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    UNIT-I

    PART - A

    1. Define Artificial Intelligence formulated by Haugeland.

    The exciting new effort to make computers think machines with minds in the full and literal

    sense.

    2. Define Artificial Intelligence in terms of human performance.

    The art of creating machines that perform functions that require intelligence when performed by

    people.

    3. Define Artificial Intelligence in terms of rational acting.

    A field of study that seeks to explain and emulate intelligent behaviors in terms of computationalprocesses-Schalkoff. The branch of computer science that is concerned with the automation of

    intelligent behavior-Luger&Stubblefield.

    3. Define Artificial in terms of rational thinking.

    The study of mental faculties through the use of computational models-Charniak&McDermott.

    The study of the computations that make it possible to perceive, reason and act-Winston.

    4. What does Turing test mean?

    The Turing test proposed by Alan Turing was designed to provide a satisfactory operational

    definition of intelligence. Turing defined intelligent behavior as the ability to achieve human-

    level performance in all cognitive tasks, sufficient to fool an interrogator.

    Natural Language Processing:

    To enable it to communicate successfully in English.

    Knowledge Representation:

    To store information provided before or during interrogation.

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    Automated Reasoning:

    To use the stored information to answer questions and to draw new conclusion.

    Machine Language:

    To adapt new circumstances and to detect and explorate pattern.

    5. Define an agent.

    An agent is anything that can be viewed as perceiving its environment through sensors and

    acting upon the environment through effectors.

    7. Define rational agent.

    A rational agent is one that does the right thing. Here right thing is one that will cause agent to bemore successful. That leaves us with the problem of deciding how and when to evaluate the

    agents success.

    8. Define an Omniscient agent.

    An omniscient agent knows the actual outcome of its action and can act accordingly; but

    omniscience is impossible in reality.

    9. What are the factors that a rational agent should depend on at any given time?

    1. The performance measure that defines degree of success.

    2. Ever thing that the agent has perceived so far. We will call this

    complete perceptual history the percept sequence.

    3. When the agent knows about the environment.

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    4. The action that the agent can perform.

    10. Define an Ideal rational agent.

    For each possible percept sequence, an ideal rational agent should do whatever action is expected

    to maximize its performance measure on the basis of the evidence provided by the percept

    sequence & whatever built-in knowledge that the agent has.

    11. Define an agent program.

    Agent program is a function that implements the agents mapping from percept to actions.

    12. Define Architecture.

    The action program will run on some sort of computing device which is called as Architecture.

    13. List the various type of agent program.

    Simple reflex agent program.

    Agent that keep track of the world.

    Goal based agent program.

    Utility based agent program

    14. State the various properties of environment.

    Accessible Vs Inaccessible:

    If an agents sensing apparatus give it access to the complete state of the environment then we

    can say the environment is accessible to he agent.

    Deterministic Vs Non deterministic:

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    20. Differentiate blind search & heuristic search.

    Blind search has no information about the no. of steps or the path cost from the current state to

    the goal, they can distinguish a goal state from nongoal state. Heuristic search-knowledge given.

    Problem specification solution is best.

    21. List the various search strategies.

    a. BFS

    b. Uniform cost search

    c. DFS

    d. Depth limited search

    e. Iterative deepening search

    f. Bidirectional search

    21. List the various informed search strategy.

    Best first search greedy search

    A* search

    Memory bounded search-Iterative deepening A*search

    simplified memory bounded A*search

    Iterative improvement search hill climbing

    simulated annealing

    23. Differentiate BFS & DFS.

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    BFS means breath wise search DFS means depth wise search

    BFS DFS

    Space complexity is more Space complexity is less

    Do not give optimal solution Gives optimal solution

    Queuing fn is same as that of queue operator Queuing fn is somewhat different

    from queue operator

    24. Whether uniform cost search is optimal?

    Uniform cost search is optimal & it chooses the best solution depending on the path cost.

    25. Write the time & space complexity associated with depth limited search.

    Time complexity =O (bd) , b-branching factor, d-depth of tree

    Space complexity=O(bl)

    26. Define iterative deepening search.

    Iterative deepening is a strategy that sidesteps the issue of choosing the best depth limit by trying

    all possible depth limits: first depth 0, then depth 1,then depth 2& so on.

