7.4 - Lesson Flashcard Recovery

Front

What is standard deviation?

Back

Standard deviation is a measure of the amount of variation or dispersion in a set of values. A low standard deviation indicates that the values tend to be close to the mean, while a high standard deviation indicates that the values are spread out over a wider range.

Front

How do you find the standard deviation of a data set?

Back

To find the standard deviation, follow these steps: 1. Calculate the mean of the data set. 2. Subtract the mean from each data point and square the result. 3. Find the average of these squared differences. 4. Take the square root of this average.

Front

What does a lower standard deviation indicate about a data set?

Back

A lower standard deviation indicates that the data points are closer to the mean, suggesting less variability and more consistency in the data.

Front

What does a higher standard deviation indicate about a data set?

Back

A higher standard deviation indicates that the data points are spread out over a wider range of values, suggesting greater variability and less consistency in the data.

Front

If Company A has a mean of 90 and a standard deviation of 20, and Company B has a mean of 75 and a standard deviation of 30, which company has less variation?

Back

Company A has less variation because it has a lower standard deviation (20) compared to Company B (30).

Front

What is the median in a data set?

Back

The median is the middle value when a data set 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

How can you compare the centers and spreads of two data sets?

Back

To compare centers, look at the means or medians. To compare spreads, look at the range or standard deviations. A higher median indicates a higher center, and a wider spread indicates more variability.

Front

What is the relationship between mean and standard deviation?

Back

The mean provides a measure of central tendency, while the standard deviation measures the spread of the data around the mean. Both are important for understanding the distribution of data.

Front

If all sets have the same mean, which set has the points closest to the mean?

Back

The set with the lowest standard deviation has the points closest to the mean, as it indicates less variability.

Front

What is the formula for standard deviation?

Back

The formula for standard deviation (σ) is: σ = √(Σ(xi - μ)² / N), where μ is the mean, xi represents each data point, and N is the number of data points.