Website chia sẻ tài liệu, ebook tham khảo cho các bạn học sinh, sinh viên
An ROC curve is plotted as follows. Starting at the bottom-left hand corner (where the TPF and FPP are both 0), we check the actual class label of the tuple at the top of the list. If we have a true positive then on the ROC curve, we move up and plot a point. If, the tuple really belongs to the ‘no’ class, we have a false positive, on the ROC curv...
22 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1016 | Lượt tải: 0
The quadratic programming differs from the linear programming only in that the objective function also include xj2 and xixj (i j) terms. If we used matrix notation, the problem is to find x so as to Maximize f(x) = cx – (1/2)xTQx, subject to Ax b and x 0 where c is a row vector, x and b are column vectors, Q and A are matrices. The qij...
45 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1034 | Lượt tải: 0
Pruning If the tree is grown too large, it can be pruned by trimming in a bottom-up fashion. All pairs of neighboring leaf nodes (i.e. ones linked to a common parent) are considered for elimination. Any pair whose elimination results in a satisfactory (small) increase in impurity is eliminated, and the common parent node becomes a leaf node. (Thi...
30 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 983 | Lượt tải: 0
Prior probability: probability in the absence of any other information P(A): probability of event A Example: P(Dice = 2) = 1/6 random variable: Dice domain = <1, 2, 3, 4, 5, 6> probability distribution: P(Dice) = <1/6, 1/6, 1/6, 1/6, 1/6, 1/6>
27 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1077 | Lượt tải: 0
Conclusions The nearest-neighbor classifiers are appealing and effective. The drawback is in the implementation: high computational time and space for large training data. To reduce the computation time, various approaches have been proposed which help retrieve the nearest neighbors in a short time (e.g. using the support of some data structures...
34 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1008 | Lượt tải: 0
The Cayley-Hamilton Theorem In practical calculation, we set the characteristic polynomial equal to zero, given the characteristic equation: det |A - I| = 0 The zeros of the characteristic polynomial, which are solutions to this equation, are the eigenvalues of the matrix A. The second step in solving the eigenvalue problem is to find the eig...
76 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1112 | Lượt tải: 0
5. Two paradigms of pattern recognition There are several paradigms which have been used to solve the pattern recognition problem. The two main ones are statistical pattern recognition and syntactic pattern recognition In statistical pattern recognition, we use vector spaces to represent patterns and classes. The abstractions deal with probabili...
18 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 890 | Lượt tải: 0
Recap Designing a Set of Relations Properties of Relational Decompositions Algorithms for Relational Database Schema Multivalued Dependencies and Fourth Normal Form Join Dependencies and Fifth Normal Form Inclusion Dependencies Other Dependencies and Normal Forms
8 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 952 | Lượt tải: 0
Chapter Outline Informal Design Guidelines for Relational Databases Functional Dependencies (FDs) Definition, Inference Rules, Equivalence of Sets of FDs, Minimal Sets of FDs Normal Forms Based on Primary Keys General Normal Form Definitions (For Multiple Keys) BCNF (Boyce-Codd Normal Form)
9 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 1533 | Lượt tải: 0
Summary Assertions provide a means to specify additional constraints Triggers are assertions that define actions to be automatically taken when certain conditions occur Views create temporary (virtual) tables A database may be accessed in an interactive mode Most often, however, data in a database is manipulate via application pro...
7 trang | Chia sẻ: vutrong32 | Ngày: 17/10/2018 | Lượt xem: 962 | Lượt tải: 0