    27. Define CSP

    A constraint satisfaction problem is a special kind of problem satisfies some additional structuralproperties beyond the basic requirements for problem in general. In a CSP; the states are defined

    by the values of a set of variables and the goal test specifies a set of constraint that the value

    must obey.

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    28. Give the drawback of DFS.

    The drawback of DFS is that it can get stuck going down the wrong path. Many problems have

    very deep or even infinite search tree. So dfs will never be able to recover from an unlucky

    choice at one of the nodes near the top of the tree.SoDFS should be avoided for search trees with

    large or infinite maximum depths.

    29. What is called as bidirectional search?

    The idea behind bidirectional search is to simultaneously search both forward from the initial

    state & backward from the goal & stop when the two searches meet in the middle.

    30. Explain depth limited search.

    Depth limited avoids the pitfalls of DFS by imposing a cut off of the maximum depth of a path.

    This cutoff can be implemented by special depth limited search algorithm or by using the general

    search algorithm with operators that keep track of the depth.

    31. Differentiate greedy search & A* search.

    Greedy Search

    If we minimize the estimated cost to reach the goal h(n), we get greedy search The search time is

    usually decreased compared to uniformed alg, but the alg is neither optimal nor complete

    32 . Give the procedure of IDA* search.

    Minimize f(n)=g(n)+h(n) combines the advantage of uniform cost search + greedy search A* is

    complete, optimal Its space complexity is still prohibitive.

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    Iterative improvement algorithms keep only a single state in memory, but can get stuck on localmaxima. In this alg each iteration is a dfs just as in regular iterative deepening. The depth first

    search is modified to use an f-cost limit rather than a depth limit. Thus each iteration expands

    A*search

    all nodes inside the contour for the current f-cost.

    33. What is the advantage of memory bounded search techniques?

    We can reduce space requirements of A* with memory bounded alg such as IDA* & SMA*.

    34. List some properties of SMA* search.

    * It will utilize whatever memory is made available to it.

    * It avoids repeated states as for as its memory allow.

    * It is complete if the available memory is sufficient to store the shallowest path.

    * It is optimal if enough memory is available to store the shallowest optimal solution path.

    Otherwise it returns the best solution that can be reached with the available memory.

    *When enough memory is available for entire search tree, the search is optimally efficient.

    *Hill climbing.

    *Simulated annealing.

    35. List some drawbacks of hill climbing process.

    Local maxima: A local maxima as opposed to a goal maximum is a peak that is lower that the

    highest peak in the state space. Once a local maxima is reached the algorithm will halt even

    though the solution may be far from satisfactory.

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    Plateaux: A plateaux is an area of the state space where the evaluation fn is essentially flat. The

    search will conduct a random walk.

    36. List the various AI Application Areas

    natural language processing - understanding,

    generating, translating;

    planning;

    vision - scene recognition, object recognition, face

    recognition;

    robotics;

    theorem proving;

    speech recognition;

    game playing;

    problem solving;

    expert systems etc

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    PART- B QUESTIONS

    1. Explain the following uninformed search strategies with examples.

    i. ( i )Breadth First search

    ii. ( ii)Depth First search

    iii. (iii)Depth limited search

    iv. (iv)Uniform cost search

    2. Explain in detail about the heuristic function.

    3. What are constraint satisfaction problem? How can you formulate them as

    search problem?

    4. Explain in detail Model based reflex agent.

    5. Explain in detail Goal based reflex agent.

    6. Explain in detail Utility based reflex agent.

    7. Explain in detail Learning agent.

    8. Explain in detail Problem solving agent.

    9. Write in detail about any two informed search strategies.

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    PART - A

    1. What are Logical agents

    Logical agents apply inference to a knowledge base to derive new information and make

    decisions.

    2. What are the limitations of simple reflex agents

    Reflex agents are also unable to avoid infinite loops

    In Wumpus world -A pure reflex agent cannot know for sure when to Climb, because neither

    having the gold nor being in the start square is part of the percept; they are things the agent

    knows by forming a representation of the world.

