MC: Estimation & Interference Flashcards
(14 cards)
Define sample error
Sample error is the difference between a sample statistic, and the true population parameter
The larger the size of n, the closer the sample mean will be to_____.
The population mean
Example of sample mean versus population mean.
Dispersion of sample means around the population mean is denoted by ____.
Variance/ N
The standard deviation of the distribution of sample means , X bar, is called ______.
the standard error of the sample mean
What is the standard error of the same mean equation?
When would you use the sample standard deviation in calculation of Standard error?
When population standard deviation isn’t known.
As sample size increases, the standard error will _____.
Decrease
What is the difference between standard deviation and standard error?
Standard deviation is the dispersion of a SINGLE observation from a distribution.
Standard error is the dispersion of the SAMPLE MEANS around around the distributions TRUE POPULATION MEAN.
What is the confidence intervals formula?
What are the 3 properties of the “Student’s T” distribution?
- Symmetrical
- Fatter tails than normal distribution
- Defined by single parameter, degrees of freedom (df = n-1)
When do you use the students t distribution?
When population std isn’t known, use sample std in the standard error calculation.
Sample mean follows the student’s t distribution instead of a _____.
Normal distribution
When calculating confidence intervals look for…..
