had no significant effect on customer satisfaction. The value of Adjusted R Square is 0.367 which means that it implies that the influence of the independent variable on the dependent variable is 36.7% and the remaining % is the influence of other independent variables.

Service quality assessment and enhancement using Kano model.

Success in the retail sector is highly dependent on customer satisfaction. Maintaining a competitive edge depends upon the service providers knowing and enacting what is important to their customers. Multiple studies have employed various research approaches to identifying characteristics of customer satisfaction in different sectors as well as retail sector. However, very few have determined such characteristics using multiple approaches simultaneously in the retail store. This study aims to identify, categorize, and rank the retail store attributes, based on their effects on customer satisfaction. A survey focusing on retail store characteristics that impact customer satisfaction was developed and distributed. Over 400 responses were collected and evaluated, using the Kano model. Results showed that visually appealing facilities and error-free transactions are of prime importance to customers. They are taken for granted, but their absence plays a significant role in customer dissatisfaction. An easy-to-navigate store layout and readily available service increase customer satisfaction, but their absence doesn't decrease customer satisfaction. Clean public areas and modern-looking equipment are important, and improvements to them increase customer satisfaction at a proportional rate. The findings of this study will assist service providers in realizing the relative importance of the attributes of retail stores and in evaluating the impacts of their current practices on customer satisfaction levels. Such importance will also help retail sector policy makers in mandating policies focusing on must-have attributes to preserve customer satisfaction.

The effects of tip distribution policies: Servers’ keeping vs sharing/pooling tips affects tippers’ sentiments but not tip-giving

The U.S. Department of Labor recently loosened regulations about who can and cannot participate in tip-sharing and/or pooling and there is interest among restaurateurs and others in expanding use of these policies as a way to reduce front and back-of-house pay differences, so understanding their impact on servers and customers is of practical as well as theoretical value. Accordingly, an online, hypothetical scenario experiment was conducted to examine the effects of different tip distribution policies on consumer sentiment and tipping. Results indicated that consumers (especially those intrinsically motivated to tip) prefer servers to keep their individual tips, rather than share or pool their tips with others, but that tip distribution policies have no effect on the tip amounts that people say they would leave. These findings suggest that: (i) altruistic and reciprocity motives for tipping are primarily directed toward service workers directly interacting with the consumer, (ii) consumers do not see the dilution of severs’ tips under tip-sharing and tip-pooling (vs tip-keeping) as effecting the future-service or social-esteem that any given tip will buy, (iii) tip sharing and pooling may decrease customer satisfaction and re-patronage, and (iv) there is little reason for policy makers to fear that tip-sharing and tip-pooling (vs tip-keeping) will adversely affect tip revenues. • Consumers prefer that servers keep rather than share or pool tips. • Greater intrinsic (but not extrinsic) motivations for tipping enhance this effect. • However, tip distribution policies do not affect tip amounts. • Tip distribution policies deserve more research attention.

Financial Assessment on Designing Inventory Policy by Considering Demand, Lead Time, and Defective Product Uncertainties: A Monte Carlo Simulation

Inventory is one of the main components in supply chain. However, it is not easy to design inventory policy under uncertainties. The frequent occurrence of overstocks increases the company's financial expenditure. Otherwise, stockout decreases customer satisfaction and damage the company's image. This study aims to provide monte carlo model to design inventory policy with the aim of maximizing net income with a variety of uncertainties, one of the uncertainties is defective product because of the travel from suppliers. To handle the complexity and uncertainty of problem, a Monte Carlo simulation is used with spreadsheet-based representation. To test the reliability of the model, guitar company is used as relevant use case with uncertainty adhered ‘the greater number of order quantity, the greater likely the defective guitar will be’. The verification & validation process, experimental design, and alternative selection are also done with statistical tests. Based on the simulation result, it is known that changing the reorder point to 80 and the order quantity to 90 gives the best result which can increase net income by 0.44% compared to the initial net income. In addition, the number of stockouts has decreased.

