DBN and HMM and KFM and MRF and IsingM

BN is probability DAG, the node is variable, the edge is relationship of probability.

DBN is the dynamic version, which means it is used for dynamic variables, does not mean it is changing dynamic. so

1) the relationship is common law never changed, but you may only use part of the common law in one time slice. for example, in HMM, the state variable is changing. In one time , you are in stateA, then you use the observing law about stateA. In another time, you are in stateB, then you use the observing law about stateB.

2) In the DAG, there are nodes coming from the past time. given you all the time slices, the DBN can be viewed as BN, which has edges from nodes of time k-m to nodes of time k. For example, in KFM and HMM, m is always 1 or 0.

HMM is a special case of DBN, in which,

1)a can-not-see variable(state variable) is discrete variable.

2)the nodes from the past of time k-1 is used only.

KFM is a special case of DBN, in which,

1) a can-not-see variable(state variable) is continuous variable.

2) the nodes from the past of time k-1 is used only.

In a way, the BN or DBN is trying to utilize the independence of variables to make the graph look simple, have few edges，also called “Sparsity”. So you can avoid too much contional rules, like P(A|B|C|D). Given you a BN, you can know who and who are independent, who and who are not, and the probability path from one variable to another.

As for undirected graphic, there are MRF, which is a special case of Ising Model. They can represent cycling, but can not represent induced dependencies.

Give up the first choice

My starting point is the logic of human doctor, i guess that is why i did not get that much out the research.

When i saw the so-called "four steps" human doctors take to analyze ECG, i thought, oh, there are not so many steps, only four or five. Check the width of QRS, Check the presentation of P wave, Check the RR interval, check the ST changes.

But I should say i underestimate the work human has done, and overestimate the computer could do. And i may also underestimate the previous researchers' ability.

Why Researchers choose HMM + Wavelet, ANN, template matching, because these method is dummy way, you do not need to think too much, no logic, no rules, you just do it. That style agrees with computers.

" Ideas, and Formalization."

Whatever, i have to give up the current thought, not all, but trying to use computer implement human logic.

Damn, time is flying, so many ideas need to be verified.

Template & Model

In data-driven algorithm, we must use heuristic programming to simplify the analyzing procedure.

Using Template, it is simplified.

In model-driven algorithm, we must use heuristic programming to simplify the fitting procedure.

Using Template, it is induced.

Sixth Sense？

It does give you a lot of application that is new. Thus make the cell phone an interface between real world and the computing world and the network world. Combination is powerful.

But the thing i saw behind is the embarrassment of the speech recognition. Because the failure of the speech recognition which make so many application based on vision-recognition. And it is the failure of vision-recognition, which make the colorful application with network to make u ignore the baby skills of pattern recognition. But the success of network is the core instead of AI.

Python

i am so lazy, to avoid writing my own Continuous Boltzmann Machine, I spent one day to learn some basic knowledge of Python. Right now i am trying to convert it into Matlab code. Some thing really tricky is the vector & matrix multiplication, dot, outer, etc.

It is not so hard to know basic rules, but the libraries such as scipy, numpy, psyco, pylab do caught me for a whole afternoon.

The language agrees with me in its neat and natural language-like grammar. Kind of love it, but for a 30-year-old man, whether to learn it is still not fixed.

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