Tailoring the Presentation of Plans to Users ’ Knowledge and Capabilities
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英文作文关于报告Title: The Art of Delivering an Effective Presentation。
Presenting a report is not merely a task of conveying information but an art of engaging and persuading an audience. Whether it's in a classroom, boardroom, or conference hall, mastering the art of presentation can significantly impact the reception and understanding ofyour message. In this essay, we will explore key strategies for delivering an effective presentation.First and foremost, effective presentations are built upon thorough preparation. Before stepping in front of an audience, one must invest time in researching the topic, organizing thoughts, and structuring the content in a coherent manner. This preparation ensures that thepresenter is knowledgeable and confident, which in turn instills trust and credibility in the audience.Moreover, a successful presentation relies heavily oneffective communication skills. This includes not only the ability to articulate ideas clearly but also to engage the audience through dynamic delivery. Utilizing vocal variety, gestures, and body language can help captivate theattention of the audience and maintain their interest throughout the presentation.Visual aids also play a crucial role in enhancing the clarity and impact of a presentation. Whether it's slides, charts, or graphs, visual representations can helpreinforce key points and facilitate understanding. However, it's essential to use visual aids sparingly and ensure they complement, rather than distract from, the presenter's message.In addition to verbal and visual communication, effective presentations often incorporate storytelling techniques. Human beings are naturally drawn to narratives, and weaving a compelling story into your presentation can help create an emotional connection with the audience. Personal anecdotes, case studies, or real-life examples can make abstract concepts more relatable and memorable.Furthermore, successful presenters are adept at adapting to their audience and context. This involves tailoring the content, tone, and style of the presentation to suit the preferences and expectations of the audience. Whether it's adjusting the level of technical jargon or incorporating cultural references, customization demonstrates attentiveness and respect for the audience's needs.Another key aspect of delivering an effective presentation is managing time effectively. Time is a precious resource, and audiences appreciate presenters who respect their schedules. Practicing the presentation beforehand and being mindful of time constraints can help ensure that the content is delivered in a concise and organized manner.Lastly, a strong conclusion is essential for leaving a lasting impression on the audience. The conclusion should summarize the key points, reiterate the main message, and leave the audience with a clear call to action or takeaway.Ending on a memorable note ensures that the presentation resonates with the audience long after it's over.In conclusion, delivering an effective presentation is a multifaceted skill that requires careful preparation, effective communication, engaging delivery, and audience adaptation. By mastering these strategies, presenters can captivate their audience, convey their message with clarity and impact, and ultimately achieve their desired outcomes.。
文件传达提纲范文When it comes to writing a file conveying outline example, it is important to remember the purpose of the document. 文件传达提纲样本是为了确保信息传达的清晰和准确,使读者能够快速了解文件的主要内容。
This means that the outline should be structured in a way that is easy to follow and understand, highlighting the key points and supporting details. 提纲应该包括文件的标题、摘要、主体内容和结论等部分,以便让读者快速浏览并获取重要信息。
By clearly outlining the document, readers can easily navigate through the information presented and grasp the main ideas without getting lost in the details. 通过清晰的提纲,读者可以更好地理解文件的主旨,更有效地获取信息,不至于在细节中迷失方向。
Furthermore, a well-structured outline can also help the writer stay organized and focused, ensuring that all important points are addressed in a logical order. 此外,一个结构良好的提纲还可以帮助作者保持组织和集中注意力,确保所有重要点按照合乎逻辑的顺序得到处理。
When creating a file conveying outline, it is essential to consider the target audience and their needs. 在创建文件传达提纲时,需要考虑目标读者及其需求。
How to Write the Best Title for a Speech?When it comes to delivering a speech, the title plays a crucial role in capturing the attention of the audience. A well-crafted title not only grabs the audience’s interest but also gives them a clear idea of what to expect from the speech. In this article, we will explore some tips and guidelines to help you write the best title for your speech.1. Be Concise and ClearThe first rule for writing a great speech title is to keep it concise and clear. Avoid using long and convoluted sentences that may confuse the audience. Instead, choose words and phrases that convey your main message effectively in a succinct manner.A concise title not only grabs attention but also sets the tone for the speech.2. Identify the Main IdeaA good speech title should clearly indicate the main idea or theme of the presentation. Take some time to identify the central message or purpose of your speech and try to encapsulate it in a few words. By doing so, you can create a title that immediately resonates with the audience and intrigues their curiosity.3. Use Powerful and Descriptive WordsThe choice of words in your speech title can make a significant impact on its effectiveness. It is important to use powerful and descriptive words that evoke emotions and engage the audience. Consider using action verbs, adjectives, or adverbs that bring your topic to life and make it more appealing.4. Make it MemorableA memorable speech title is more likely to stick in the minds of the audience. Aim to create a title that leaves a lasting impression and piques their interest. You can achieve this by using wordplay, alliteration, or incorporating humor. However, ensure that the title remains relevant to the content of your speech.5. Consider the AudienceWhile crafting a speech title, it is essential to consider your target audience. Think about their interests, backgrounds, and expectations. Tailoring the title to their preferences can make it more appealing and increase their curiosity. It is important to strike a balance between being engaging and accurately representing the content of your speech.6. Seek FeedbackOnce you have drafted a few potential titles, seek feedback from trusted friends, colleagues, or mentors. They can provide you with valuable insights and suggestions to help refine your title. Consider their input and make necessary improvements to ensure that the final title is the best reflection of your speech.7. Be Mindful of LengthThe length of your speech title also matters. Ideally, it should be neither too short nor too long. A very short title may not accurately convey the message, while an overly long title can be overwhelming and lose its impact. Strive for a title that is concise yet informative, capturing the essence of your speech in a few words.ConclusionWriting the best title for your speech requires careful consideration and attention to detail. Start by identifying the main idea and crafting a concise and clear title that resonates with your audience. Use powerful and descriptive words, make it memorable, and be mindful of the length. Lastly, seek feedback and refine your title until it becomes the perfect representation of your speech. Remember, a well-crafted title can significantly enhance the impact of your speech and captivate your audience from the very beginning.。
