# Stats Key Facts Knowledge

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• Created by: EmiLy1703
• Created on: 13-04-17 11:27
Define an event
One or more possible outcomes
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Define sample space
A list of all possible outcomes
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P(A or B) = P(A) + P(B) - P(A and B)
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What are independent events?
Events that don't impact on each other
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How would you prove that events are independent? (2 ways)
Given that rule or P(A and B) = P(A) x P(B)
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What are mutually exclusive events?
Two things that can't happen at the same time
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Show two ways of mutually exclusive events
Sample space or P(A and B) = 0
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Write down the given that rule
P(A given B) = P(A and B) divided by P(B)
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Which other chapters does maths from chapter 5 crop up?
Chapter 9
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What does PMCC mean and what does it show?
PMCC = product moment correlation coefficient. It shows if there is a strong positive or negative correlation
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What is the PMCC range and what do the numbers mean?
Range from -1 to 1 showing strong positive or negative correlation
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How does coding affect PMCC?
Coding doesn't affect PMCC
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When is regression anaylis appropriate?
Only when there is a significant form of correlation
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The independent variable should be on which axis...
X axis
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Explain what is meant by extrapolation and interpolation and comment on their reliability
Extrapolation - predictions outside of the data range, unreliable. Interpolation - within the data range, reliable
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Why would coding be used in regression anaylsis and what would the impact of coding be?
Convert a large value
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How do you find expectation of x?
Value multiplied by probability of occuring and then add them together
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How do you find the variance of x?
Value squared multiplied by probability of occuring and then - mean squared
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For a fair regular die, write down a probability distribution and a probability function
Distribution all outcomes have 1/6 of a chance. Function P(X=x) 1/6 x=1, 2, 3, 4, 5, 6
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What does the letter F relate to in regards to probability function or distribution?
F stand for cumulative
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How does coding affect expectation?
Does as expected
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How does coding affect variance?
Adding doesn't affect, multiplying = value squared
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## Other cards in this set

### Card 2

#### Front

Define sample space

#### Back

A list of all possible outcomes

### Card 3

#### Back ### Card 4

#### Front

What are independent events?

#### Back ### Card 5

#### Front

How would you prove that events are independent? (2 ways)

#### Back 