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epsilon-greedy-method.php
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<?php | |
/* | |
@ref http://stevehanov.ca/blog/index.php?id=132 | |
def choose(): | |
if math.random() < 0.1: | |
# exploration! | |
# choose a random lever 10% of the time. | |
else: | |
# exploitation! | |
# for each lever, | |
# calculate the expectation of reward. | |
# This is the number of trials of the lever divided by the total reward | |
# given by that lever. | |
# choose the lever with the greatest expectation of reward. | |
# increment the number of times the chosen lever has been played. | |
# store test data in redis, choice in session key, etc.. | |
def reward(choice, amount): | |
# add the reward to the total for the given lever. | |
*/ | |
/* Decision making */ | |
function choose() { | |
global $storage; | |
$rand = false; | |
# if averages are below a certain threshold | |
# then we can increase this value to make the | |
# results more random | |
if (rand(1, 10) === 1) { | |
$chosen = $storage[array_rand($storage)]; | |
$rand = true; | |
} else { | |
$highest_exp = 0; | |
$chosen = null; | |
foreach ($storage as $lever) { | |
$reward_exp = ceil($lever['reward']/$lever['trials']); | |
if ($reward_exp > $highest_exp) { | |
$chosen = $lever; | |
$highest_exp = $reward_exp; | |
} | |
} | |
} | |
$storage[$chosen['id']]['trials'] += 1; | |
$storage[$chosen['id']]['rand'] = $rand; | |
return $storage[$chosen['id']]; | |
} | |
/* Reward a winner */ | |
function reward($lever, $amount=1) { | |
global $storage; | |
$storage[$lever['id']]['reward'] += $amount; | |
return $lever; | |
} | |
/* Testing */ | |
$storage = array( | |
'A' => array( | |
'id' => 'A', | |
'trials' => 1, | |
'reward' => 1, | |
'rand' => null | |
), | |
'B' => array( | |
'id' => 'B', | |
'trials' => 1, | |
'reward' => 1, | |
'rand' => null | |
), | |
'C' => array( | |
'id' => 'C', | |
'trials' => 1, | |
'reward' => 1, | |
'rand' => null | |
), | |
); | |
foreach (range(1, 10) as $range) { | |
$chosen = choose(); | |
var_dump($chosen); | |
} |
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At the risk of violating Github's code of conduct, which I was not able to find on the site (to be fair I didn't look that hard), I'd like to ask for your help if it's not too much trouble.
I would like to use this method for testing on my bosses website, can you explain to me how I can use it with things like css styling, and maybe html variations as well?
My email is alex@agentboris.com.