Symbols
What is the symbol for sample standard deviation?
s
This is the average of a data set.
Mean
This is the square root of the variance.
Standard Deviation
This is the lowest value in a data set.
Minimum
This theorem can be used to estimate the minimum percentage of data within a certain number of standard deviations from the mean, regardless of the data's distribution.
Chebyshev's Theorem
What is the symbol for population standard deviation?
Sigma
This is the middle value of an ordered data set.
Median
A low value for this statistic indicates that data points are clustered closely around the mean.
Standard Deviation
This value marks the 75th percentile of a data set.
Q3
Q3-Q1
X Bar
This is the value that appears most frequently in a data set.
Mode
Why is it important to know the difference between sample and population standard deviation?
Different formulas cause different answers.
In a box plot, the box itself represents this percentage of the data.
Middle 50%
Using Chebyshev's, if a data set has a mean of 50 and a standard deviation of 10, at least 88.9% of the data falls between these two values.
What is the symbol for population mean?
Mu
This is a type of mean that removes a certain percentage of the highest and lowest values before calculating the average.
Trimmed Mean
The number of hours a group of friends spent exercising last week: 3, 5, 2, 6, 4. Find the sample standard deviation and variance for this data set.
Standard deviation: 1.58
Variance: 2.5
The line inside the box of a box plot represents this value
Median
What percentage is used for Chebyshev's Theorem when you are finding values 4 standard deviations from the mean?
93.8%
What is the symbol for population mean in the Ti-84?
X Bar
This type of average is used when some data points contribute more than others, such as in calculating a final grade.
Weighted Average
A list of scores on a math test: 92, 88, 75, 95, 80. Find the population standard deviation and variance for this data set.
Standard Deviation: 7.46
Variance: 55.6
This type of graph displays the five-number summary.
Box and Whisker Plot
What is the relationship between variance and standard deviation?
Variance is standard deviation squared OR standard deviation is the square root of variance.