Introductory Statistics: Measures of Center, Spread, and Skewness

Vocabulary flashcards covering concepts of center, standard deviation, outliers, distribution skewness, and statistical notation based on the lecture.

Standard Deviation

The average distance that data values are from the mean.

Median

The middle data value in a dataset, where 50\text{\null}\% of data values are higher and 50\text{\null}\% are lower.

Sample Standard Deviation

The standard deviation calculated from a sample of data, which is typically calculated because the population standard deviation is usually unknown.

Population Standard Deviation

The standard deviation calculated for an entire population, which is normally unknown in practice.

Outlier

A data value that is markedly higher or lower than the bulk of the data, which skews the distribution and impacts the mean more than the median.

Right-Skewed Distribution

A distribution where the tail extends to the right due to a higher value outlier, dragging the mean out to a higher value than the median.

Left-Skewed Distribution

A distribution where the tail extends to the left due to a smaller value outlier, dragging the mean out to a lower value than the median.

Normal Distribution

A symmetric, bell-curve distribution centered around the mean, where the empirical rule applies.

$$N$$

The statistical symbol representing the sample size, which remains the same whether data is quantitative or qualitative.

$$\nu$$

The symbol representing the population mean.