Table 1 shows the statistics based on all questions answered,... some students answered four questions. Averages are fairly consistent across
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Table 1 shows the statistics based on all questions answered,... some students answered four questions. Averages are fairly consistent across
BCS THE CHARTERED INSTITUTE FOR IT BCS HIGHER EDUCATION QUALIFICATIONS BCS Level 6 Professional Graduate Diploma in IT MARCH 2014 EXAMINERS’ REPORT KNOWLEDGE BASED SYSTEMS General Table 1 shows the statistics based on all questions answered, including where some students answered four questions. Averages are fairly consistent across questions 1,2,3,5, though, a little on the low side. Q4 seems to be the best answered. Standard deviation results are fairly low across all questions. Thus, it may be concluded that the candidates appear to be fairly equated in their ability, but perhaps were overly challenged by the examination (as was the case in the previous years). However, the spread of results (range) is wide which would indicate that there were some high achieving candidates. The statistics are very much in line with previous years. It was expected that Question 2 would challenge candidates the most since it covers relatively new issues for this course (sustainability and green IT), and although it produced the lowest average mark, results were on comparative levels of performance with most of the other questions. Question 4 was anticipated to attract the best performance since it has appeared on previous exam papers, and indeed, it was the best attempted. In general, candidates seem not to have prepared well for the paper, and have taken an instrumental approach in which they have revised previous exam questions and attempted to recreate the answers verbatim. Where variations in questions have been included, or new questions are presented, candidates have struggled. Table I 1 1. There is a growing concern today about sustainable systems and green IT as these issues can affect the choice of systems built and manner in which they are operated and managed. i. Develop an argument either in favour of or against the preference for KBS over conventional IT systems. The discussion must be justified by appeal to sustainability principles and green IT issues. (15 marks) ii. Discuss the broad implications for KBS arising from the introduction of cloud computing techniques that provide intelligent computing power over the Internet. (10 marks) MODEL ANSWER POINTERS Question 1.i: 15 marks. General distribution of marks according to salient features. Candidates must demonstrate an appreciation of sustainability and green IT issues and show the impact that these issues have on KBS and intelligent systems. Learning Outcomes/Assessment Criteria: 2. The learner will be able to critically compare and contrast various knowledge representation systems. [2.1, 2.2, 2.3, 2.4, 2.5] 3. The learner will understand methodological approaches to developing knowledge based systems. [3.1, 3.2, 3.3, 3.4] 4. The learner will understand concepts and appreciate the significance of issues relevant to adaptive computing. [4.1, 4.2, 4.3, 4.4] 7. The learner will know how AI technology has been used in real situations particularly on the Internet.[7.3, 7.4] Indicative solution There are many perspectives that can be taken, for instance, issues regarding the comparative amount of resources needed to develop KBS and the need to maintain/update systems will draw on sustainability issues. Also, higher levels of labour involved in the development need to be balanced with lower levels of labour required for subsequent use. Autonomy, where the autonomous nature of embedded KBS systems over the operator-dependent design of conventional systems saves resources. Similarly, with Reusability in the context of software components (rule base/object oriented). Efficiency through better usability (e.g. intelligent interfaces) reduces operating time and energy usage, Flexibility, where for instance agile approaches may be seen to be more sustainable for re-design and maintenance than overly rigid and intensive development methods in some cases, etc. 2 Question 1.ii: 10 marks. General distribution of marks according to salient features. Candidates must demonstrate an appreciation of cloud computing concepts and show the potential for this technology to support KBS and intelligent systems usage. Learning Outcomes/Assessment Criteria: 3. The learner will understand methodological approaches to developing knowledge based systems. [3.3, 3.4] 4. The learner will understand concepts and appreciate the significance of issues relevant to adaptive computing. [4.1, 4.2, 4.3, 4.4] 6. The learner will know the major AI application areas and understand the AI techniques used within them. [6.1, 6.2, 6.3, 6.5, 6.6, 6.7] 7. The learner will know how AI technology has been used in real situations particularly on the Internet. [7.1, 7.2, 7.3, 7.4] Indicative solution This is a relatively new area so candidates will need to rely on general knowledge of KBS and the IT industry if they have not studied the topic. Sustainability issues - a paramount concern as without the need to develop personal