L5

Question 1

When a limited number of different alternatives have different outcomes what kind of probability distribution is this

Answer 1

Discrete

Question 2

What is a probability mass function

Answer 2

The function relaying the probability distribution of a discrete random variable

Question 3

If you have a discrete random variable that has an 40% chance of being 2 and 50% chance of being 3 what is the probability of it being 4

Answer 3

10% if that is an option

Question 4

Describe a discrete uniform probability distribution

Answer 4

When every outcome of a defined set has equal likelihood of occurring. Aka classical probability

Question 5

Describe when a probability distribution is binominal

Answer 5

When calculating the likelihood of a number of successes in a given amount of independent trials

Question 6

When is poisson probability distribution used?

Answer 6

When calculating the number of successes occurring in a given time or space

Question 7

What characterizes the hypergeometric probability distribution

Answer 7

A given amount of trials that can result in success or failure but the probability pf success changes across trials

Question 8

Give the two main measures of spread

Answer 8

Variance and standard deviation

Question 9

What is the expected value of a random variable

Answer 9

The mean

Question 10

How would you describe a person who only looks at the average return when making investments, one who pays more for those that vary less and one who accepts loss fir greater variance

Answer 10

Risk neutral, risk averse and risk loving for the gambler

Question 11

What is the mean of a binomial distribution

Answer 11

The number if trials times the probability of success

Question 12

What is the variance if a binomial probability distribution

Answer 12

The number of trials times the probability of failure

Question 13

If you should calculate likelihood of finding a specific number of worms in a plot of land what probability distribution should you use

Answer 13

The Poisson distribution

Question 14

When can you not use the poisson probability distribution

Answer 14

When the successful events are overlapping or negative and if there is different probability on intervals of different size

Question 15

Wich measurement of spread is equal to the mean in poisson random variables

Answer 15

The variance is equal to the mean

Question 16

If you have a bag of good and bad cheese and sequentially pick up a set number of cheezes from the bag which probability distribution should you use to calculate the number of successes in one grab with a set capacity

Answer 16

The hypergeometric probability distribution