商品使用说明书作文英语Product user manuals are an essential component of any product or service. They provide crucial information to consumers on how to properly use and maintain a product, ensuring its longevity and safe operation. These manuals serve as a bridge between the manufacturer and the end-user, guiding them through the intricacies of the product and empowering them to make the most of their purchase.At the heart of a well-crafted user manual lies a deep understanding of the target audience. Manufacturers must meticulously consider the diverse backgrounds, technical proficiencies, and language preferences of their consumers. By tailoring the content and presentation to meet these varied needs, they can create a user-friendly experience that enhances the overall satisfaction with the product.One of the primary functions of a product user manual is to provide clear and concise instructions on how to assemble, operate, and maintain the product. This information is typically organized in alogical and intuitive manner, with step-by-step guides accompanied by visual aids such as diagrams and illustrations. This approach not only helps users navigate the manual effortlessly but also reduces the likelihood of confusion or mistakes during the setup and usage process.Beyond the practical aspects of product operation, user manuals also serve to educate consumers on the features, capabilities, and limitations of the product. By delving into the technical specifications, safety guidelines, and troubleshooting tips, these manuals empower users to make informed decisions and maximize the utility of their purchase. This knowledge can be particularly valuable for complex or specialized products, where a deeper understanding of the product's inner workings can be the difference between a satisfactory and an exceptional user experience.Effective user manuals also play a crucial role in fostering brand loyalty and customer satisfaction. When users are provided with comprehensive and user-friendly guidance, they are more likely to develop a positive perception of the brand and its commitment to supporting its customers. This, in turn, can lead to increased customer retention, word-of-mouth referrals, and a stronger overall brand reputation.However, crafting an exceptional user manual is no easy feat.Manufacturers must carefully balance the need for detailed technical information with the desire to create a concise and accessible document. This requires a deep understanding of the target audience, as well as a keen eye for effective communication and design. The use of clear and concise language, the incorporation of visual aids, and the organization of content in a logical and intuitive manner are all essential elements of a well-designed user manual.Moreover, the digital age has brought about a shift in the way user manuals are delivered and accessed. Many manufacturers now offer digital versions of their manuals, either as downloadable PDFs or interactive online resources. This transition has brought about a range of benefits, including the ability to regularly update the content, the incorporation of multimedia elements, and the ease of accessibility for users. By embracing these technological advancements, manufacturers can further enhance the user experience and provide their customers with a more comprehensive and engaging resource.In conclusion, product user manuals are a vital component of the consumer experience. They serve as a bridge between the manufacturer and the end-user, providing crucial information on the proper use and maintenance of a product. By crafting user-friendly and informative manuals, manufacturers can not only empower their customers but also foster brand loyalty and customer satisfaction. Asthe digital landscape continues to evolve, the role of user manuals will only become more crucial, and manufacturers must stay ahead of the curve to deliver exceptional customer support and a seamless user experience.。
采风总结汇报演讲技巧pptTitle: Mastering Effective Presentation Skills for Field Report SummarySlide 1: Introduction- Introduce yourself- Briefly explain the purpose of the presentation: to share key points and techniques for delivering an impactful field report summary presentationSlide 2: Importance of Effective Presentation Skills- Explain the significance of effective presentation skills- Emphasize the impact it can have on the audience's understanding and engagementSlide 3: Know Your Audience- Discuss the importance of understanding the audience's background and needs- Explain how tailoring the presentation to their expectations can improve its effectivenessSlide 4: Structure and Organization- Highlight the importance of a clear structure for the presentation - Discuss techniques for organizing the content logically and coherentlySlide 5: Visual Aids- Explain the benefits of using visual aids in presentations- Discuss different types of visual aids (charts, graphs, images) and the appropriate situations for their useSlide 6: Simplify Complex Information- Provide tips for breaking down complex information into simpler terms- Emphasize the importance of using plain language to enhance audience understandingSlide 7: Engaging with Non-Verbal Communication- Discuss the impact of body language, facial expressions, and gestures in presentations- Provide suggestions for effective non-verbal communication techniquesSlide 8: Practice, Practice, Practice- Highlight the importance of practicing the presentation multiple times- Offer strategies for rehearsal, such as recording oneself or conducting a mock presentationSlide 9: Time Management- Explain the significance of managing time effectively during the presentation- Suggest techniques for maintaining a steady pace and avoiding rushed or prolonged segmentsSlide 10: Engaging the Audience- Discuss techniques for actively involving the audience during the presentation- Suggest methods such as asking questions, seeking opinions, or incorporating interactive activitiesSlide 11: Handling Questions and Feedback- Provide tips for responding to audience questions effectively- Discuss strategies for handling feedback professionally and constructivelySlide 12: Conclusion- Recap the key points discussed throughout the presentation- Encourage the audience to apply these techniques in their future field report summary presentationsSlide 13: Additional Resources- Provide a list of recommended books, articles, or websites for further learning on presentation skillsSlide 14: Questions and Answers- Allocate time for the audience to ask questions or seek clarificationSlide 15: Thank You- Express gratitude to the audience for their time and attention- Provide contact information for any follow-up questions or discussionsNote: The above content is an outline for a PowerPoint presentation. Each slide should contain concise bullet points and visually appealing graphics to support the content. The presenter should expand on each point orally during the presentation. The word count for the provided outline is 285 words, therefore,additional content needs to be added to reach the required 1000 words.。