copies of software a large positive environmental impact can be produced. Applicability issues - relating to the relevance of generic KBS to specific company related tasks need to be addressed. Generality issues relating to how the knowledge in a KBS can be represented in general forms so as to be usable by different organisations. Robustness issues - greater usage places more strain on the limits of a KBS. Maintenance issues particularly with CBR approaches may be enhanced with the wider coverage that comes from a larger user base (over the internet). Confidentiality associated with company and task sensitivity. Etc. EXAMINER’S COMMENTS A1.i a) Answers confused the sustainability issues involved in the development and use of KBS systems (such as more efficient algorithms leading to reduced computing resources), with applications built from KBS that may be used to achieve sustainability goals (such as fuzzy controllers for heating). b) Answers presented appropriate sustainability issues but did not provide adequate discussion to support the main ideas. c) Answers covered general principles of sustainability and Green IT without linking to KBS. 3 A1.ii a) Main issues of cloud computing for KBS were identified but not discussed adequately. Mostly single sentence explanation accompanied each issue. b) Answers discussed general principles of cloud computing without linking to KBS. 2. Consider a multi-agent based system (MAS) for an application of your own choice (real or hypothetical): i. Specify the nature of the task facing the multi-agent system and justify why it requires a solution reliant on decentralisation and distribution of responsibilities. (10 marks) ii. Explain the differences between cooperative and competitive MAS and discuss which is most appropriate for the example. (15 marks) MODEL ANSWER POINTERS Question 2.i: 10 marks. General distribution of marks according to salient features. Candidates must demonstrate an appreciation of how MAS function. Learning Outcomes/Assessment Criteria: 1. The learner will understand the main approaches used in AI problem solving. [1.1, 1.2] 5. The learner will know methods used in adaptive computing and understand how to apply them to problem solving.[5.1, 5.2] 6. The learner will know the major AI application areas and understand the AI techniques used within them. [6.1, 6.2,6.3, 6.4, 6.5, 6.6, 6.7] 7. The learner will know how AI technology has been used in real situations particularly on the Internet.[7.2] Indicative solution Any task may be chosen and answers should focus on the need to distribute intelligence due to the complexity of the task. Explanations must demonstrate that multiple agents are necessary for solution generation. 4 Question 2.ii: 15 marks. Five marks for each according to salient features. Five marks for justification. Candidates must demonstrate an appreciation of how MAS function. Learning Outcomes/Assessment Criteria: 1. The learner will understand the main approaches used in AI problem solving.[1.1, 1.2, 1.3] 4. The learner will understand concepts and appreciate the significance of issues relevant to adaptive computing. [4.1, 4.2, 4.3, 4.4] 5. The learner will know methods used in adaptive computing and understand how to apply them to problem solving. [5.1, 5.2, 5.3, 5.4, 5.5] 6. The learner will know the major AI application areas and understand the AI techniques used within them. [6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7] Indicative solution Cooperative: agents work towards shared goals (all win or all loose). Competitive: agents work towards different goals in an environment of limited resources (some win and some loose). Answers should explain these concepts in detail and provide justification for the choice of the most appropriate one for the chosen task. EXAMINER’S COMMENTS A2.i a) Although general characteristics of MAS were presented, answers failed to present detailed description of the example application and did not include justification of the need for decentralisation and distribution. b) Answers often showed confusion over meaning of competitive MAS – these are within the same application but compete for resources to achieve subgoals of the same task NOT two separate applications vying to win over the other. A2.ii a) Justification for choice of competitive or cooperative not given in detail but just stated. Full rationale is expected. 3. Data Mining has been capitalised on in the commercial world through the implementation of Business Intelligence Systems. i. Discuss how Data Mining technologies have made the transition from research laboratory to business applications. Focus on the real business problems that data mining technologies address and the benefits perceived to have been realised. (15 marks) ii. Discuss the implications of using intelligent data analytics to unfairly exploit data on user behaviour. (10 marks) 5 MODEL ANSWER POINTERS Question 3.i: 15 marks. General distribution of marks according to salient features. Candidates must demonstrate an appreciation of commercial usage of data mining technology, and how application tools have been developed for use by the non-technical business user. Learning Outcomes/Assessment Criteria: 1. The