## 2 Background
### Cognitive Effort and RA Transparency  
In the online consumer context, without the recommendations of an AI-based RA, users, throughout their decision-making process, must gather and consider all the decision relevant information [16]. When this information load becomes too excessive for the user's limited capacity in processing information, cognitive fatigue and confusion emerge [17]. Information overload is then reached, thus negatively affecting the efficiency and effectiveness of the users' decisions [5]. The users' perceived cognitive effort, required to process information while making a decision, has been shown to diminish with the usage of RAs [18]. However, by adding explanations exposing the logical reasoning behind the recommendations of an RA, the cognitive effort of the users increases [11]. Hence, without these explanations, the recommendations of an RA would be ignored by the users throughout their decision-making process. Nonetheless, with these explanations, information overload could be reached by the users, thus negatively affecting their decision-making process. Consequently, the need for transparency and the cognitive effort needed to understand and access these explanations must be rightfully balanced. Impact of Transparency and Cognitive Effort on Users' Perceptions, Usage Behavior, and Decision Quality  
Past research on RAs focusing on the online consumer context shows the impact of transparency and cognitive effort, when these two factors are not rightfully balanced, on users' perceptions (i.e., source credibility, sense of control, decision quality, and satisfaction), usage behavior, and decision quality. **Source credibility. ** To perceive the recommendations of an AI-based RA as credible, users need to recognize these suggestions as believable [19]. Multiple dimensions have been shown to influence source credibility (e.g., trustworthiness, expertise, attractiveness) [20]. However, prior research on recommender systems' perceived credibility has mainly focused on two key dimensions:trustworthiness and expertise [21; 22]. The RA is perceived as trustworthy by the users when its recommendations are recognized as reliable and honest [23]. The RA is considered an expert when it is identified by the users as having the ability and the skills to recommend effectively [7; 23]. Therefore, users perceived source credibility can increase with the help of transparency [24]. Explaining the logical reasoning behind the recommendations of an RA establishes users' trust and shows the expertise of these suggestions [16]. Furthermore, according to the literature, users' trust also varies with the RA's perceived ease of use (PEOU) [8]. This RA's PEOU is negatively affected when the cognitive effort of the users increases [23]. **Sense of Control. ** In riskier contexts (e.g., car purchase), users that do not understand the recommendations of an RA have been shown to ignore these recommendations throughout their decision-making process [25]. Hence, without perceiving a sense of control over the RA's recommendations, users will not consider these suggestions [26]. This feeling of control has been shown to be enhanced with transparency [15]. Although a transparent RA increases cognitive effort, transparency is critical for users to feel a sense of control over the RA's recommendations [27]. In addition, according to the literature, explaining the logical reasoning behind the recommendations of an RA partially, through simple explanations, is more effective on the users perceived sense of control than exposing the details of its algorithm completely [15; 25]. **Decision quality. ** Decision makers, in order to maximize the accuracy of their decisions (i.e., decision quality), must invest more cognitive effort [23]. However, decision makers are generally looking to maximize the accuracy of their decisions and minimize the cognitive effort invested [28]. Evaluating all the available alternatives in depth, through a complex decision-making process, is normally impossible for users [29].