Module 17: Statistics

Question 1

How to calculate probability?

Answer 1

P(E)= r/n
r is total number possible outcomes
n is number of all possible outcomes

Question 2

Probability = 1 equation?

Answer 2

P(E) + P(not E) = 1
Rearrange
P(E) = 1-P(not E)
P(not E) = 1-P(E)

Question 3

What do we need to decide in order to apply the addition rule?

Answer 3

If A and B are mutually exclusive or not

Mutually exclusive means can’t both happen at once

Question 4

If both events ARE mutually exclusive what is the probability of either event happening?

Answer 4

P(A or B)= P(AB) + P(B)

Question 5

If events are NOT mutually exclusive what is the probability of whether A or B occurs?

Answer 5

P(A or B) = P(A) + P(B) - P(A and B)

Question 6

What do we use if we want to know the probability of event A AND B both occurring?

Answer 6

Multiplication rule

Question 7

A and B if events are independent?

Answer 7

P (A and B) = P(A) x P(B)

Question 8

A and B if dependant on one another?

Answer 8

P (A and B) = P(A) x P(B given that A has already happened)

Question 9

If event is independent?

Answer 9

One occurring has no effect on the other

Question 10

If event is dependant?

Answer 10

One has to occur to allow other to occur

Question 11

If given info regarding whether two events are mutually exclusive or not you can rearrange the addition rule how to find P(A and B)

Answer 11

P(A or B) = P(A) + P(B) - P(A and B)

Question 12

What is the random variable?

Answer 12

Something we are trying to estimate the probability of

Question 13

What is a discrete random variable?

Answer 13

Something that can only take specific values can ‘count’

e.g. cars in parking lot, can’t have decimal

Question 14

What is a continuous random variable?

Answer 14

Can take any value, have to ‘measure’ e.g. temperature

Question 15

What are the criteria for binomial distribution?

Answer 15

n identical trials
each results in one of two possible outcomes
Independent
Interested in number of successes

Question 16

What is n, p and x in binomial distribution?

Answer 16

n = number of trials e.g. 4
p = probability of success
x = events, number of successes (e.g. 0,1,2,3,4)

Question 17

Features for Poisson distribution?

Answer 17

Discrete random variable

How many TIMES and event occurs

Question 18

What are the 4 key aspects of Big Data?

Answer 18

Volume
Velocity- speed
Variety
Veracity- reliability

Question 19

Confidence equation?

Answer 19

X = x̄ + or - Z(o/route of n)