AP Statistics Notes: Unit 6

Sampling Distribution (Parameters & Statistics):

• Sample mean x^

• Sample proportion p^

• Population mean 𝝁

• Population proportion p

⭐️As n increases, the spread decreases and the sampling distribution of p becomes approximately Normal  

Always Identify:

• Parameter (what we are trying to find)

• Population (what group you’re doing research on)

• Sample (selected amount of the population)

• Statistic (a numerical value that represents a data point of the sample)

Distributions of Sample Data:

• The population distribution

• The distributions of sample data

• The sampling distribution

  

Sampling Distribution of a Sampling Porportion:

• Mean(p^)=P

• Standard Deviation: squareroot p(1-p)/n

• 10% Rule: np ≥ 10%of n and n(1-p)≥10% of n (if both are correct, distrubution is approximately normal)

⭐️Biased=unequal and unbiased=equal