学术交流英语planning the presentation Planning the PresentationEffective academic communication is essential for sharing research findings, exchanging ideas, and fostering collaboration within the scientific community. Preparing a well-structured and engaging presentation is a crucial aspect of academic exchange. This article aims to provide a comprehensive guide on planning the presentation for successful academic discourse.Defining the Presentation ObjectivesBefore embarking on the presentation planning process, it is crucial to clearly define the objectives of the presentation. What is the primary purpose of the presentation Is it to introduce a new research project, present the findings of a study, or facilitate a discussion on a specific topic Identifying the key goals will help shape the content and structure of the presentation, ensuring that the audience receives the intended message.Knowing the AudienceUnderstanding the target audience is another crucial element in planning an effective presentation. Consider the composition of theaudience in terms of their academic background, level of expertise, and familiarity with the topic. This information will guide the depth and breadth of the content, the language used, and the overall tone of the presentation. Tailoring the presentation to the audience's needs and expectations will enhance the relevance and impact of the information shared.Conducting Research and Gathering ContentThorough research and careful curation of content are essential for a successful academic presentation. Gather relevant literature, data, and supporting materials that align with the presentation objectives. Critically evaluate the information to ensure accuracy, credibility, and relevance. Organize the content in a logical and coherent manner, prioritizing the most important and impactful points.Structuring the PresentationAn effectively structured presentation follows a clear and logical flow, guiding the audience through the key ideas and facilitating their understanding. Begin with an introduction that captures the audience's attention, provides an overview of the presentation, and outlines the main topics to be covered. The body of the presentation should present the content in a well-structured manner, with clear transitions between sections. Finally, conclude the presentation with a summary of the key takeaways and any relevant calls to action or future directions.Developing Visual AidsVisual aids, such as slides or multimedia components, can significantly enhance the effectiveness of an academic presentation. Carefully design these elements to complement the spoken content, rather than simply reading from the slides. Use visuals to illustrate complex concepts, highlight key data, or provide a visual representation of the research. Ensure that the visual aids are clear, concise, and easy to follow, avoiding excessive text or distracting animations.Practicing and Refining the PresentationThorough practice is essential for delivering a confident and polished academic presentation. Practice the presentation aloud, focusing on timing, flow, and delivery. Identify and address any areas that require further refinement, such as clarifying explanations, improving transitions, or enhancing the overall coherence of the presentation. Seek feedback from colleagues or mentors to gain valuable insights and make necessary adjustments.Engaging the AudienceEffective academic presentations foster active audience engagement, encouraging questions, comments, and discussions. Anticipate potential questions or areas of confusion and be prepared to address them. Encourage the audience to participate by incorporatinginteractive elements, such as polls, discussion prompts, or opportunities for Q&A. Maintain eye contact, use gestures, and adjust the pace and tone of the presentation to keep the audience engaged and attentive.Adaptability and FlexibilityAcademic presentations often occur in dynamic environments, where unexpected situations may arise. Develop the ability to adapt and remain flexible during the presentation. Be prepared to adjust the pace, content, or delivery in response to audience feedback or technical challenges. Maintaining composure and quickly addressing any issues will help ensure a successful and productive academic exchange.ConclusionPlanning an effective academic presentation requires a comprehensive approach that considers the presentation objectives, the target audience, the content, the structure, the visual aids, and the delivery. By carefully following these guidelines, researchers and scholars can enhance their academic communication skills, effectively share their work, and foster meaningful discussions within the scientific community. Mastering the art of presentation planning is a valuable asset for advancing knowledge and driving academic progress.。
销售部英文Sales DepartmentIntroduction:The sales department is responsible for generating revenue for a company by selling its products or services. It plays a critical role in the success of any business as it is responsible for meeting the sales targets and achieving the revenue goals. It is in direct contact with customers and clients and is responsible for building long-term relationships with them. In this paper, we will look at the key responsibilities of the sales department, the different roles in the sales team, and the skills required for a successful career in sales.Key Responsibilities:1. Developing a sales strategy: The sales department is responsible for developing a sales strategy that aligns with the company's overall business strategy. This includes identifying target markets, understanding customer needs, and developing a pricing strategy.2. Sales forecasting: The sales department is responsible for forecasting sales for the coming months or year. This helps the company plan its resources, set targets, and make informed business decisions.3. Lead generation: The sales department is responsible for generating leads through various channels such as advertising, social media, cold-calling,and networking. It is also responsible for qualifying leads to determine which ones are most likely to convert into customers.4. Sales presentations: The sales department is responsible for preparing and delivering sales presentations to potential customers. This includes understanding the customer's needs and tailoring the presentation to meet those needs.5. Negotiation: The sales department is responsible for negotiating with customers and closing deals. This includes understanding the customer's budget, persuading them to buy, and working out the terms of the sale.6. Customer relationship management: The sales department is responsible for building and maintaining long-term relationships with customers. This includes providing after-sales support, addressing customer complaints, and identifying further sales opportunities.Roles in the Sales Team:1. Sales manager: The sales manager is responsible for leading the sales team, setting targets, and ensuring that the team meets its goals. They are also responsible for coaching and mentoring team members.2. Sales representative: The sales representative is responsible for selling products or