What is the purpose of inferential statistics?
To use sample data to draw conclusions, make estimates, and test hypotheses about a population while quantifying uncertainty using probability.
What percentage of scores are within one standard deviation and two standard deviations of the mean for a standard normal curve (Z score distribution)?
About 68% of scores fall within ±1 standard deviation of the mean, and about 95% fall within ±2 standard deviations.
Using the normal curve table in the appendix of your textbook, what Z score is associated with 3.01% of the area beyond that Z score?
A Z score of approximately 1.88 leaves 3.01% (0.0301) of the distribution in the upper tail beyond the score.
Using the normal curve table in the appendix of your text, what column is used to determine the area between the mean and a Z score for a normal curve?
The table body (probability values) is used, located at the intersection of the Z score row and column; the columns represent the hundredths place of the Z score.
What is the difference between a sample and a population?
A population includes all members of a defined group of interest, while a sample is a subset of that population selected for measurement and analysis.
What is the mathematical definition of probability?
Probability is the numerical measure of the likelihood of an event, defined mathematically as the number of favorable outcomes divided by the total number of possible outcomes (for equally likely outcomes), ranging from 0 to 1.
