I hope you guys don't mind me adding to this and bumping this topic.
Scroll probability can be easily calculated using binomial distribution, in particular, the probability mass formula "![[Image: 68d0ba6ef5dfb8c654702c3290128b10.png]](http://upload.wikimedia.org/math/6/8/d/68d0ba6ef5dfb8c654702c3290128b10.png)
." In this case, P represents the percentage rate (or the percentage the scroll is,) N is number of attempts (or number of slots in equipment) and K is the total number of successes (or landed scrolls.)
The first part (n,k) or n chooses k, is the binomial coefficient, which can be calculated with the formula "![[Image: a12375b9f5661262cf951dc829a33262.png]](http://upload.wikimedia.org/math/a/1/2/a12375b9f5661262cf951dc829a33262.png)
".
Using Excel, I made some basic chart graphics to visualize the probability mass function. The following scenarios are for an overall with 10 slots, using 10%, 30%, 50%, 60% and 70% scrolls.
Success rate (10%)
Success rate (30%)
Success rate (50%)
Success rate (60%)
Success rate (70%)
Point out any errors, if you see any.
Scroll probability can be easily calculated using binomial distribution, in particular, the probability mass formula "
." In this case, P represents the percentage rate (or the percentage the scroll is,) N is number of attempts (or number of slots in equipment) and K is the total number of successes (or landed scrolls.) The first part (n,k) or n chooses k, is the binomial coefficient, which can be calculated with the formula "
". Using Excel, I made some basic chart graphics to visualize the probability mass function. The following scenarios are for an overall with 10 slots, using 10%, 30%, 50%, 60% and 70% scrolls.
Success rate (10%)
| number of successes | percentage rate |
|---|---|
| 0 | 34.87% |
| 1 | 38.74% |
| 2 | 19.37% |
| 3 | 5.74% |
| 4 | 1.12% |
| 5 | 0.15% |
| 6 | 0.01% |
| 7 | 0.00% |
| 8 | 0.00% |
| 9 | 0.00% |
| 10 | 0.00% |
Spoiler
![[Image: pmf10scroll10.jpg]](http://img17.imageshack.us/img17/6898/pmf10scroll10.jpg)
Success rate (30%)
| number of successes | percentage rate |
|---|---|
| 0 | 2.82% |
| 1 | 12.11% |
| 2 | 23.35% |
| 3 | 26.68% |
| 4 | 20.01% |
| 5 | 10.29% |
| 6 | 3.68% |
| 7 | 0.90% |
| 8 | 0.14% |
| 9 | 0.01% |
| 10 | 0.00% |
Spoiler
![[Image: pmf10scroll30.jpg]](http://img713.imageshack.us/img713/2423/pmf10scroll30.jpg)
Success rate (50%)
| number of successes | percentage rate |
|---|---|
| 0 | 0.10% |
| 1 | 0.98% |
| 2 | 4.39% |
| 3 | 11.72% |
| 4 | 20.51% |
| 5 | 24.61% |
| 6 | 20.51% |
| 7 | 11.72% |
| 8 | 4.39% |
| 9 | 0.98% |
| 10 | 0.10% |
Spoiler
![[Image: pmf10scroll50.jpg]](http://img225.imageshack.us/img225/8710/pmf10scroll50.jpg)
Success rate (60%)
| number of successes | percentage rate |
|---|---|
| 0 | 0.01% |
| 1 | 0.16% |
| 2 | 1.06% |
| 3 | 4.25% |
| 4 | 11.15% |
| 5 | 20.07% |
| 6 | 25.08% |
| 7 | 21.50% |
| 8 | 12.09% |
| 9 | 4.03% |
| 10 | 0.60% |
Spoiler
![[Image: pmf10scroll60.jpg]](http://img821.imageshack.us/img821/553/pmf10scroll60.jpg)
Success rate (70%)
| number of successes | percentage rate |
|---|---|
| 0 | 0.00% |
| 1 | 0.01% |
| 2 | 0.14% |
| 3 | 0.90% |
| 4 | 3.68% |
| 5 | 10.29% |
| 6 | 20.01% |
| 7 | 26.68% |
| 8 | 23.35% |
| 9 | 12.11% |
| 10 | 2.82% |
Spoiler
![[Image: pmf10scroll70.jpg]](http://img121.imageshack.us/img121/8213/pmf10scroll70.jpg)
Point out any errors, if you see any.