services to customers. They generate leads, qualify prospects, give presentations, negotiate deals, and provide after-sales support.3. Account manager: The account manager is responsible for managing relationships with key customers. They work closely with the sales representative and provide support as needed.4. Sales support: The sales support team is responsible for providing administrative support to the sales team. This includes managing customer databases, preparing sales reports, and coordinating sales activities.Skills Required for an Exciting Career in Sales:1. Communication Skills: Sales professionals must be skilled communicators who can build rapport and trust with customers.2. Sales Skills: Sales professionals must be able to generate leads, negotiate deals, and close sales.3. Time Management Skills: Sales professionals must be able to manage their time effectively to meet sales targets.4. Business Acumen: Sales professionals must have a good understanding of the company's products or services, target market, and competition.5. Emotional Intelligence: Sales professionals must have high emotional intelligence to read and understand the emotions of customers and colleagues.Conclusion:The sales department is a critical part of any business. It is responsible for generating revenue and building long-term relationships with customers. The success of the sales department depends on the skills and abilities of its team members. By focusing on sales skills, communication skills, business acumen, emotional intelligence, and time management skills, sales professionals can excel in their careers in sales.。
医务人员学术讲课取酬的工作提示英文回答:As a medical professional, it is common for us to be invited to give academic lectures and presentations. These opportunities not only allow us to share our knowledge and expertise with others, but they also provide us with a chance to earn some additional income. In this response, I will provide some tips on how medical professionals can effectively prepare for and deliver academic lectures and presentations, and how they can negotiate their compensation.Firstly, it is important to thoroughly prepare for the lecture or presentation. This includes conducting extensive research on the topic, organizing the content in a logical and coherent manner, and creating visually appealing slides or handouts. By doing so, we can ensure that our audience will be engaged and able to understand the information being presented.Additionally, it is crucial to consider the needs and expectations of the audience. For example, if we are presenting to a group of medical students, we may need to provide more detailed explanations and examples. On the other hand, if we are speaking to a group of experienced healthcare professionals, we may focus more on advanced concepts and research findings. By tailoring our content to the specific audience, we can enhance their learning experience and make the lecture more impactful.Furthermore, it is important to deliver the lecture in a confident and engaging manner. This can be achieved through effective public speaking techniques, such as maintaining eye contact with the audience, using appropriate gestures and body language, and speakingclearly and audibly. By doing so, we can capture the attention of the audience and ensure that our message is effectively conveyed.When it comes to negotiating the compensation for our academic lectures and presentations, it is important toconsider factors such as the time and effort required, the level of expertise and experience we bring to the table, and the financial resources of the institution or organization inviting us to speak. It is also important to be aware of the market rates for similar speaking engagements and to be prepared to negotiate if necessary.In conclusion, as medical professionals, we have the opportunity to share our knowledge and expertise through academic lectures and presentations. By thoroughly preparing for the lecture, tailoring the content to the audience, and delivering the presentation in a confident and engaging manner, we can ensure that our message is effectively conveyed. When negotiating our compensation, it is important to consider various factors and be prepared to negotiate if necessary.中文回答:作为医务人员,我们经常受邀进行学术讲座和演讲。
操作指南英文版Here is a 1000-word essay on the topic "Operating Manual (English Version)":Operating a complex machine or device can be a daunting task for many people unfamiliar with its inner workings and proper procedures. This is where a well-crafted operating manual becomes essential to ensure the safe and efficient use of the product. An operating manual serves as a comprehensive guide that provides step-by-step instructions, explanations of features and functions, and troubleshooting tips to assist users in getting the most out of their equipment.At the heart of a successful operating manual is clear and concise communication. The language used should be easy to understand, avoiding overly technical jargon that may confuse or intimidate the reader. The instructions should be presented in a logical and sequential manner, walking the user through the necessary steps to perform various operations. This includes detailed illustrations or diagrams to complement the written explanations, making it easier for the reader to visualize and follow along.One of the primary objectives of an operating manual is to ensure the safety of the user. By outlining the proper safety precautions and guidelines, the manual can help prevent accidents or injuries that may arise from improper use of the equipment. This includes highlighting any potential hazards, such as moving parts, electrical components, or high-temperature surfaces, and providing clear instructions on how to handle or interact with these elements safely.In addition to safety considerations, an effective operating manual should also address the maintenance and care of the device. Clearly explaining the recommended cleaning procedures, lubrication schedules, and replacement of consumable parts can help prolong the lifespan of the equipment and ensure its optimal performance over time. By empowering users with the knowledge to maintain their devices, the manual can contribute to a positive user experience and foster a sense of ownership and responsibility.Another crucial aspect of an operating manual is the troubleshooting section. This area should provide guidance on how to identify and resolve common issues that may arise during the use of the equipment. By offering step-by-step troubleshooting steps, accompanied by diagnostic information and potential solutions, the manual can help users address problems quickly and effectively, reducing downtime and frustration.The organization and layout of an operating manual are also important factors in its overall effectiveness. A well-structured manual should have a clear table of contents, allowing users to quickly navigate to the relevant sections they need. Additionally, the use of headings, subheadings, and bullet points can improve the readability and make the information more accessible to the reader.Furthermore, the operating manual should be designed with the user's needs in mind. This may involve considering factors such as the target audience's literacy level, preferred learning style, and cultural or linguistic differences. By tailoring the content and presentation to the specific needs of the users, the manual can enhance its overall effectiveness and improve the user's experience with the product.In conclusion, a comprehensive and well-written operating manual is an essential component of any complex machine or device. By providing clear and concise instructions, addressing safety concerns, offering maintenance guidance, and incorporating troubleshooting support, the manual can empower users to operate their equipment with confidence and efficiency. Ultimately, a well-designed operating manual can contribute to the overall success and satisfaction of the product, making it a valuable investment for both the manufacturer and the end-user.。
