Standard 11 Checkpoint

Front

What is the mean in a normal distribution?

Back

The mean is the average value of a set of data points, representing the center of the distribution.

Front

What is standard deviation?

Back

Standard deviation is a measure of the amount of variation or dispersion in a set of values.

Front

What does it mean if data is normally distributed?

Back

Data is normally distributed if it follows a bell-shaped curve, where most of the observations cluster around the central peak and probabilities for values further away from the mean taper off symmetrically.

Front

How do you calculate the z-score?

Back

Z-score = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.

Front

What is the significance of the z-score in statistics?

Back

The z-score indicates how many standard deviations an element is from the mean, helping to understand the position of a value within a distribution.

Front

What is the empirical rule in statistics?

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, and 99.7% within three.

Front

How do you find the proportion of data above a certain value in a normal distribution?

Back

You can find the proportion by calculating the z-score for that value and then using the standard normal distribution table to find the corresponding probability.

Front

What is the purpose of using a normal distribution in statistics?

Back

Normal distribution is used to model real-valued random variables whose distributions are not known, allowing for easier analysis and interpretation.

Front

What does it mean to find the percentile of a score?

Back

Finding the percentile of a score indicates the percentage of scores that fall below that score in a distribution.

Front

How do you interpret a standard deviation of 1.4 inches in the context of waist sizes?

Back

A standard deviation of 1.4 inches means that most waist sizes will fall within 1.4 inches above or below the mean waist size of 29 inches.