NPTEL DATA MINING WEEK 2 ANSWERS

 

Week 2 : Assignment 2

Due date: 2023-02-08, 23:59 IST.

Assignment not submitted

If a store has N items, the number of possible itemsets is

 a. 2N-1

 b. 2N-1

 c. N/2

 d. N-1

An association rule is valid if it satisfies:

 a. Support criteria

 b. Confidence criteria

 c. Both support and confidence criteria

 d. None of these

An itemset is frequent if it satisfies the:

 a. Support criteria

 b. Confidence criteria

 c. Both support and confidence criteria

 d. None of these

Which of the following property is used by the apriori algorithm:

 a. Positive definiteness property of support

 b. Positive semidefiniteness property of support

 c. Monotone property of support

 d. Antimonotone property of support

Consider three itemsets I1={bat, ball, wicket}, I2={bat, ball}, I3={bat}. Which of the following statements are correct?

 a. support(I1) > support(I2)

 b. support(I2) > support(I3)

 c. both statements A and B

 d. none of the statements A and B

For questions 6-10, consider the following small database of four transactions. The minimum support is 60% and the minimum confidence is 80%.

Trans_id              Itemlist

T1                          {F, A, D, B}

T2                          {D, A, C, E, B}

T3                          {C, A, B, E}

T4                          {B, A, D}

The 1-itemsets that satisfy the support criteria are:

 a. {A}, {B}, {C}, {D}

 b. {A}. {B}, {C}

 c. {A}, {B}

 d. None of these

The 2-itemsets that satisfy the support criteria are:

 a. {BC}, {BE}, {CE}, {AE}

 b. {AB}. {BD}, {AD}

 c. {AE}, {BC}

 d. {BC}

The 3-itemsets that satisfy the support criteria are:

 a. {ABC}, {ABE}, {BCD}, {ACD}

 b. {ABE}. {BCD}, {ACD}

 c. {ABE}, {BCD}

 d. {ABD}

Which of the following is NOT a valid association rule?

 a. A -> B

 b. B -> A

 c. A -> D

 d. D -> A

Which of the following is NOT a valid association rule?

 a. A -> DB

 b. D -> AB

 c. AD -> B

 d. DB -> A

ANSWERS:

1. B

2. C

3. A

4. D

5. D

6. C

7. B

8. D

9. C

10. A