INFLUENCE ANALYSIS OF REWARDS & MOTIVATION, COMMUNICATION, DEVELOPMENT, SUPPORT SYSTEM, EMPLOYEE SELECTION, EMPLOYEE RECRUITMENT, AND HEALTHY WORK ENVIRONMENT ON INTERNAL MARKETING (CASE STUDY AT PORT DIVISION BONTANG COAL TERMINAL PT INDOMINCO MANDIRI)

Internal Marketing is the important aspect at the organization to measure business performance. The job of internal marketing is to recruit, train and motivate employees who can serve customers well. Without being actively promoted, internal marketing can have a negative impact on service quality, which can lead to decreased customer satisfaction and profitability. This study is focused on the services division especially in port division Bontang Coal Terminal PT IMM. Researchers took research data through a Google Form questionnaire. There are 84 respondents were recorded as filling in the questionnaire to test all the hypotheses. There are 7 indicators used to assess internal marketing. The data analysis used PASW Statistics 18 to test the level of validity and reliability, to test the results of the hypothesis, the researcher used SEM PLS to determine the relationship between variables. The findings of this study are that the Rewards and Motivation, Communication, Development, Support System, Employee Selection, Employee Recruitment, and Healthy Work Environment have positive significant on Internal Marketing

Factors influencing the Buying intention toward paid mobile application; a mediating moderator approach

Although there is supposed to be tremendous growth potential for paying for app obtaining besides the mobile game industry, there is slight understanding of what drives game thespians to make such acquisitions. The model was tested using a questioner to gather data for the Pakistan game societies. Using free edition of the paid mobile app, 310 replied with data collection. Multiple regressions were used for study model evaluation. The results show that satisfaction with mobile games substantially affects a player's intention to make paid games to buy. The supposed spirited values (regularity, flow, touch, and accomplishment) have a significant effect on all players' enjoyment but fail to have a significant impact on the buying intent. Satisfaction has been found to have a partial effect on a performer's intent to pay app. Moderating effect of the negative results on the willingness to purchase pay apps from high price. Our study revealed higher purchase prices which decreased customer satisfaction. This study gives a deeper understanding of how values promote enjoyment among all players in the game, and paying players' buying intentions. We also have further insight into marketing campaigns for mobile game applications.

Evaluation of the size of time windows for the travelling salesman problem in delivery operations

A great challenge in operational research is to apply time-efficient algorithms to find the optimal solutions to the travelling salesman problem (TSP) and its many variations. The TSP with time windows (TSPTW) arises due to intense pressure for business to improve customer service. As online shopping becomes more popular, customer satisfaction increases if customers can decide when their orders are delivered to them. Customers may choose a time window, which is defined by an earliest delivery time and a latest delivery time, during which the package is delivered. Delivering packages to multiple customers is a typical TSPTW. One main challenge for a delivery business is to determine the size of the time window (i.e., the difference between the latest and earliest delivery times), which affects delivery cost and customer satisfaction. Although many previous studies investigated the TSPTW, none of those focused on the size of time windows. This study is the first that experiments with different time window sizes and determines their impact on tour duration, customer satisfaction, and solution time of the optimal delivery routes. The experiment results show that increasing the size of the time window decreases tour duration and customer satisfaction and increases solution time. Decreasing the size of the time window increases tour duration and customer satisfaction and decreases solution time. A small solution time is necessary for the scheduling of deliveries to many customers. A large solution time prevents a delivery business from delivering packages using optimal routes, which increases delivery cost and decreases customer satisfaction. The results of this study indicate that a general guideline for business is to allow customers to choose a time window size that is within the cost limit but is sufficiently small to maximize customer satisfaction and optimize delivery routes.