    3. What are Causal Rules?

    Causal rules reflect the assumed direction of causality in the world:

    (Al1,l2,s) At(Wumpus,l1,s) ^ Adjacent(l1,l2) => Smelly(l2)

    (A l1,l2,s) At(Pit,l1,s) Adjacent(l1,l2) => Breezy(l2)

    Systems that reason with causal rules are called model-based reasoning systems

    4. What is Situation Calculus?

    A situation is a snapshot of the world at an interval of time during which nothing changes

    Every true or false statement is made with respect to a particular situation.

    Add situation variables to every predicate.

    at(hunter,1,1) becomes at(hunter,1,1,s0): at(hunter,1,1) is true in situation (i.e., state) s0.

    Example: The action agent-walks-to-location-y could be represented by

    s) (at(Agent,x,s) ^ ~onbox(s)) -y)(x)((> at(Agent,y,result(walk(y ),s))

    5. What are Diagnostic rules?

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    Diagnostic rules infer the presence of hidden properties directly from the percept-derived

    information. We have already seen two diagnostic rules:

    (A l,s) At(Agent,l,s) Breeze(s) => Breezy(l)

    (A l,s) At(Agent,l,s) Stench(s) => Smelly(l)

    6. Give an example rule for Goal Based Agent.

    Once the gold is found, it is necessary to change strategies. So now we need a new set of action

    values.

    We could encode this as a rule:

    a. s) Holding(Gold,s) =(> GoalLocation([1,1]),s)

    7. What are the components of Propositional Logic?

    Logical constants: true, false

    Propositional symbols: P, Q, S, ... (atomic sentences)

    Wrapping parentheses: ( )

    Sentences are combined by connectives:

    ...and [conjunction]

    ...or [disjunction]

    ...implies [implication / conditional]

    ..is equivalent [biconditional]

    ...not [negation]

    Literal: atomic sentence or negated atomic sentence

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    8. What is Horn Clause?

    A Horn sentence or Horn clause has the form:

    Pn P3 ... P2 P1 Q

    or alternatively

    Q Pn P3 ... P2 P1

    where Ps and Q are non-negated atoms

    To get a proof for Horn sentences, apply Modus Ponens repeatedly until nothing can be done

    9. Define First Order Logic.

    First-order logic (FOL) models the world in terms of

    Objects, which are things with individual identities

    Properties of objects that distinguish them from other objects

    Relations that hold among sets of objects

    Functions, which are a subset of relations where there is only one value for any given input

    Examples:

    Objects: Students, lectures, companies, cars ...

    Relations: Brother-of, bigger-than, outside, part-of, has-color, occurs-after, owns, visits,

    precedes, ...

    Properties: blue, oval, even, large, ...

    Functions: father-of, best-friend, second-half, one-more-than ...

    10. What are the types of Quantifiers?

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    Universal Quantifiers & Existential Quantifiers

    11. What is Universal Quantification?

    Universal quantification

    a. x)P(x) means that P holds for all values of x in the domain associated with that variable(

    b. mammal(x)x) dolphin(x) E.g., (

    12. What is Existential quantification

    a. x)P(x) means that P holds for some value of x in the domain associated with that variable(

    b. lays-eggs(x) x) mammal(x) E.g., (

    c. Permits one to make a statement about some object without naming it

    Connections between All and Exists

    13. Define a knowledge Base

    Knowledge base is the central component of knowledge base agent and it

    is described as a set of representations of facts about the world.

    14. Define a Sentence?

    Each individual representation of facts is called a sentence. The

    sentences are expressed in a language called as knowledge representation

    language.

    15. Define an inference procedure

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    is entiled by An inference procedure reports whether or not a sentence

    . An inferenceknowledge base provided a knowledge base and a sentence

    procedure i can be described by the sentences that it can derive.

    from knowledge base, we can write. If i can derive

    Alpha is derived from KB or i derives alpha from KB KB

    16. What are the three levels in describing knowledge based agent?

    Logical level

    Implementation level

    Knowledge level or epistemological level

    17. Define Syntax?

    Syntax is the arrangement of words. Syntax of a knowledge describes the

    possible configurations that can constitute sentences. Syntax of the language

    describes how to make sentences.

