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Timing/Effect System Broken on Failures As Well

tbeard1999

SOC-14 1K
In the "dog bites man" dept., the vaunted timing/effect system also yields dubious results in the case of failures.

If the effect die is a 1-2, it's an "abject failure"; 3-4 it's an "average failure"; 5-6 it's a "marginal failure". So here are the odds of rolling the indicated numbers per die:

No Modifiers
1-2: 52%
3-4: 33%
5-6: 14%

-1 Modifier
1-2: 65%
3-4: 27%
5-6: 8%

-2 Modifier
1-2: 77%
3-4: 23%
5-6: 0

So, a character with no modifiers has a staggering 52% chance of an "abject failure" if he fails the task.

Of course, I'm sure that each defender of this system has a fix that completely changes the mechanic, yet really doesn't solve the problem (or introduces new problems at least as bad).

Sigh.
 
Nope, haven't needed it. The very threat of a dropped weapon on a 1 has resulted in more low timing results than I care to mention.
 
tbeard, thanks for your proselatyzing on this topic. I can feel your frustration. Personally, I probably wouldn't have thought about the probabilities until I noticed something was up (which I don't think would have take very long).

For me, it's a broken mechanic and so a show-stopper for MongTrav. However, I will probably still buy it in order to help convert Traveller to the new BRP. :) I have no need for a nostalgic fixation on d6.
 
tbeard, thanks for your proselatyzing on this topic. I can feel your frustration. Personally, I probably wouldn't have thought about the probabilities until I noticed something was up (which I don't think would have take very long).

For me, it's a broken mechanic and so a show-stopper for MongTrav. However, I will probably still buy it in order to help convert Traveller to the new BRP. :) I have no need for a nostalgic fixation on d6.

Well, one can do FAR worse than the BRP system. When's it supposed to be out?
 
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No Modifiers
1-2: 52%
3-4: 33%
5-6: 14%

It is late and I am tired, but could you explain how you arrived at 52%?

1 or 2 on 1D6 is a 2/6 chance = 1/3 = 33%.

If I roll 2D6 and assign the low dice to Effect, then 20 of the 36 permutations should have a 1 or 2 = 55.5%.

... And wouldn't this just indicate that 'most' of the time (>50%), the character will choose not to 'rush and shoot wild' [the basic definition of choosing a better Timing than Effect?]
 
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Well, one can do FAR worse than the BRP system. When's it supposed to be out?

The proof copy has been on sale since before Christmas. The author is submitting his last changes today. Thus, it will be updated and sent off to the printers and then to shops as soon as that whole process takes. Perhaps 1 - 2 months at the most?
 
The proof copy has been on sale since before Christmas. The author is submitting his last changes today. Thus, it will be updated and sent off to the printers and then to shops as soon as that whole process takes. Perhaps 1 - 2 months at the most?

Well, I'll be getting that one. Thanks for letting me know. I've always considered Chaosium's worst mistake to be failing to support Worlds of Wonder. GURPS later proved that the market was ripe for a universal system and the BRP system was as good a system as they come. Oh well, better late than never...
 
Just a rambling thought, I have only read over the T/E system briefly....


A possible fix comes to mind. Instead of allowing the roller to pick which die is timing and which is effect, what would happen if each was assigned to a die? How would this shake up the system?

For example, I need to roll 8+ with +0 DM. I roll a red die (timing) and a white die (effect). I roll a 5 and a 3 (total of 8) for a success. The 5 means I completed the task quicker then average. The 3 means I had a typical success.

Any problems with this change that come to mind? Min/maxing seems to show that this could work: Great rolls (such as double 6's) results in the task being completed as quick as possible with great success (assuming 12 +/- DMs was a success). Poor rolls (such as two 1's) results in the max. possible time taken along with a critical failure (assuming 2 +/- DMs was a failure).

Another min/max would be 1 timing and 6 effect. Depending on DMs, this could result in much time being taken, but with a great success OR max. time being taken while barely failing. A 6 timing with 1 effect would reverse this - really quick with a minimal success or a great failure depending on success of the task.

What problems am I missing? Why couldn't this work as a simple solution?

The change above of course takes away choice from a player (although there are only 2 to choose from anyway) and makes the timing and effect completely randomn. For combat, this takes away an element from initiative. As is, players get to make semi-tactical decisions on how well they complete a task in combat versus what they wish their future initiative to be. Making the timing die completely randomn takes away from the player's ability to fiddle with his initiative by picking from one of two timing dice. Not a huge loss in my opinion, but some may irk at this.
 
