Probability Distributions

Question 1

What are the key aspects of Poisson distribution?

Answer 1

• Discrete data
• Random discrete events over continuous period of time
  e. g. 5 coffees per 30 minutes

λ = the average over the period of time e.g. 2 goals per 30 minutes

Question 2

What are the features of a Discrete Random distribution?

Answer 2

• Discrete data
• Usually given to you in a bar graph
• Asked to calculate expected value and variance

Question 3

What are the features of a Binomial Distribution?

Answer 3

• Discrete data
• Set number of trials
• Two possible outcomes: p and q
• p is the probability of the event happening
• You will be given a probability or a percentage in the question (e.g. 45% of students study NCEA L3 English)

Question 4

What are the features of a Normal Distribution?

Answer 4

• Continuous data mainly; can be discrete with a continuity correction
• Bell shaped
• Symmetrical about the mean
• Mean
• Standard Deviation

Question 5

What are the features of a Uniform Distribution?

Answer 5

• Continuous data
• Maximum
• Minimum
• No other measurements given (e.g. mode)

Question 6

What are the features of a Triangular Distribution?

Answer 6

• Continuous data
• Maximum
• Minimum
• Mode

Question 7

What is discrete data?

Answer 7

Data which can be COUNTED

Question 8

Continuous data

Answer 8

Data which can be MEASURED