    18. Define Semantics

    The semantics of the language defines the truth of each sentence with

    respect to each possible world. With this semantics, when a particular configuration

    exists with in an agent, the agent believes the corresponding sentence.

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    19. Define Logic

    Logic is one which consist of

    i. A formal system for describing states of affairs, consisting

    of a) Syntax b)Semantics.

    ii. Proof Theory a set of rules for deducing the entailment of a set sentences.

    20. What is entailment

    The relation between sentence is called entailment. The formal definition

    of entailment is this: if and only if in every model in which is true, is also true or if is true then

    must also be true. Informally the truth of is contained in the truth of .

    21. What is truth Preserving

    An inference algorithm that derives only entailed sentences is called

    sound or truth preserving .

    22. Define a Proof

    A sequence of application of inference rules is called a proof. Finding

    proof is exactly finding solution to search problems. If the successor function is

    defined to generate all possible applications of inference rules then the search

    algorithms can be applied to find proofs.

    23. Define a Complete inference procedure

    An inference procedure is complete if it can derive all true conditions from

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    a set of premises.

    24. Define Interpretation

    Interpretation specifies exactly which objects, relations and functions are

    reffered to by the constant predicate, and function symbols.

    25. Define Validity of a sentence

    A sentence is valid or necessarily true if and only if it is true under all

    possible interpretation in all posssible world.

    26. Define Satistiability of a sentence

    A sentence is satisfiable if and only if there is some interpretation in some

    world for which it is true.

    27. Define true sentence

    A sentence is true under a particular interpretation if the state of affairs it

    represents is the case.

    28. What are the basic Components of propositonal logic?

    i. Logical Constants (True, False)

    29. Define Modus Ponens rule in Propositional logic?

    The standard patterns of inference that can be applied to derive chains of

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    conclusions that lead to the desired goal is said to be Modus Ponens rule.

    30. Define AND Elimination rule in propositional logic

    AND elimination rule states that from a given conjunction it is possible to

    inference any of the conjuncts.

    n ------^1 ^

    i 2

    31.Define AND-Introduction rule in propositional logic

    AND-Introduction rule states that from a list of sentences we can infer their conjunctions

    2,..,

    ^.^^12n1n

    32. Define OR-Introduction rule in propositonal logic

    1

    ____________________

    n2vv1v

    OR-Introduction rule states that from, a sentence, we can infer its disjunction with

    anything.

    PART- B QUESTIONS

    1. Explain the backward chaining algorithm.

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    2. Explain alpha-beta pruning algorithm with its procedure.

    3. Explain the resolution for first order logic and inference rule

    4. Illustrate the use of first-order-logic to represent the knowledge.

    5. Explain the unification algorithm with an example.

    6. Explain the unification algorithm with an example.

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    UNIT-III

    PART - A

    1. Define state space search

    The most straightforward approach is to use state-space search. Because the descriptions of

    actions in a planning problem specify both preconditions and effects, it is possible to search in

    either direction: either forward from the initial state or backward from the goal

    2. What are the types of state space search

    Forward state space search & Backward state space search

    3. Define Forward state-space search

    It is sometimes called progression planning, because it moves in the forward direction.

    4. What are the advantages of Backward state-space search

    The main advantage of backward search is that it allows us to consider only relevant actions.

    5. Define Partial-Order Planning

    A set of actions that make up the steps of the plan. These are taken from the set of actions in theplanning problem. The empty plan contains just the Start and Finish actions. Start has no

    preconditions and has as its effect all the literals in the initial state of the planning problem.

    Finish has no effects and has as its preconditions the goal literals of the planning problem.

    6. What are the advantages of Partial-Order Planning

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    Partial-order planning has a clear advantage in being able to decompose problems into subproblems. It also has a disadvantage in that it does not represent states directly, so it is harder to

    estimate how far a partial-order plan is from achieving a goal.