learner will understand the main approaches used in AI problem solving. [1.2] 4. The learner will understand concepts and appreciate the significance of issues relevant to adaptive computing. [4.1, 4.3, 4.4] 6. The learner will know the major AI application areas and understand the AI techniques used within them. [6.1, 6.2, 6.3, 6.4, 6.6, 6.7] 7. The learner will know how AI technology has been used in real situations particularly on the Internet. [7.1, 7.2, 7.3,7.4] Indicative solution Data mining is often used in business, particularly on the web, to provide support for the “implicit web,” in which personal information about the user is indirectly “discovered” from their normal interactions. Such valuable knowledge enables tailoring and personalization of services. With the increased power of Web 2.0, in which users are generators of data and not just consumers, many new opportunities have emerged for technologies that can make value of the available data. Data mining as employed in business intelligence systems and data analytics are means by which Strategic management is implemented. The knowledge derived from analysis of data using data mining helps a decision maker understand the nature of the problem better and supports better informed decision making. Data Mining can support the tactical detail about exactly how a strategy will translate to actions. In the business world, data mining is used extensively for personalized marketing, e.g. for profiling users and targeting advertisements to their interests and needs. 6 Question 3.ii: 10 marks. General distribution of marks according to salient features. Candidates must demonstrate current awareness of an important application of artificial intelligence technology, data mining, and comment on its potential dangers in the context of privacy. Learning Outcomes/Assessment Criteria: 1. The learner will understand the main approaches used in AI problem solving. [1.1, 1.2] 5. The learner will know methods used in adaptive computing and understand how to apply them to problem solving. [5.1, 5.2, 5.3, 5.4, 5.5] 6. The learner will know the major AI application areas and understand the AI techniques used within them. [6.1, 6.2, 6.3, 6.4, 6.5] 7. The learner will know how AI technology has been used in real situations particularly on the Internet. [7.1, 7.2, 7.3, 7.4] Indicative solution Data mining is now used in intelligent search engines on the web (Google), games, consumer robots with vision systems, handwriting reading in PDA, speech synthesis in word processors, intelligent tutoring, knowledge management, etc. As knowledge working grows, it is expected that such technologies would continue to become more prevalent and the potential for abuse of privacy thus grows. A major factor impacting on the spread of data analytics is concerns with the manner in which data are collected, interpreted, distributed and manipulated to achieve a competitive advantage. The limits of what is acceptable to the consumer can often be pushed by companies seeking to capitalize on the value of data. As an example, employers these days can and do survey personal data on social network sites, such as Facebook, to glean background data on prospective employees. Answers could describe how monitoring of pages visited (times and location) can be used to develop a profile of users’ interests without their explicit consent to that information, which could be potentially sold on, or used to target marketing campaigns. Answers must consider realistic and timely reasons, e.g. right now technological growth in terms of mobile systems enables data to be stored on location, which can be interpreted to the advantage of marketers. 7 EXAMINER’S COMMENTS A3.i a) Descriptions of data mining approaches were provided but there was a lack of explanation on evolution from lab to business, e.g. due to eBusiness, internet, cloud, big data. b) Although examples were given of how data mining has been used, these were without discussion of the facilitating factors (i.e. big data, cloud, internet, eBusiness). A3.ii a) Although issues about privacy are mentioned in answers, details are lacking about the consequences of unethical use of data. 4. Knowledge based Systems (KBS) are developed to deal with particular application domains in which elements of human intelligence are essential in producing solutions. i. Identify and discuss five aspects of human intelligence that could be used to characterise intelligent knowledge-based systems. (15 marks) ii. Take one aspect of human intelligence and explain how it would be difficult to emulate using rule based systems. (10 marks) MODEL ANSWER POINTERS Question 4.i: 15 marks. 3 marks for each aspect of human intelligence identified and related to KBS. Some possibilities include: Ability to temporarily alter behaviour according to environmental stimulus (adaptability) Ability to permanently alter behaviour as a result of accumulated experience with environmental stimuli (learning) Ability to deal with ill-defined and ambiguous situations (uncertainty) Ability to prioritise and focus (goal directedness) Ability to bring to bear subjective insight (judgement) Ability to deal with complexity and recognise relevance (abstraction) Application of these traits to a medical diagnostic KBS should consider the points outlined below. Adaptability: an investigative procedure can be refined as new symptoms emerge and new test results become available. Abstraction: the most significant symptoms will be considered, and those may be considered as special cases of more general categories of symptoms. 