CS7641 FINAL EXAM 2025 UPDATE WITH COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED A+|BRAND NEW VERSION!!

CS7641 FINAL EXAM 2025 UPDATE WITH COMPLETE QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY
GRADED A+|BRAND NEW VERSION!!




Four optimization approaches - CORRECT ANSWER-1) Generate and test

2) Calculus

3) Newton's Method

4) Randomized Optimization



Hill Climbing Algorithm - CORRECT ANSWER-Guess x∈X

Repeat the following:

Let n*=argmax_n∈N(x) f(n)

If f(n)>f(x): x=n

Else: stop



Disadvantage:

- Get stuck in local optima



Randomized Restart Hill Climbing - CORRECT ANSWER-Same as Hill Climbing but
once local optimum reached, restart again with a different starting x

, Advantage:

- Won't get stuck in local optimum

- Not much more expensive than HC (constant factor)

Disadvantage:

- May not do better than enumeration (depends on size of attraction basin
around global optimum)



Entropy - CORRECT ANSWER--∑p(s)log₂p(s)



Number of bits per symbol (probability of symbol X # of bits to describe that
symbol)



Joint Entropy - CORRECT ANSWER-H(x,y)=-∑p(x,y)log₂p(x,y)



Randomness contained in two variables together



Conditional Entropy - CORRECT ANSWER-H(y|x)=-∑p(x,y)log₂p(y|x)



Randomness of one variable given the other variable



Entropy if x and y are independent - CORRECT ANSWER-H(Y|X)=H(Y) Y doesn't
get any info from x

H(X,Y)=H(X)+H(Y) Joint entropy is sum



Mutual Information - CORRECT ANSWER-I(x,y)=H(y)-H(y|x)=I(y,x)