Statistics Review

Front

What is the median in a data set?

Back

The median is the middle value of a data set when it is ordered from least to greatest. If there is an even number of observations, the median is the average of the two middle numbers.

Front

What does interquartile range (IQR) measure?

Back

The interquartile range (IQR) measures the spread of the middle 50% of a data set. It is calculated as the difference between the third quartile (Q3) and the first quartile (Q1).

Front

How do you calculate the margin of error?

Back

The margin of error is calculated by taking the critical value (z-score) multiplied by the standard deviation divided by the square root of the sample size.

Front

What is a box plot?

Back

A box plot is a graphical representation of a data set that displays the median, quartiles, and potential outliers. It provides a visual summary of the distribution.

Front

What does it mean if data is skewed right?

Back

If data is skewed right, it means that the tail on the right side of the distribution is longer or fatter than the left side, indicating that there are a few high values.

Front

What is the Empirical Rule?

Back

The Empirical Rule states that for a normal distribution, approximately 68% of the data falls within one standard deviation of the mean, 95% within two standard deviations, and 99.7% within three standard deviations.

Front

What is a histogram?

Back

A histogram is a graphical representation of the distribution of numerical data, showing the frequency of data points within specified ranges (bins).

Front

What does it mean for data to be symmetrically distributed?

Back

Data is symmetrically distributed when the left and right sides of the distribution are mirror images of each other, indicating that the mean, median, and mode are all equal.

Front

How do you find the true mean from a sample?

Back

The true mean can be estimated from a sample by calculating the sample mean and considering the margin of error to create a confidence interval.

Front

What is a confidence interval?

Back

A confidence interval is a range of values, derived from a data set, that is likely to contain the true population parameter with a specified level of confidence.