    7. What are Planning Graphs

    A Planning graph consists of a sequence of levels that correspond to time steps in the plan where

    level 0 is the initial state. Each level contains a set of literals and a set of

    Actions

    8. What is Conditional planning?

    Also known as contingency planning, conditional planning deals with incomplete information byconstructing a conditional plan that accounts for each possible situation or contingency that

    could arise

    9. What is action plan?

    The process of checking the preconditions of each action as it is executed, rather

    than checking the preconditions of the entire remaining plan. This is called action monitoring

    10. Define planning.

    Planning can be viewed as a type of problem solving in which the agent

    uses beliefs about actions and their consequences to search for a solution.

    11. What are the features of an ideal planner?

    i. The planner should be able to represent the states, goals and actions.

    ii. The planner should be able to add new actions at any time.

    iii. The planner should be able to use Divide and Conquer method for

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    solving very big problems.

    12. What are the components that are needed for representing an action?

    The components that are needed for representing an action are:

    i. Action description.

    ii. Precondition.

    iii. Effect.

    13. What are the components that are needed for representing a plan?

    The components that are needed for representing a plan are:

    i. A set of plans steps.

    ii. A set of ordering constraints.

    iii. A set of variable binding constraints.

    iv. A set of casual link protection.

    14. What are the different types of planning?

    The different types of planning are as follows:

    i. Situation space planning.

    ii. Progressive planning.

    iii. Regressive planning.

    iv. Partial order planning.

    v. Fully instantiated planning.

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    15. What are the ways in which incomplete and incorrect informations can be handled in

    planning?

    They can be handled with the help of two planning agents namely,

    i. Conditional planning agent.

    ii. Replanning agent.

    16. Define a solution.

    A solution is defined as a plan that an agent can execute and that guarantees the achievement of

    goal.

    17. Define a complete plan.

    A complete plan is one in which every precondition of every step is achieved by some other step.

    18. Define a consistent plan.

    A consistent plan is one in which there are no contradictions in the ordering or binding

    constraints.

    19. Define conditional planning.

    Conditional planning is a way in which the incompleteness of information is incorporated in

    terms of adding a conditional step, which involves if then rules.

    20. Give the classification of learning process.

    The learning process can be classified as:

    i. Process which is based on coupling new information to previously

    acquired knowledge

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    a. Learning by analyzing differences.

    b. Learning by managing models.

    c. Learning by correcting mistakes.

    d. Learning by explaining experience.

    ii. Process which is based on digging useful regularity out of data,

    usually called as Data base mining:

    a. Learning by recording cases.

    b. Learning by building identification trees.

    c. Learning by training neural networks.

    21. What is Induction heuristics?

    Induction heuristics is a method, which enable procedures to learn descriptions from positive and

    negative examples.

    22. What are the different types of induction heuristics?

    There are two different types of induction heuristics. They are:

    i. Require-link heuristics.

    ii. Forbid-link heuristics.

    23. What are the principles that are followed by any learning procedure?

    i. The wait and see principle.

    ii. The no altering principle.

    iii. Martins law.

    24. State the wait and see principle.

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    The law states that, When there is doubt about what to do, do nothing

    25. State the no altering principle.

    The law states that, When an object or situation known to be an example, fails to match a

    general model, create a special case exception model.

    26. State Martins law.

    The law states that, You cannot learn anything unless you almost know it already.

    27. Define Similarity nets.

    Similarity net is an approach for arranging models. Similarity net is a representation in which

    nodes denotes models, links connect similar models and links are tied to different descriptions.

    28. Define Reification.

    The process of treating something abstract and difficult to talk about as though it were concrete

    and easy to talk about is called as reification.

    29. What is reified link?

    The elevation of a link to the status of a describable node is a kind of reification. When a link is

    so elevated then it is said to be a reified link.

    30. Define Backward state-space search

    It searches backward from the goal situation to the initial situation.

    31. Differentiate between Partial Order Plan & Total order plan.

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    Partial-order plan

    consists partially ordered set of actions

    sequence constraints exist on these actions

    plan generation algorithm can be applied to transform partial-order plan to total-order plan

    Total-order plan

    consists totally ordered set of actions

    32. Define action monitoring

    The process of checking the preconditions of each action as it is executed, rather than checkingthe preconditions of the entire remaining plan. This is called action monitoring.

