Statistical Concepts and Data Analysis Review

Front

What is a skewed left distribution?

Back

A distribution where the left tail is longer or fatter than the right tail, indicating that most data points are concentrated on the right.

Front

What is a skewed right distribution?

Back

A distribution where the right tail is longer or fatter than the left tail, indicating that most data points are concentrated on the left.

Front

What does it mean to score at the 55th percentile?

Back

It means that 55% of the class scored the same or worse than you did.

Front

What is a z-score?

Back

A z-score indicates how many standard deviations an element is from the mean.

Front

What is the z-score for a value that is 2 standard deviations below the mean?

Back

-2.00

Front

In a normal distribution, what percent of scores fall within one standard deviation of the mean?

Back

Approximately 68%.

Front

What is the mean (μ) in a normal distribution?

Back

The average of all data points in the distribution.

Front

What is the standard deviation (σ) in a normal distribution?

Back

A measure of the amount of variation or dispersion of a set of values.

Front

How do you calculate the percentile rank of a score?

Back

Percentile rank = (number of scores below the score / total number of scores) x 100.

Front

What is the empirical rule in statistics?

Back

In a normal distribution, about 68% of data falls within one standard deviation, 95% within two, and 99.7% within three standard deviations.