Normal Curve Properties
The shape of a normal distribution curve.
What is a bell?
This is the percentage of students at the high school that have a GPA between 2.3 and 3.5. when GPAs are normally distributed with a mean of 2.9 and standard deviation of 0.6.
What is 68%?
This value sits in the middle of a normal curve
What is the mean?
The percent between -1 and 2 on a standard normal curve.
What is 81.86%?
This is the shape we look for on a Normal Quantile (Probability) Plot when checking for Normality.
What is linear?
The total probability of the area under a normal curve
What is 1 or 100%?
This percent of a population sit above the mean
What is 50%?
This is the percentage of a population within one standard deviation of the mean on a normal curve
What is 68%?
This is used for the upper bound when finding the probability greater than a value.
What is 1E99?
This is the visual indicator a data set is not normal when the data is graphed.
What is skewed or not roughly symmetrical?
The Greek letter used to represent mean
What is lowercase mu (μ)?
Above this GPA is the highest 2.5% of the students when GPAs are normally distributed with a mean of 2.9 and standard deviation of 0.6.
What is 4.1?
This is the percentage of a population within three standard deviations of the mean on a normal curve
What is 99.7%?
The percentile for a student that slept 4.5 hours if the mean hours slept is 7.2 and the standard deviation is 1.5.
What is the 3.6th Percentile?
These are the target percentages for standard deviation when checking if a data set is normal.
The Greek letter used to represent standard deviation
What is lowercase sigma (σ)?
This is the percentage of scores are between 600 and 700 for scores on a certain standardized test have a mean of 500 and a standard deviation of 100.
What is 13.5%?
This is the percentage of a population outside of two standard deviations of the mean on a normal curve
What is 5%?
The percentile for a student that slept 9 hours if the mean hours slept is 7.2 and the standard deviation is 1.5.
What is the 88th percentile?
These throw off the measure of center of a data set and make the data set fail normality.
What are outliers?
The total number of standard deviations that accounts for 99.7% of the area under a normal curve.
What are six standard deviations?
The standard deviation of car tires where the mean is 30,000 km and 97.5% the population sits below the value of 34,000 km.
What is a standard deviation of 2000km?
The percentage of a population that falls between one and two standard deviations above or below the mean on a normal curve
What is 27%?
This is the probability that a value falls above 2.5 and below -2.5 on a standard normal curve.
What is 1.24% or 0.0124?
The answer to whether this data set is normal: 22, 16, 7, 19, 15, 22, 20, 21, 14, 23, 16, 18, 23, 10, 1
What is no?