    33. What is meant by Execution monitoring

    Execution monitoring is related to conditional planning in the following way. An agent thatbuilds a plan and then executes it while watching for errors is, in a sense, taking into account the

    possible conditions that constitute execution errors.

    34. List the two different ways to deal with the problems arising from incomplete and incorrect

    information

    Conditional planning

    Execution monitoring

    35. Differentiate between Forward state-space search and Backward state-space search.

    1. Forward state-space search : It searches forward from the initial situation to the goal situation.

    2. Backward state-space search: It searches backward from the goal situation to the initial

    situation.

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    36. What are the steps of planning problems using state space research

    methodology?

    The initial state of the search is the initial state from the planning problem. In general,

    each state will be a set of positive ground literals; literals not appearing are false.

    The actions that are applicable to a state are all those whose preconditions are satisfied.

    The successor state resulting from an action is generated by adding the positive effect

    literals and deleting the negative effect literals. (In the first-order case, we must apply

    the unifier from the preconditions to the effect literals.) Note that a single successor

    function works for all planning problemsa consequence of using an explicit action

    representation.

    The goal test checks whether the state satisfies the goal of the planning problem.

    The step cost of each action is typically 1. Although it would be easy to allow different

    costs for different actions, this is seldom done by STRIPS planners.

    37. What is the function of a replanning agent?

    A simple replanning agent uses execution monitoring and splices in subplans as needed.

    PART- B QUESTIONS

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    1. Explain about partial order planning with an example.

    2. Explain about the different types of state space searches.

    3. Explain about partial order planning algorithm.

    4. Describe in detail about planning graphs.

    5. Explain in detail about graph plan algorithm.

    6. Explain in detail about conditional planning with an example.

    7. Explain about replanning agent algorithm.

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    PART - A

    1. Why does uncertainty arise ?

    Agents almost never have access to the whole truth about their

    environment.

    Agents cannot find a caterorial answer.

    Uncertainty can also arise because of incompleteness, incorrectness in

    agents understanding of properties of environment.

    2. State the reason why first order, logic fails to cope with that the mind like

    medical diagnosis.

    Three reasons

    a.laziness:

    it is hard to lift complete set of antecedents of consequence,

    needed to ensure and exceptionless rule.

    b. Theoritical Ignorance:

    medical science has no complete theory for the domain.

    Practical ignorance:

    even if we know all the rules, we may be uncertain about a particular item needed.

    2. Define the term utility?

    The term utility is used in the sense of \"the quality of being useful .\", utility of a state is relative

    to the agents, whose preferences the utility function is supposed to represent.

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    3. What is the need for probability theory in uncertainty ?

    Probability provides the way of summarizing the uncertainty that comes from our laziness and

    ignorance . Probability statements do not have quite the same kind of semantics known asevidences.

    5. What is the need for utility theory in uncertainty?

    Utility theory says that every state has a degree of usefulness, or utility to In agent, and that the

    agent will prefer states with higher utility. The use utility theory to represent and reason with

    preferences.

    6. What is called as principle of maximum expected utility ?

    The basic idea is that an agent is rational if and only if it chooses the action that yields the

    highest expected utility, averaged over all the possible outcomes of the action. This is known as

    MEU.

    7. What Is Called As Decision Theory ?

    Preferences As Expressed by Utilities Are Combined with Probabilities in the General Theory of

    Rational Decisions Called Decision Theory. Decision Theory = Probability Theory + Utility

    Theory.

    8. Define Prior Probability?

    p(a) for the Unconditional or Prior Probability Is That the Proposition A is True. It is important

    to remember that p(a) can only be used when there is no other information.

    9. Define conditional probability?

    Once the agents has obtained some evidence concerning the previously

    unknown propositions making up the domain conditional or posterior probabilities

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    with the notation p(A/B) is used. This is important that p(A/B) can only be used when all be is

    known.

    10. Define probability distribution:

    If we want to have probabilities of all the possible values of a random

    variable probability distribution is used.

    Eg.

    P(weather) = (0.7,0.2,0.08,0.02). This type of notations simplifies many equations.

