PBSI 245 EXAM 4 REVIEW QUESTIONS WITH
VERIFIED ACCURATE ANSWERS
Parameter - Answers -numbers that describe a population
Statistic - Answers -estimates that describe a population
Sampling distribution - Answers -distribution of values taken by a statistic
Statistical inference - Answers -conclusions about a population based on data from a
sample
Confidence interval (CI%) - Answers -true population parameter within a interval;
calculated from sample data
Purpose of a confidence interval - Answers -to estimate the proportion p of the
individuals in a population who have the same characteristic
What are confidence intervals impacted by? - Answers -estimate and margin of error
What are the parts of a confidence interval formula? - Answers -1. An interval around
the parameter; calculated from data
2. A confidence level "C": probability that the interval will capture the true parameter
value in repeated samples
Confidence level vs. Confidence interval - Answers -level: confidence (frequency) that
the interval has the parameter
Interval: values in an interval that capture parameter (numbers)
Margin of error - Answers -how much error around the estimate is acceptable (ex: 2
sds)
Standard error - Answers -standard deviation of the sampling distribution of a sample
statistic (many individual statistics)
P-hat - Answers -sample portion of characteristic
X-bar - Answers -sample mean
Mu - Answers -population mean
With more observations... - Answers -less variable, more normal
VERIFIED ACCURATE ANSWERS
Parameter - Answers -numbers that describe a population
Statistic - Answers -estimates that describe a population
Sampling distribution - Answers -distribution of values taken by a statistic
Statistical inference - Answers -conclusions about a population based on data from a
sample
Confidence interval (CI%) - Answers -true population parameter within a interval;
calculated from sample data
Purpose of a confidence interval - Answers -to estimate the proportion p of the
individuals in a population who have the same characteristic
What are confidence intervals impacted by? - Answers -estimate and margin of error
What are the parts of a confidence interval formula? - Answers -1. An interval around
the parameter; calculated from data
2. A confidence level "C": probability that the interval will capture the true parameter
value in repeated samples
Confidence level vs. Confidence interval - Answers -level: confidence (frequency) that
the interval has the parameter
Interval: values in an interval that capture parameter (numbers)
Margin of error - Answers -how much error around the estimate is acceptable (ex: 2
sds)
Standard error - Answers -standard deviation of the sampling distribution of a sample
statistic (many individual statistics)
P-hat - Answers -sample portion of characteristic
X-bar - Answers -sample mean
Mu - Answers -population mean
With more observations... - Answers -less variable, more normal