Tailoring the Presentation of Plans to Users’ Knowledge and CapabilitiesDetlef KüpperDept. of Mathematics and Computer ScienceUniversity of EssenD-45117 Essen, Germany+49 7732 54872Detlef.Kuepper@epost.deAlfred KobsaDept. of Information and Computer Science University of CaliforniaIrvine, CA 92697-3425, U.S.A.+1 949 824-3007kobsa@ABSTRACTTailoring advice to a user means finding a plan by which she can reach her goal, and supplying the missing knowl-edge that she needs to successfully execute the plan. The paper presents an algorithm to determine the kind and amount of this missing knowledge for an already generated domain plan. We show that both the user's knowledge and his capabilities to perform actions must be taken into account when deciding on a plan presentation that is ade-quate for him. We also demonstrate that it may be useful to consider issues of plan presentation already during the planning process, and indicate how this can be accom-plished in a planning system.KeywordsUser-tailored advice, plan presentation, user modeling INTRODUCTIONThe effectiveness of advice-giving systems essentially hinges on users’ ability to take advantage of the given advice to reach their goals. The problem of whether a user can understand an advice already received considerable attention in the research literature (see, e.g. [22] for a sur-vey). However, an additional prerequisite for the success of advice is that the user must be able to execute the advice, i.e. have the capabilities to perform each step of the advice. Capability in this sense means the user’s personal abilities and her authorization to perform the actions that occur in the advice.In [11], we proposed a plan generation approach to achieve the user’s goals that considers the user’s capabili-ties. The resulting plans are therefore in principle executa-ble by the user. In order to perform the plan, she may however still need additional information. This possibly missing knowledge – or in general the gap between a user’s capabilities to perform plans and his knowledge how to do this – determines the scope of user-tailored advice. In this paper, we describe our approach to identify the knowledge that the current user still needs to perform a plan. We start with a plan that the user can in principle execute and that is suitable for reaching the user’s goals. We will show that the knowledge that is still required depends not only on the user’s knowledge but also her capabilities.The rest of the paper is organized as follows. First, we summarize central characteristics of the user model that we employ and introduce some terminology. The next section discusses the different types of knowledge that users need in order to perform a plan. We then present an algorithm that determines such knowledge for an already generated plan specifically for the current user. This algo-rithm also determines the “presentation cost” of the knowledge/plan to be communicated, which is propor-tional to the structural complexity of the presentation and can be regarded as a coarse estimate of the user’s compre-hension efforts. Afterwards, we re-integrate our results into the plan generation process to ascertain that plans will preferably be generated that the user is not only capable of performing, but that also have the lowest presentation costs. We also discuss other measures besides presentation cost for rating plan presentations that take user skills, user preferences, and the likelihood of success into account. Finally we describe some related research, and outline future work to decide which parts of the missing knowl-edge identified by our algorithm should be presented explicitly and which parts may omitted, depending on (assumed) inferences that the user may draw. ELEMENTS OF OUR APPROACHOur approach exploits an extension of the user model that was presented in [11]. This model separates the system’s assumptions about the user’s knowledge from its assump-tions about his capabilities. Capabilities of a user are mod-eled a s plan operators that the user is in principle able and authorized to execute. These plan operators have a termi-nological representation in the user model, the so-called plan concepts. Preconditions and effects of plan operators are represented by attributes of their plan concepts. For the generation of user-tailored plans, plan operators/concepts can be instantiated and become the steps of the plans.Submitted to the 2002 Conference on Intelligent User Interfaces, San Francisco, CAAdditionally, the plan concepts are also used for modeling (the system’s assumptions about) the user’s planning knowledge, and the system’s own planning knowledge. Because plan steps are instances of plan concepts, assump-tions about the user’s knowledge about plan steps are inherited from the assumptions about his knowledge about plan concepts. The same holds true for the user’s capabili-ties.For reasons of simplicity, we will not stringently distin-guish between plan concepts/operators and plan steps in the remainder of this paper. Note however, that plans always contain plan steps, each of which inherits its prop-erties from the plan concept of which it is an instantiation. Expressions like the user knows a plan step and the user can perform a plan step should also be read in this sense as meaning that the user knows / can perform the plan concept step of which the plan step is an instantiation.We already mentioned that the plan to be presented to the user was generated in consideration of the user's capabili-ties. While the exact nature of the planning process is irrelevant for presentation purposes (we use UCPOP [15], as described in [11]), we require that the plan to be pre-sented not only contains steps but also so-called causal links, which are by-products of the planning process. A causal link (s, l, r) is a relation between a plan step s, a condition represented by literal l1 that is satisfied by s, and a step r that requires s for its executability2. We need causal links to provide information about the structure of the plan (see below).DETERMINING THE CONTENTS FOR PLAN PRESEN-TATIONThe goal of plan presentation is to enable the user (or in general, the recipient of the presentation) to perform the plan in order to reach his goals. Our approach is guided by the idea that a plan for a user should not be decomposed to the lowest possible level (e.g., down to the level of finger movements) since the efforts for communicating and com-prehending such plans are very high. Rather, plan presen-tation should rely on users’ ability to further elaborate the communicated plan.3 Such