    11. What is an atomic event?

    An atomic event is an assignment of particular values to all variables, in

    other words, the complete specifications of the state of domain.

    12. Define joint probability distribution

    This completely specifies an agent\'s probability assignments to all

    propositions in the domain.The joint probability distribution p(x1,x2,--------xn)

    assigns probabilities to all possible atomic events;where X1,X2------Xn=variables.

    13. Give the Baye\'s rule equation

    W.K.T P(A ^ B) = P(A/B) P(B) -------------------------- 1

    P(A ^ B) = P(B/A) P(A) -------------------------- 2

    DIVIDING BYE P(A) ; WE GET

    P(B/A) = P(A/B) P(B)

    --------------------

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    P(A)

    14. What is meant by belief network?

    A belief network is a graph in which the following holds

    A set of random variables

    A set of directive links or arrows connects pairs of nodes.

    The conditional probability table for each node

    The graph has no directed cycles.

    15. What are the ways in which one can understand the semantics of a belief

    network?

    There are two ways to see the network as a representation of the joint probability distribution to

    view it as an encoding of collection of conditional independence statements.

    16. What is the basic task of a probabilistic inference?

    The basic task is to reason in terms of prior probabilities of conjunctions, but for the most part,

    we will use conditional probabilities as a vehicle for probabilistic inference.

    17. What are called as Poly trees?

    The algorithm that works only on singly connected networks known as

    Poly trees. Here at most one undirected path between any two nodes is present.

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    18. Define casual support

    E+X is the casual support for X- the evidence variables \"above\" X that

    Are connected to X through its parent.

    19. Define evidential support

    E-X is the evidential support for X- the evidence variables \"below\" X that

    Are connected to X through its children.

    20. What is called as multiple connected graph?

    A multiple connected graph is one in which two nodes are connected by more than one path.

    21. List the 3 basic classes of algorithms for evaluating multiply connected graphs.

    Clustering methods

    Conditioning methods

    Stochastic simulation methods

    22. Define Uncertainty.

    Uncertainty means that many of the simplifications that are possible with deductive inference

    are no longer valid.

    23. What is meant by deterministic nodes?

    A deterministic node has its value specified exactly by the values of its parents, with no

    uncertainty.

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    24. What are all the various uses of a belief network?

    Making decisions based on probabilities in the network and on the agent\'s utilities.

    Deciding which additional evidence variables should be observed in order to gain useful

    information.

    Performing sensitivity analysis to understand which aspects of the model have the greatest

    impact on the probabilities of the query variables (and therefore must be accurate).

    Explaining the results of probabilistic inference to the user.

    25. What is the function of cutset conditioning method?

    This method transforms the network into several simpler polytrees.

    26. What is the use of Dempster- Shafer theory?

    It is designed to deal with the distinction between uncertainty and ignorance.

    27. What is the use of Fuzzy set theory?

    Fuzzy set theory is a means of specifying how well an object satisfies a vague description.

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    PART- B QUESTIONS

    1. Explain about Bayesian network with an example.

    2. Explain in detail about conditional probability.

    3. Explain about Markov Process.

    4. Explain in detail about dynamic Bayesian networks.

    5. Explain in detail about Enumeration algorithm.

    6. Explain about inference in Bayesian network

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    UNIT-V

    16 Marks

    1. Explain the stages in communication.

    2. Describe the augmented grammar.

    3. What is the probabilistic Language model? Explain.

    4. Describe the process involved in communication using the example sentence

    The wumpus is dead

    5. Write short notes on semantic interpretation?

    6. Illustrate the learning from examples by induction with suitable examples

    7 Explain briefly about the following Information retrieval

    8. Explain briefly about the following Information extraction

    PART - A

    1. What is meant by learning?

    Learning is a goal-directed process of a system that improves the knowledge or the knowledge

    representation of the system by exploring experience and prior knowledge.

    2. Define informational equivalence.

    A transformation from on representation to another causes no loss of information; they can be

    constructed from each other.

    3. Define computational equivalence.

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    The same information and the same inferences are achieved with the same amount of effort.

