Talk:Fall 2015 Event/@comment-26095489-20151203094930

Just drop this graph here if you are interested in probability or just want to show off your math skill =P. First thing first, this graph does not represent that when will you get your drops as each S rank drop rate is independently uneffected by previous drop. Which mean after you had 500 S-rank with no rare drop, the next S rank drop rate will be the same drop rate as anyone else at anytime.

Using the basic formula:pq^(y-1), p= probability to drop, q=1-p, y=numbers of attemp with S rank.

First, Assumption made by following averange drop rate from poi data as the actual drop rate of rare ship. Graf(1.651%), U-511(0.404%), Prinz(1.103%), Akizuki(1.138%), Arashi(2.499%)

Example for first try lucky bastard that get Prinz= (0.01103)*(1-0.01103)^(1-1) = 0.01103 = 1.138% TTKs here will get her in their 1 try.

Example for those who get her in secound try=  (0.01103)*(1-0.01103)^(2-1) = 0.010908 = 1.091% TTKs here will get her in their 2nd try.

Hence percentage of TTKs will get Prinz in 2 S rank = % 1st try + % 2nd try =  1.138% +  1.091% = 2.229% TTKs here will get her with 2 S-rank

And the list go on with the % 3 try TTK until the graph below is form, Thanks spreadsheet.

So what's the use of the graph for?

For example: I got Graf in 25 S-rank, and the graph correspond in y-axis is 34%. Which mean there is approximate one third of the TTKs here would got her in their 25 try and 2/3 TTKs here won't.

Then there is estimation that one in every ten (10%) TTKs here would not get Prinz after 208 S rank or 1/100 (1%) TTKs here would not get Prinz after 415 S rank.

Hence, for those lucky TTKs, be grateful for the drop and for those unlucky TTKs, just take the game easy and don't feel bad of it.

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