a plan still includes, e.g., abstract plan concepts that need to be refined, and abstract object descriptions that need to be replaced by identified objects. When such a plan becomes presented to the user, he is expected to continue decomposing plan steps into a sequence of more primitive executable actions (which may even be well beyond the system’s domain model). If unex-pected obstacles hinder a successful execution of such a 1Like many other planning systems, we assume that precondi-tions, effects and the goal are conjunctions of first order literals.2r may also represent the plan’s final goal. In this special case, l is part of the goal condition.3Cf. [24], who considered plans as starting points for further elaboration rather than a fixed recipe of what to do.more abstract plan, the user also still has an opportunity to modify it.Thus, the contents of a plan description cannot be regarded as a homogeneous piece of information. Besides simply listing the plan steps in a correct sequence, the user needs knowledge about the properties of and interrelations between the plan steps, and she must know how to perform the steps of the plan. Furthermore, she may require refer-ential descriptions and properties of objects that play a role in the plan (but we will not deal with this issue because of the rich research experience that is already available, like e.g., [9], [20], [19]).Knowing Plan Steps and Their InterrelationsThe simplest way to communicate a plan is to enumerate its steps in a suitable order. According to [5], [6], users usually want to know the reason why each individual step is in the plan, i.e., what part they play for reaching the plan’s goal. This information is provided by the causal links of the plan. Each of them describes which step satis-fies which condition for which other step. Thereby, causal links provide knowledge about the preconditions and effects of the plan steps that are relevant in this plan. Additionally, the knowledge represented in causal links is useful for modifying the plan when unexpected obstacles are detected. Such a modification is a continuation or a partial revision of the planning process. Although we do not expect the user to plan in the same way as an AI plan-ning system, he must take the same elements into account if he is to continue or correct a plan. Specifically, he must know the properties of the plan steps, namely their precon-ditions and effects, and the causal links between plan steps. Knowledge about these relations is particularly important, because each modification of the plan must take care not to threaten a causal link. This means that if a plan contains a causal link (s, l, r), no modification between step s and step r is allowed that negates l because other-wise the precondition of step r is not satisfied anymore and thus the plan will fail (see below for an example).Fig.1 is an example of how a user – similar to a planning system – must take care not to threaten causal links by effects of additional steps. The figure shows part of a sim-plified plan that achieves the goal of obtaining a printout of a file on a remote host. Disregarding some details, the plan fragment in Fig. 1 specifies that users can reach this goal by getting the file into their local file systems (e.g. by FTPing it – as shown in Fig. 1, or by mounting a foreign directory, depending on their permissions) and then printing it in a text processor. Both applications must be launched before they can be used. An execution of the steps from left to right is compatible with the temporal constraints imposed by the causal links. Suppose that the FTP program is not in the foreground of the desktop immediately before step ftp-bin-mode, and that the user wants to redress this obstacle. Although one possibility is to kill all other active applications, this approach is in-appropriate because it threatens the causal link between launching the text processor and opening the document file. Only if the user is aware of the causal link can she detect this threat and choose an alternative.In summary, knowledge of the plan’s causal links provides a teleological explanation for the presence of each step in the overall plan and supports an elaboration of the plan by the user. This knowledge, together with the sequence of the plan steps, constitute the knowledge of the plan struc-ture that a user should possess to be able to successfully execute a plan.Knowing How to Perform a Step of a PlanIf we generate a plan for an unintelligent robot, we must plan down to the level of the instantiated commands of the robot’s functional interface, which the robot can execute directly. If we plan for humans though, it makes no sense to refine plans to the level of actions that can be executed directly, like moving one’s arm or fingers. This would cause an enormous increase in the domain modeling effort, planning complexity, communication effort, and in the user’s memory load, and would also result in a low user acceptance of the (necessarily lengthy) advice. Instead, we want to exploit users’ ability to decompose complex plan steps. However, the user may need additional advice for this task if his knowledge is insufficient or even wrong. This brings us to the problem of whether and, if so, what additional advice is useful for the current user on account of a user model. To provide such advice, the system’s domain model and possibly its user model must include knowledge about how to perform plan concepts. To this effect, each plan concept can be associated with one or more decompositions of the plan concept in the models of the system’s and the user’s knowledge. Such decomposi-tions are sets of partially ordered plan steps and thus (simplified) plans. Steps of decompositions are – similar to steps of plans that are generated by the planning system –instantiations of plan concepts. This is roughly comparable to the decompositions of hierarchical planning (see, e.g., [18], [3]). However, we use a simplified approach. Plan concepts that are used in decompositions usually do not possess preconditions and effects. Thus they cannot be used for planning any more. Rather, we use decompo-sitions as canned recipes of how to perform the plan con-cept that is associated with the decomposition. This is justified because we require that the plan generation proc-ess that precedes plan presentation (described in [11]) already considered all relevant conditions and dependen-cies.A plan concept is marked as atomic in the user model if the user does not need further information about it (such plan concepts may be directly executable, or the user may have extensive competence for further plan decomposition that goes beyond the system’s domain model). For a non-atomic plan concept, the decision on what to explain to the user will be made based on the user’s presumed knowledge about how to perform the plan concept. We already dis-cussed that such knowledge is represented by one or more decompositions of the plan concept. But even if the user has such knowledge, it may be wrong, or not usable since the user is unable to perform it. A decision against further explanations is only made if the user’s knowledge about how to perform the plan concept is assumed to be reliable. We call a plan concept reliable ifa) none of the decompositions of the plan concept iswrong