Selling in the Digital Age

Advances in technology have revolutionized consumer buying behavior. The internet has provided customers with a cheap source of information that can help them make informed buying decisions. However, many salespeople are still relying on the classic model of selling, which is based on the assumption that customers are uninformed, uncertain, and undecided when they meet a salesperson. This model suggests that salespeople, as knowledgeable gatekeepers of information, should guide customers through the sales process. For example, solution selling suggests that the salesperson should diagnose customer needs and then recommend the right products/services to fulfill those needs. The challenger sales model suggests that a seller should actively teach customers, tailor the sales process to them, and take control of the customer conversation In this report, authors address the question: How does employing the classic sales model with customers with greater and lesser preference certainty affect the sales interaction outcomes of (1) purchase probability, (2) sales revenue, and (3) customer satisfaction? In their first study, the authors collected data from 356 individual sales interactions in 15 different stores of a U.S.-based retailer of durable goods over four months. They show that customers with greater preference certainty have a lower purchase probability when the classic sales model is implemented. (i.e., from more than 80% to 60%). Further, the revenue from a sales interaction is reduced by more than 25% when salespeople use the classic sales model on customers with higher levels of preference certainty. Finally, when faced with customers who have a good idea of what they want to buy, salespeople may decrease customer satisfaction by using the classic sales model technique. A second, scenario-based experiment corroborated and replicated the first study, using Amazon’s Mechanical Turk. This study found that, under high levels of preference certainty, challenging the customer results in a lower likelihood to purchase during the shopping visit. Further, these findings were found to be unrelated to price. These findings point to a need to transform the way that salespeople interact with customers. The authors offer two ways that managers can benefit from this research, and help their salespeople move beyond the classic sales model. Training. Sales managers can teach their salespeople about the importance of acknowledging the differences among customers along the decision-making process and train them on the appropriate tactic in each stage. Lead generation. Customer relationship management technology now makes it possible to monitor customers’ research behavior and to index prospects depending on their stage in the process; therefore, this technology can assist salespeople in adopting the appropriate sales tactic. Finally, new sales models should revisit and redefine assumptions of the standard paradigm of selling.

The Impact of Scope Creep on Project Success: An Empirical Investigation

Advocates of software engineering and software project management stated in the literature that creeping of scope is one of the most common causes for the failure of software projects. Also, advocates believed that it could occur in almost every software project, which leads to compromise in quality, delayed schedules, increase cost and decreased customer satisfaction. However, the lack of empirical evidence demands a comprehensive investigation to identify the factors of scope creep and to propose a conceptual framework to empirically evaluate the impact of scope creep on software project success. To determine the scope creep factors in this study, two exploratory methods, i.e. a Systematic Literature Review (SLR) and interview from experts are performed. Following the analysis of these methods, a conceptual framework is proposed. To empirically evaluate the proposed conceptual framework, data is collected through a survey method. Next, the collected data is analyzed through Partial Least Squares' Structural Equation Modelling (PLS-SEM). From the results, it is evident that the identified factors of scope creep are negatively associated with software project success. The results of empirical evaluation also second the findings of SLR. The outcome of the study may help the practitioners to understand the dynamics of factors, which undermine scope creep in software SMEs and to assist them in the development of effective control and mitigation strategies, therefore, to increase the project success rate.

Enhancing Service Quality to Increase Customer Satisfaction: A Phenomenological Method of Low Cost Carrier Airlines Companies in Indonesia

The air transportation service industry sector is growing rapidly in Indonesia. Various strategies are done by airlines. However, there are also various problems that impact on the decline in quality of service resulting in the decreased customer satisfaction. The research is carried out to know what the problems and challenges faced on service quality (SERVQUAL) in Low Cost Carrier (LCC) Airlines Companies. In-depth interviews were employed in this study, also the questionnaires to triangulate the instruments. The research proved that the Low Cost Carrier (LCC) Airlines Companies still need a lot of improvements for the sake of comfort and safety

The Language Backfire Effect: How Frontline Employees Decrease Customer Satisfaction through Language Use

Extant marketing research holds that customers prefer frontline personnel to speak the customers’ first language. Furthermore, current managerial practices instruct frontline employees to either use the customers’ first language or, in international settings, to use English. Through five studies in different retail and service contexts, we identify situations where the opposite is true. The results of the first two studies suggest that if customers initiate contact in a second language, the frontline employee’s switch to the customer’s first language constitutes an identity threat leading customers to feel less satisfied; an effect we term the language backfire effect. Our third study extends these results to a domestic context to test for the impact of linguistic acculturation on how immigrant customers perceive frontline employees’ language switch. The fourth study replicates the findings in a real-life retail context. These results present a paradox for marketing research: although frontline employees switch to customers’ first language to accommodate them, these actions might not have the desired consequences. Having identified and described the problem of the language backfire effect, our final study introduces and verifies a managerially actionable solution: combining the language switch with a language proficiency compliment offsets the language backfire effect.