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It is late and I am tired, but could you explain how you arrived at 52%?

1 or 2 on 1D6 is a 2/6 chance = 1/3 = 33%.

If I roll 2D6 and assign the low dice to Effect, then 20 of the 36 permutations should have a 1 or 2 = 55.5%.

I think you've just made the same mistake as the designer.

The problem is that a failed roll (or a successful roll) is a subset of the normal 2d6 spread. Therefore, if a roll fails, there is *not* a 1/6 chance of any number appearing on each die. The reason is that many of the higher individual die rolls will result in a success, so they aren't available for a failed roll. The reverse is true with a successful roll.

Assume a no modifiers roll. If the roll fails, it must be a 7-. Here are the 21 possible combinations for 7- on 2d6:

1 1
1 2
1 3
1 4
1 5
1 6
2 1
2 2
2 3
2 4
2 5
3 1
3 2
3 3
3 4
4 1
4 2
4 3
5 1
5 2
6 1

As you can see, you are six times as likely to roll a "1" as a "6".

On either die, 11 of the 21 combinations (52%) are a 1 or 2.

If the lowest die is automatically assigned to the effect die, then a whopping 18 of 21 rolls will be an abject failure.

If the highest die automatically assigned to the effect die, then 3 of the rolls will be an abject failure. But in that case, 18 of the rolls (85%) will yield a very bad timing result (5 or 6).

Since you can't account for specific allocations of timing or effect, I choose to look at the probabilities for each die. Alternatively, you could average the chances of automatically allocating the best die to timing or effect. This will work out to about 50%.

Another way of saying this is that there's a >50% chance of getting a very bad effect or timing result on any miss with no modifiers.

And the stats get weirder as negative modifiers are applied to the effect die. The timing die produces even wierder outcomes if no modifiers are applied:

Failed Rolls
No Modifier:
1-2: 52%
3-4: 33%
5-6: 14%

-1 Modifier
1-2: 46%
3-4: 34%
5-6: 19%

-2 Modifier
1-2: 40%
3-4: 36%
5-6: 23%

Successful Roll
No Modifier:
1-2: 06%
3-4: 33%
5-6: 60%

-1 Modifier
1-2: 0%
3-4: 30%
5-6: 70%

-2 Modifier
1-2: 0%
3-4: 16%
5-6: 84%



So...the worse you are at a task, the faster you tend to do it, whether you succeed or fail.

... And wouldn't this just indicate that 'most' of the time (>50%), the character will choose not to 'rush and shoot wild' [the basic definition of choosing a better Timing than Effect?]

I don't think I understand the question.

The net effect of the T/E system's statistical qualities is:

1. Successes will tend to be exceptional. In other words, exceptional successes will be very common.

2. Failures will tend to be abject failures. In other words, abject failures will be very common.

3. The worse you are at something, the less time it will take you to do it (pass or fail).

4. The effect on the combat system will be to make damage extremely predictable, especially if the player tends to choose the best die for effect (damage). This is true regardless of whether you use the original straight damage rating or the current multiple.

5. The effect of this system on autofire is even worse--poorer troops have very little chance of hitting with autofire, while good troops find it pretty easy to hit automatically with all shots. (Pretty much the exact opposite of what we see in the Real World.)

This does not look like a task roll system I want any part of. And it cannot be fixed. If you move the break points, you just break the system differently. For instance, one idea was to define a "6" as exceptional and a 1-3 as marginal. This change still resulted in exceptional successes occuring far more often than marginal successes. It also meant that an exceptional success would be impossible if the net modifier was a -1. So...no modifier, 33% chance of exceptional success. -1 modifer, 0% chance of exceptional success. Reversing the order of success and failure failed as well (see my previous posts on that), plus it wouldn't work with the combat system.

And since no one brought any of this up until I posted my analysis, I think that the designer failed to do a statistical analysis of the system. I think that he believed that a normal, no modifier roll would produce the same number of exceptional successes as marginal successes. A big mistake.

The problem is that statistical trends like this are hard to identify in just a few games. Hundreds of rolls would need to be tracked before the trend emerges. And I just don't think that Mongoose's playtesters have done this. So at best, you might notice that exceptional results are awfully common. But in the short term, players like that...at least until the NPCs start getting the same benefit.