    4. List the difference between knowledge acquisition and skill refinement.

    knowledge acquisition (example: learning physics) learning new symbolic information

    coupled with the ability to apply that information in an effective manner

    skill refinement (example: riding a bicycle, playing the piano) occurs at a subconscious level

    by virtue of repeated practice

    5. What is meant by analogical reasoning?

    Instead of using examples as foci for generalization, one can use them directly to solve newproblems.

    6. Define Explanation-Based Learning.

    The background knowledge is sufficient to explain the hypothesis. The agent does not learn

    anything factually new from the instance. It extracts general rules from single examples by

    explaining the examples and generalizing the explanation

    7. What is meant by Relevance-Based Learning?

    uses prior knowledge in the form of determinations to identify the relevant attributes

    generates a reduced hypothesis space

    8. Define Knowledge-Based Inductive Learning.

    Knowledge-Based Inductive Learning finds inductive hypotheses that explain set of observations

    with the help of background knowledge.

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    9. What is truth preserving?

    An inference algorithm that derives only entailed sentences is called sound or truth preserving.

    10. Define Inductive learning.

    Learning a function from examples of its inputs and outputs is called inductive learning.

    11. How the performance of inductive learning algorithms can be measured?

    It is measured by their learning curve, which shows the prediction accuracy as a function of the

    number of observed examples.

    12. List the advantages of Decision Trees

    It is one of the simplest and successful forms of learning algorithm.

    It serves as a good introduction to the area of inductive learning and is easy to implement.

    13. What is the function of Decision Trees?

    A decision tree takes as input an object or situation by a set of properties, and outputs a yes/no

    decision. Decision tree represents Boolean functions.

    14. List some of the practical uses of decision tree learning.

    Designing oil platform equipment

    Learning to fly

    15. Define reinforcement learning.

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    The task of reinforcement learning is to use rewards to learn a successful agent function.

    16. Differentiate between Passive learner and Active learner.

    A passive learner watches the world going by, and tries to learn the utility of being in various

    states. An active learner acts using the learned information, and can use its problem generator to

    suggest explorations of unknown portions of the environment.

    17. State the design issues that affect the learning element.

    Which components of the performance element are to be improved

    What representation is used for those components

    What feedback is available

    What prior information is available

    18. State the factors that play a role in the design of a learning system.

    Learning element

    Performance element

    Critic

    Problem generator

    19. What is memoization?

    The technique of memorization is used to speed up programs by saving the results ofcomputation. The basic idea is to accumulate a database of input/output pairs; When the function

    is called, it first checks the database to see if it can avoid solving the problem from scratch.

    20. Define Q-Learning.

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    The agent learns an action-value function giving the expected utility of taking a given action in a

    given state. This is called Q-Learning.

    21. Differentiate between supervised learning & unsupervised learning.

    Any situation in which both inputs and outputs of a component can be perceived is called

    supervised learning. Learning when there is no hint at all about the correct outputs is called

    unsupervised learning.

    22. Define Ockhams razor.

    Extracting a pattern means being able to describe a large number of cases in a concise way.

    Rather than just trying to find a decision tree that agrees with example, try to find a concise one,too.

    23. Define Bayesian learning

    Bayesian learning simply calculates the probability of each hypothesis, given the data,

    and makes predictions on that basis. That is, the predictions are made by using all the

    hypotheses, weighted by their probabilities, rather than by using just a single best hypothesis.

    24. What is meant by hidden variables?

    Many real-world problems have hidden variables (sometimes called latent variables) which are

    not observable in the data that are available for learning.

    25. Define Cross validation.

    The basic idea behind Cross validation is try to eliminate how well the current hypothesis will

    predict unseen data.

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    Learning element is responsible for making improvements.

    30. List the 3 approaches that can be used to learn utilities.

    1. Least-mean-square Approach

    2. Adaptive Dynamic Programming Approach

    3. Temporal Difference Approach

    PART- B QUESTIONS

    1. Explain the learning decision tree with algorithm

    2. (i).Explain the explanation based learning?

    (ii).Explain how learning with complete data is achieved?

    3. Discuss learning with hidden variables?

    4. Explain all the statistical learning method available in AI.

    5. Explain about Reinforcement learning.