1. P1WU
UNIT – III: CLASSIFICATION
Topic 9: EVALUATION METRICS
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
2. UNIT III : TEXT CLASSIFICATION AND CLUSTERING
1.A Characterization of Text
Classification
2. Unsupervised Algorithms:
Clustering
3. Naïve Text Classification
4. Supervised Algorithms
5. Decision Tree
6. k-NN Classifier
7. SVM Classifier
8. Feature Selection or Dimensionality
Reduction
9. Evaluation metrics
10. Accuracy and Error
11. Organizing the classes
12. Indexing and Searching
13. Inverted Indexes
14. Sequential Searching
15. Multi-dimensional Indexing
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
3. EVALUATION METRICS
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
4. EVALUATION METRICS
• Evaluating the Accuracy of a Classifier
• Basic Evaluation Measures for Classifier Performance.
• In Bioinformatics and machine learning in general,
• there is a large variation in the measures that are used to evaluate
prediction systems.
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
5. A confusion matrix
• For simplicity, the assumption is that each instance can only be assigned
one of two classes:
• Positive or
• Negative
(e.g. a patient's tumor may be malignant or benign).
• Each instance (e.g. a patient) has a Known label, and a Predicted label.
• Some method is used (e.g. cross-validation) to make predictions on each
instance. Each instance then increments one cell in the confusion matrix.
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
6. EVALUATION METRICS: -A confusion matrix
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
Predicted Label
Positive Negative
Known Label
Positive
True Positive
False
Negative
(TP) (FN)
Negative
False
Positive
True
Negative
(FP) (TN)
7. EVALUATION METRICS
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
8. CONTINGENCY TABLE
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
9. CONTINGENCY TABLE
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES
10. Any Questions?
AALIM MUHAMMED SALEGH COLLEGE OF ENGINEERING
DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING
SEMESTER – VIII
PROFESSIONAL ELECTIVE – IV
CS8080- INFORMATION RETRIEVAL TECHNIQUES