I'd also add that the MGT system makes it pretty easy to get modifiers of +2 or +3 on most tasks. With a +2 net modifier for effect rolls, there's an 81% chance of each die being a 5+. This means that the player will get at least one effect result of 5+ a whopping 96% of the time.

At the end of the day, the T/E system is an awful lot of trouble for the dubious benefit of producing exceptional successes most of the time.
 
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Just a rambling thought, I have only read over the T/E system briefly....


A possible fix comes to mind. Instead of allowing the roller to pick which die is timing and which is effect, what would happen if each was assigned to a die? How would this shake up the system?

It would result in the statistics that I have quoted. Whether you allow the player to choose the die or whether you allocate the die beforehand, the probabilities don't change. If I were gonna keep the T/E system, I'd let the player choose, at least on failed rolls. Then, the player can occasionally mitigate the asinine results generated by the mechanic.
 
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52% sounds a lot. But it is an analysis of a failure roll. In reality what are the odds of abject failure BEFORE you roll. That is the test of whether a dice system is a problem.

Also what you see is a consequence of using dice to generate a bell curve. If you were using 3d6 and an 18 was a critical success. If you needed 17+ to succeed. That means nearly 1 in 4 of your success rolls will be a critical. But in reality the odds of rolling a critical success remains the same regardless of what degree of success you have, 1 out of 216 possibilities
 
But what's the point of characterizing to what degree a task succeeds or fails if most of your successes will be outstanding successes, and most of your failures will be miserable failures. If you really wanted to randomly determine the T/E of a task, throw another 2D just for T/E.

But then again, why bother? Wouldn't it just be easier to say "you succeeded" or "you failed" and allow the player/ref to role-play the result instead?

Just my cCr2.

-Fox
 
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If you really wanted to randomly determine the T/E of a task, throw another 2D just for T/E.

You know that sounds pretty good. Roll 2d6 for 8+ for success. At the same time roll another 2d6 (coloured and pre-defined which is effect and which is timing). OK, you're rolling 4 dice, but I don't think that will take up too much energy considering all the crisps and softdrink consumed at an average session :)

For my tastes, I'll use 1 & 6 only as exceptional failure/success.
 
Assume a no modifiers roll. If the roll fails, it must be a 7-. Here are the 21 possible combinations for 7- on 2d6
I missed the 7- on 2 dice that ruled out the combinations that added to 8+ and reduced the set from 36 to 21.

PS. I wasn't defending the system, just trying to follow the math to make sure the specific criticism was deserved and not just a case of painting with a broad brush.

Correct me if I am wrong, since I did not read the rules closely ( I don't really care for the general complexity irregardless of the actual mechanics and probability). I thought the whole point of the Timing/Effect Mechanic was that the player chose which die was which after they were rolled so he could choose to be fast and sloppy (high Timing) or slow and careful (high Effect). Obviously, if that were the case, then the fumble would only happen when both die rolled a 1 or 2 - Four of your 21 combinations (19% of all unmodified misses) and 4 of the 36 possible combinations (11% of all unmodified attacks).
 
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I missed the 7- on 2 dice that ruled out the combinations that added to 8+ and reduced the set from 36 to 21.

PS. I wasn't defending the system, just trying to follow the math to make sure the specific criticism was deserved and not just a case of painting with a broad brush.

Correct me if I am wrong, since I did not read the rules closely ( I don't really care for the general complexity irregardless of the actual mechanics and probability).

Me neither. I don't like the system because its fussy; the fact that it's statistically dubious makes me hate it.

I thought the whole point of the Timing/Effect Mechanic was that the player chose which die was which after they were rolled so he could be fast and sloppy (high Timing) or slow and careful (high Effect). Obviously, if that were the case, then the fumble would only happen when both die rolled a 1 or 2 - Four of your 21 combinations (19% of all unmodified misses) and 4 of the 36 possible combinations (11% of all unmodified attacks).

The timing and effect dice are completely separate. So an effect of 1 (abject failure on missed task rolls) can theoretically occur with a timing of 6 (happens really fast). It is not necessary for both dice to be 2- for there to be an abject failure.
 
