Standard Deviation and Normal Distribution Flashcard

Front

What does x̄ represent in the formula for standard deviation?

Back

x̄ represents the average of the data set.

Front

In a normal distribution, what percent of information falls within one standard deviation of the mean?

Back

68% of the information falls within one standard deviation of the mean.

Front

What is the standard deviation of scores in a normal distribution where 68% of scores fall between 50 and 80?

Back

The standard deviation is 15.

Front

What does the symbol 'μ' represent in statistics?

Back

μ represents the mean of a data set.

Front

How is standard deviation calculated?

Back

Standard deviation is calculated as the square root of the variance.

Front

What is a normal distribution?

Back

A normal distribution is a probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence.

Front

What is the empirical rule in statistics?

Back

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

Front

If a data set has a mean of 80 and a standard deviation of 5, what range of scores would fall within one standard deviation?

Back

The range of scores would be from 75 to 85.

Front

What is variance in statistics?

Back

Variance is the average of the squared differences from the mean.

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.