andb) at least one is usable single-handedly by the user. The former should prevent the user from considering wrong execution alternatives. The reference point for judging correctness is the system’s domain model: a de-composition of a plan concept in the model of the user’s knowledge is correct iff it is also part of the system’s knowledge. A decomposition is usable single-handedly (by the current user)if the user can in principle perform all its steps and has reliable knowledge about how to perform these steps if they are non-atomic. Note that the steps of a decomposition – similar to the steps of the generated plan – may be instantiations of non-atomic plan concepts, and that the agent who executes them must therefore know how to perform them.4 Assumptions about user miscon-ceptions regarding how to perform plan concepts may stem from knowledge about typical errors of user groups, or from the recognition of individual user misconceptions (e.g., [17]).4We do however not expect the decomposition hierarchy to be very deep. In our example domain, the steps of a decomposi-tion usually correspond directly to atomic plan concepts.Fig. 1.Simplified plan fragment for goal obtain a printout of a file on a foreign host. Plan steps are shown as rectangles, arcs labeled with a literal denote causal links.For plan concepts that require further explanations of how the user can perform them, the system must select one of the decompositions of this plan concept from its own knowledge. However, the different decompositions gener-ally do not lead to equally good explanations (more on this in the next subsection), and some of them may not even be usable by the current user. A decomposition is usable (by the current user) if the user can perform all its steps in principle and for each non-atomic step, the system knows at least one decomposition that is usable by the current user.For an example of a decomposition that is unusable, con-sider the plan concept shutdown-windows-computer with the following two decompositions: (1) push keys <Ctrl>, <Alt>, <Del> simultaneously, then choose <shutdown-button>, and (2) choose <Start> from the task bar, then choose <Shutdown>. Although both recipes will shut down a computer under Windows, the first one will be unusable for a user who cannot push three keys simultaneously.If the system knows more than one usable decomposition of a plan concept, it should select the "best" one. The fol-lowing presentation algorithm therefore computes a valua-tion of each alternative. The rating of a plan concept depends on the rating of the components of the decomposi-tion and – if the decomposition contains plan concepts that require further explanations – the valuation of decomposi-tions that will be used for these explanations.The Presentation AlgorithmThe pseudo code of Fig. 2 summarizes the procedure for determining the knowledge that the user needs to success-fully execute a plan p. The task is distributed among three functions which return two values, namely a data structure that represents the contents of the presentation, and a numerical value that represents the rating of this presenta-tion. We call the latter presentation-cost and use the auxil-iary functions presentation and cost to access these two results.The function present-plan processes a plan, which sub-sumes generated plans as well as decompositions of plan concepts. It starts with a linearization5 of the plan (p2) and adds the name of the corresponding plan concept for each plan step (p3). This should enable the user to identify the steps. Function present-plan-concept determines if and what information on plan concepts the user needs. The function is called for each plan concept unless it had al-ready been processed6. An explanation of a plan concept may consist of a canned description if the user does not know the concept (c2,c3), and user-specific information about how to perform it if the plan concept is non-atomic and the user does not have reliable knowledge (c4,c5). User-specific information about how to perform a plan 5The plan generation process may result in a plan that is only partially ordered.6The bookkeeping parameter cs will be described below.present-plan (p:plan, cs:set-of-plan-concepts)(p1) set cost initially to ( | steps (p) | + 2 * | causal-links (p) | ) * k pres(p2) set presentation initially to linearize(p)(p3) for each s∈steps (p) add the name of plan-concept(s) to s in presentation(p4) for each pc∈plan-concepts (p) \ cs(p5)add results of present-plan-concept(pc, cs) to presentation, cost(p6)add pc and all plan-concepts of presentation (present-plan-concept(pc, cs)) to cs present-plan-concept (pc:plan-concept, cs:set-of-plan-concepts)(c1) set presentation initially to {}; set cost initially to 0(c2) if user doesn’t know pc(c3) set presentation to descript(pc) and cost to cost(descript(pc))(c4) if not (pc is atomic or user has reliable knowledge of pc)(c5)add results of present-recipe-for-plan-concept(pc, cs) to presentation, cost present-recipe-for-plan-concept (pc:plan-concept, cs:set-of-plan-concepts)(r1) let ec be the set of usable decompositions of pc according to system’s knowledge(r2) if ec = {} → set cost to ∞ (plan presentation fails)(r3) else set presentation, cost to results of present-plan (d, cs) where(r4)d∈ec∧cost(present-plan(d, cs)) = min(d’∈ec)cost(present-plan(d’, cs))Fig. 2. Pseudo code of the plan presentation algorithmconcept is determined by the function present-recipe-for-plan-concept. It selects the decomposition with the mini-mal cost (r4) from the set of usable decompositions of the plan concept (r1). The presentations of these decompo-sitions are computed by the function present-plan. The depth of these recursive calls is limited by the depth of the decomposition hierarchy of the plan concepts. Line (r2) handles the case in which the system cannot give an explanation that is usable by the current user. The subse-quent enhanced plan generation process excludes such un-explainable plan concepts from further consideration and thus produces plans only for which the algorithm can come up with an adequate presentation.Let us now discuss some more details of the presentation algorithm. We use the auxiliary functions steps, causal-links and plan-concepts which return the set of steps, causal-links and. plan concepts of a plan. The function plan-concept of a plan step yields the plan concept of which the step is an instantiation.To avoid multiple explanations of the same concept, the loop beginning at line (p4) excludes plan concepts that are in cs, the set of already processed plan concepts. This set is passed on to all subsequent function calls as their second argument. Since an explanation of a plan concept may contain explanations of other plan concepts that are also used later in the plan, the set is updated after each call of present-plan-concept (p6).Besides it’s main task – determining the missing knowl-edge that the user needs for successful plan execution – the algorithm computes a value called presentation-cost. Each component of the presentation contributes to this value: steps and causal links in line (p1), and descriptions of plan concepts in line (c3). If we follow the propositional theory of text comprehension [7], [8], this may be seen as a rough estimation of the user’s effort to comprehend the