8 Connections between symptoms and causes may be established at the general level, e.g. fever is one of the flu-like symptoms, and flu-like symptoms could point to influenza, pneumonia, viral infection, etc. Goal directedness: the diagnostic system has a main goal: to identify the cause of the symptoms; and will plan procedures that progress towards achieving that goal. Judgement: recommendations and decisions will be based on experience with previous patient cases; thus, different experts may have different judgement (c.f. second opinion). Learning: procedures for selecting and conducting tests are based on treatment of previous patients (with similar symptoms). Results of the treatment fed back to the KBS will be used to influence future decisions. Uncertainty: prognoses about illnesses are often predictions that are based on incomplete information about the progression of the illness in the patient. That is, there can be incomplete information about the disease and about the patient. Question 4.ii: 10 marks. General distribution of marks according to salient features. Some possibilities include: Creativity and imagination are currently not well understood, and are thus, difficult to describe in an executable computer model. An ability to recognise faces and differentiate between male and female faces is another area where clear rules are difficult to elicit because the relevant knowledge is not easily brought to conscious attention. In general, activities that could be better described as skills (opposed to knowledge) are not amenable to knowledge based systems. EXAMINER’S COMMENTS A4.i a) Answers introduced aspects of intelligence but (i) did not provide an example from humans and/or (ii) did not apply them to KBS. Instead answers often just gave superficial descriptions of each aspect in humans or just mentioned that “it applies to KBS too.” b) Some answers failed to identify appropriate aspects of human intelligence that set apart KBS from conventional systems, e.g. “being able to solve a problem.” A4.ii a) Answers mostly identified creativity as being hard to emulate in KBS, but restricted definition to “producing something new”. KBS can discover knowledge, but the processes employed by humans and machines are different. KBS cannot be artistic in creating new things. 9 b) Many answers stated two or three tasks difficult for RBS (creativity, skills, face recognition) but failed to discuss any in depth. The question asked for 1 task to be discussed with supporting explanation. 5. Using examples to illustrate your answers, explain the differences between the following concepts: i. procedural and declarative knowledge. (10 marks) ii. data driven and goal driven reasoning methods. (10 marks) iii. abductive reasoning (5 marks) MODEL ANSWER POINTERS Question 5: 25 marks. five marks for definition of each concept. Candidates must demonstrate knowledge of fundamental concepts and be able to distinguish similar or competing elements. Learning Outcomes/Assessment Criteria: 1. The learner will understand the main approaches used in AI problem solving. [1.1, 1.2, 1.3] 2. The learner will be able to critically compare and contrast various knowledge representation systems. [2.1, 2.2, 2.3, 2.4, 2.5] 4. The learner will understand concepts and appreciate the significance of issues relevant to adaptive computing. [4.1, 4.2, 4.3] 5. The learner will know methods used in adaptive computing and understand how to apply them to problem solving. [5.1, 5.2, 5.3, 5.4, 5.5] 6. The learner will know the major AI application areas and understand the AI techniques used within them. [6.3, 6.4, 6.5] Indicative solution Procedural: represents progression towards a goal. Declarative: represents static factual/conditional factual propositions. Data driven: solutions derived from awareness of all relevant facts for the problem. Goal: solutions derived from efforts to satisfy problem related goals. Abductive reasoning: reasoning from exemplifier to explanatory theory based on possibilities only. Explanation may be wrong, but appears to be plausible. Examples of each of these concepts should be included in the answer. For instance, forward and backward chaining should be described with a real knowledge base of rules. Also, examples of procedural and declarative knowledge representations should be included. 10 EXAMINER’S COMMENTS A5.i a) Answers confused knowledge “type” with knowledge “representation”, so discussed procedural and declarative representations instead of the knowledge itself. A5.ii a) Question answered well on the whole, though some answers did not include clear examples of data and goal driven reasoning to illustrate. A5.iii a) Few answers explained abductive reasoning well. Some referred to CBR and analogical reasoning as equivalents without explaining the process of hypotheses generation fully. 11