It would result in the statistics that I have quoted. Whether you allow the player to choose the die or whether you allocate the die beforehand, the probabilities don't change. If I were gonna keep the T/E system, I'd let the player choose, at least on failed rolls. Then, the player can occasionally mitigate the asinine results generated by the mechanic.

If players have the freedom to do this - then what's the problem?

The actual probabilties you are using misses the point that player choice isn't necessarily random. Some may continually choose a Time die fiirst, and some may continually choose the Effect dice first. Some may choose tactically - which is what the intent of the system's design is, surely?

So...the worse you are at a task, the faster you tend to do it, whether you succeed or fail.

Why is this bad as a principle? The worse you are at a task, the quicker you fail.
 
You know that sounds pretty good. Roll 2d6 for 8+ for success. At the same time roll another 2d6 (coloured and pre-defined which is effect and which is timing). OK, you're rolling 4 dice, but I don't think that will take up too much energy considering all the crisps and softdrink consumed at an average session :)

For my tastes, I'll use 1 & 6 only as exceptional failure/success.

Only problem I see is that a very hard task and a very easy task would have the same chance of an exceptional success. Of course the hard task will be harder to succeed, but when it does, it has the exact same chance to be exceptional as a simple task would.

Solution??: Add/subtract the amount you went over or under 8 (the set success number for MongTrav) to your pre-marked T/E dice (can't go below 1 or above 6). Make the player divide this T/E modifier between the T and E dice, so that some of the original intent of Mongoose's mechanic is kept (since choosing T/E dice has been removed).

Example 1: In MogooseTrav I always need an 8+ to succeed. I have a +3 DM for my task. I roll 2D6 for a 2 and a 4. Adding my +3 DM I get a 9 and succeed by +1 over the base 8. I want some more detail, so I look into Timing and Effect. I already pre-marked these dice, the 2 is timing, the 4 is effect. I decide to put my +1 into Effect, bringing it to 5, an exceptional success in Mongoose Trav.

Example 2: I have a -2 DM. I roll a 4 (timing die) and a 2 (effect), with a -2 DM I get a total of only 4, -4 under the 8 I needed. I fail. I must apply -4 to my die for timing and effects. Even if I shove as much as I can into timing (-3 bringing it to minimum of 1), I have to put -1 into effect, making it a critical failure.

Min/Max Example: I'm rolling an Easy task (+4 DM) and have a high skill level (+3 DM) and high attribute (+1 DM) for a total of +8. I only roll a 1 for timing and 2 for effect, but still succeed (3 + 8 = 11) by +3. I'm trying to hurry, but want at least an average effect. I put +1 into effect giving me a 3 (average success). These leaves +2 for timing, bringing it from 1 to 3.

Min/Max Example 2: Using the same example as above, I roll well with a 5 for timing and 5 for effect. My total is 18 or +10 over! I easily use these points to raise both my timing and effect to maximums of 6. I'm so good that I get an exceptional success in record time.

Min/Max Example 3: I only have a skill level of 0 (0 DM) and my attribute is poor (-1 DM) attempting a difficult task (-2 DM). I have a -3 DM so need to roll an 11 or 12 to succeed. I try anyway, rolling about average, 3 timing and 5 effect for a total of 8 - 3 = 5. I fail by -3. I decide to reduce timing to 1, so I must only place -1 towards effect, keeping myself from making a critical failure.

Min/Max Example Notes: If a player is very good at a task, he will often be able to have exceptional succcess and/or complete the task more quickly. This makes sense to me. If a player is bad at a task, he will often take more time and/or have bad failures more often. This also makes sense to me. This seems to be the original intention with the timing and effect of Mongoose.


I know I must have missed some glaring problem, rip away.

Possible issues and notes:

1. How would this affect Mongooses's combat and initiative system?
2. How would this affect the Mongoose rule for attempting multiple tasks at once?
3. How would this affect the current Mongoose autofire rules (one timing die)?
4. Perhaps make the player apply ALL of the +/- modifier to EITHER Timing or Effect?
 
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For anyone who's interested, my fix to T/E is discussed in some depth in this thread on the Mongoose boards: http://www.mongoosepublishing.com/phpBB2/viewtopic.php?t=32532

tbeard considers it a failure, but it resolves all the issues with T/E to my satisfaction, and actually reduces the amount of fiddliness in the sytem (since you no longer need to modify Timing or Effect dice after the roll, simply reading the die faces as they come up).
 
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