presenta-tion, because all components carry new information that must be processed by the user if they are presented explic-itly. In (p1) we use the factor k pres as a unit for the pres-entation cost. If we use it to estimate the user’s compre-hension effort, k pres stands for the effort that is caused by the presentation of one plan step. Since causal links are more complex components, each contributes two units to the presentation cost.An ExampleIn the following, we would like to demonstrate the opera-tion of our algorithm for different system assumptions about the user’s knowledge. We choose the presentation of the step ftp-dnload-bin in Fig. 1 as an example. Fig. 3 shows three possible decompositions of this plan concept:1 select-file-menu-item and push-2key (Alt, O)2 select-file-menu-item, click-button (download) andclick-button (transfer)3 select-file-menu-item and push-2key (Alt, T)In this example, users download files in the FTP program by first selecting the file and then initiating the transfer. The latter may be done by either pushing the key combina-tion <Alt>-<O>, or by first clicking a button for the copy direction and then the transfer button. These two alterna-tives are modeled by decompositions 1 and 2, respectively, both of which are included in the system’s domain model (see Figure 3). A frequent error is the mix-up of <Alt>-<O> with <Alt>-<T>. The corresponding decom-position 3 is not included in the system's domain model, which means that it is regarded as incorrect by the system. Assume that a user A knows decomposition 2, is able to perform all its steps, and that all steps are atomic for him.Fig. 3. Different planning knowledge of system, and two usersThe respective plan concepts are therefore contained both in the knowledge and the capabilities part of A’s user model7, and marked as atomic in the knowledge part. User A therefore has reliable knowledge about ftp-dnload-bin and does not need further explanations thereon. Function present-plan-concept in line (p5) of Fig. 2 yields an empty presentation, and 0 for the presentation-cost.Assume that user B believes that ftp-dnload-bin can be decomposed into decompositions 2 and 3. Both are there-fore contained in the knowledge part of B’s user model. From the system’s point of view, B believes in both correct and incorrect decompositions. Since her beliefs about ftp-dnload-bin are hence not reliable, the system must provide its own decomposition. To this end, function present-plan-concept calls present-recipe-for-plan-concept (c5), which must decide between the presentation of decompositions 1 or 2. If B is able to perform all steps of either decomposi-tion and if all are atomic, both decompositions are usable. The decision between them in (r3,r4) is made by applying present-plan to both alternatives and opting for the one with the lower returned presentation costs. In (p1-p3), a presentation is constructed consisting of two steps for decomposition 1 and three steps for decomposition 2, respectively. The costs are determined as 2 * k pres and 3 * k pres, (lines (p4-p6) add no extra costs since all plan steps are atomic), and decomposition 1 is thus preferred in (r3,r4).If user B would not know how to perform push-2key (Alt, O), then present-plan-concept (p5) would generate a decomposition of this concept as well (via recursive calls of present-recipe-for-plan-concept and present-plan), and add its costs to 2 * k pres. The total presentation-cost of decomposition 2 will be lower in this case. Decomposition 2 will also be selected if the user is not able to perform push-2key (Alt, O) (say, since these keys are relatively far apart). In this case, decomposition 1 would not be in the set of usable decompositions and therefore not be consid-ered any further.CONSIDERING PLAN VALUATION DURING PLAN GENERATIONUp to here our discussion separated the two phases of user-tailored advice. This is beneficial for obtaining a clearer picture of the processes and knowledge sources that sup-port the different aspects of plan generation and plan pres-entation. A generation process that completely disregards the need for subsequent plan presentation may however end up with a plan that requires tedious explanations, or in the worst case does not have an acceptable presentation at all.We can identify two starting points for considering pres-entation aspects during plan generation without curtailing the solution space of the presentation component. First, we7 See [11] for a more detailed description of the formalisms used for plan and user model representation exclude unexplainable non-atomic plan concepts from the planning process, because their occurrence in a plan always leads to a rejection of the presentation. The second onset exploits a planning control feature in UCPOP [15], the planning system that we use. Gerevini and Schubert [4] investigate several search control strategies to speed up the planning process. We use some of their results to bias the planning process to prefer "good" plans, i.e. plans for which the presentation algorithm will compute a low pres-entation-cost. The UCPOP algorithm works on several plan candidates in parallel. Before each step, it rates all candidates and chooses the candidate with the best rating to work on next. We use a rating function that considers the presentation-cost of the plan candidate. Thus UCPOP will work first on the plan candidate with the lowest pres-entation-cost and eventually find a solution. If UCPOP adds steps or causal links to the plan candidate, the presen-tation-cost of this candidate increases and UCPOP may work on another candidate in the next step if it has a better rating. Thus, the first solution found has the lowest pres-entation-cost. This means that plans with a low presenta-tion-cost are preferred, but no solution is lost.For efficiency reasons we do not use the function present-plan to calculate the presentation-cost. Instead, we com-pute the direct presentation-cost and the explanation set of each plan concept before the planning process starts. The direct presentation-cost of a plan concept is determined by the cost of its description if the user does not know the concept, and the number of (direct) steps of an explanation if the user does not know how to perform it. The explana-tion set of a plan concept is the set of plan concepts that would be used (indirectly) in an explanation of how to perform the plan concept if the user would need such an explanation, and the empty set otherwise. Thus the rating of a plan candidate p can be computed as the sum ofa) ( | steps(p) | + 2 * | causal-links8(p) | ) * k pres plusb) the direct presentation-cost for each plan conceptpc∈ (plan-concepts(p)∪pc'∈plan-concepts(p)explanation-set(pc')) .This value is a fairly close approximation of the value that would be computed by a function present-plan. However, the plan concepts that are used for a plan in the presenta-tion algorithm may influence the decision between alterna-tive explanations of plan concepts that are used later in the plan. This may result in a lower presentation-cost than the value computed for the plan candidate.While we exploit this technique of biasing the planning process in the way described only, we also see three other promising application purposes:8Remember that only the generated plan may contain causal-links.。