Probability Law
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When you say you think something is X to happen, you can be more precise by saying you think it has a probability of X%, where "X" is a number between X and Y.
When you say that you think something is almost no chance to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number greater than 0 up to 10.

For comparison, if you pick a random card from a deck of cards you have an 8% chance of picking a queen.
When you say that you think something is highly unlikely to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number greater than 10 up to 20.

For comparison, if you pick a random letter from the English alphabet you have a 19% chance of picking a vowel.
When you say that you think something is unlikely to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number greater than 20 up to 40.

For comparison, if you play "rock paper scissors" you have a 33% chance of winning.
When you say that you think something is slightly less than an even chance to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number greater than 40 to less that 50.

For comparison, if you play poker you have a 42% chance of getting a pair.
When you say that you think something is an even chance to happen, you can be more precise by saying that you think it's a 50% chance.

For comparison, if you flip a coin you have a 50% chance of getting heads.
When you say that you think something is a slightly better than even chance to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number greater than 50 to less than 60.

For comparison, if you play poker you have a 58% chance of not getting a pair.
When you say that you think something is likely to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number from 60 to less than 80.

For comparison, if you play "rock, paper, scissors" you have a 66% chance of either winning or drawing.
When you say that you think something is highly likely to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number from 80 to less than 90.

For comparison, if you pick a random letter from the English alphabet you have an 81% chance of picking a consonant.
When you say that you think something is almost certain to happen, you can be more precise by saying that you think it's an X% chance, where "X" is a number from 90 to less than 100.

For comparison, if you pick a random card from a deck of cards you have a 92% chance of not picking a queen.
More tips please...
Tip 1: Don't worry if you feel inclined to express your views using a probability that ends in "0" or "5" (like "45%", "60%", "75%" etc). This is a commonly held feeling and while it's great to use the full range of numbers from 0-100, using numbers ending in "0" or "5" already more than doubles the level of detail compared to selecting from the 9 word choices included in this tool.
Tip 2: When you express your views using probabilities, try to pick a point probability within the suggested range, rather than using a range itself. Why? Well, if you say that you think something is a "60-80%" chance, it's impossible to avoid this being interpreted as you implying that you think it's a "70%" chance. So to avoid confusion, try to pick a point probability you feel is most accurate given the evidence that's available to you now.
Tip 3: If you're finding it difficult to use probabilities in complex cases, try to break the case down into smaller component issues. It's much easier to use probabilities for specific issues that are narrowly defined. Plus, when you do this it's easy to find overall chances for the case - check out Tool 2 to see how!
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What happens next?
Sequence probability:
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50
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What happens next?
Sequence probability:
50
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Issue 1
50
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Issue 2
50
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Issue 3
50
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What happens next?
SucceED ON 1, 2 & 3
12.5
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50
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What happens next?
SUCCEED ON 1 & 2, FAIL ON 3
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50
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Issue 3
50
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What happens next?
SUCCEED ON 1 & 3, FAIL ON 2
12.5
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50
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What happens next?
SUCCEED ON 1, FAIL ON 2 & 3
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50
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Issue 2
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Issue 3
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What happens next?
SUCCEED ON 2 & 3, FAIL ON 1
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50
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What happens next?
SUCCEED ON 2, FAIL ON 1 & 3
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Issue 3
50
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What happens next?
SUCCEED ON 3, FAIL ON 1 & 2
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50
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What happens next?
FAIL ON 1, 2 & 3
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