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Other versions will cause V(s) conversion to be *(s). In synchronized updates, it makes them just a tiny little bit faster [inaudible] and then it turns out the analysis of value iterations synchronous updates are also easier to analyze and that just matters [inaudible]. Asynchronous has been just a little bit faster.

So when you run this algorithm on the MDP – I forgot to say all these values were computed with gamma equals open 99 and actually, Roger Gross, who’s a, I guess, master [inaudible] helped me with computing some of these numbers. So you compute it. That way you run value relation on this MDP. The numbers you get for V* are as follows: .86, .90 – again, the numbers sort of don’t matter that much, but just take a look at it and make sure it intuitively makes sense.

And then when you plug those in to the formula for computing, that I wrote down earlier, for computing p* as a function of V*, then – well, I drew this previously, but here’s the optimal policy p*.

And so, just to summarize, the process is run value iteration to compute V*, so this would be this table of numbers, and then I use my form of p* to compute the optimal policy, which is this policy in this case.

Now, to be just completely concrete, let’s look at that free one state again. Is it better to go left or is it better to go north? So let me just illustrate why I’d rather go left than north. In the form of the p*, if I go west, then sum over s prime, P(s, a) s prime, P*(sp), this would be – well, let me just write this down. Right, if I go north, then it would be because of that. I wrote it down really quickly, so it’s messy writing. The way I got these numbers is suppose I’m in this state, in this free one state. If I choose to go west and with chance .8, I get to .75 – to this table -- .75. With chance .1, I veer off and get to the .69, then at chance .1, I go south and I bounce off the wall and I stay where I am.

So that’s why my expected future payoff for going west is .8 times .75, plus .1 times .69, plus .1 times .71, the last .71 being if I bounce off the wall to the south and then seeing where I am, that gives you .740.

You can then repeat the same process to estimate your expected total payoff if you go north, so if you do that, with a .8 chance, you end up going north, so you get .69. With a .1 chance, you end up here and .1 chance you end up there. This map leads mentally to that expression and compute the expectation, you get .676. And so your total payoff is higher if you go west – your expected total payoff is higher if you go west than if you go north. And that’s why the optimal action in this state is to go west.

So that was value iteration. It turns out there are two sort of standard algorithms for computing optimal policies in MDPs. Value iteration is one. As soon as you finish the writing. So value iteration is one and the other sort of standard algorithm for computing optimal policies in MDPs is called policy iteration. And let me – I’m just going to write this down.

Questions & Answers

I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
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Source:  OpenStax, Machine learning. OpenStax CNX. Oct 14, 2013 Download for free at http://cnx.org/content/col11500/1.4
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