Statistics Chapter 3
percentile
each of the 100 equal groups into which a population can be divided according to the distribution of values of a particular variable.
Chebyshev's Theorem
he rule is often called Chebyshev's theorem, about the range of standard deviations around the mean, in statistics. The inequality has great utility because it can be applied to any probability distribution in which the mean and variance are defined.
Property of Median UPPER OR LOWER
median is used to find out if the data value falls in the upper or lower half of the distribution
Sample
sample is a set of data collected and/or selected from a statistical population by a defined procedure. ... Typically, the population is very large, making a census or a complete enumeration of all the values in the population is either impractical or impossible.
Symmetric
If the data are symmetric, they have about the same shape on either side of the middle. In other words, if you fold the histogram in half, it looks about the same on both sides
five-number summary
The five-number summary is a set of descriptive statistics that provide information about a dataset. It consists of the five most important sample percentiles: the sample minimum (smallest observation) the lower quartile or first quartile. the median (middle value)
Property of Mean OUTLIERS
The mean is affected greatly by extremely high of low values called outliers.
Property of Mean ALL VALUES
The mean is found by using all the values of the data set
Property of Mean UNIQUE
The mean of a data set is unique
Property of Median OPEN ENDED
The median can be used in frequency distributions
Property of Median OUTLIERS
The median is not affected very much by outliers
Property of Median CENTER
The median is used to find the center of middle value or the data set
Property of Midrange MIDPOINT
The midrange gives the midpoint of the range of the data set
Property of Midrange OUTLIERS
The midrange is affected by outliers
Property of Midrange EASY
The midrange is easy to compute
Property of Mode NOMINAL
The mode can be used for nominal and categorical variables
Property of Mode UNIQUE
The mode is not necessarily unique and may not even exist
Property of Mode EASIEST
The mode is the easiest average to find
Property of Mode TYPICAL
The mode is used to find the most typical case
Bimodal
a bimodal distribution is a continuous probability distribution with two different modes.
Left Skew
A "skewed left" distribution is one in which the tail is on the left side.
Right Skew
A "skewed right" distribution is one in which the tail is on the right side
boxplot
A box plot is a graphical rendition of statistical data based on the minimum, first quartile, median, third quartile, and maximum. The term "box plot" comes from the fact that the graph looks like a rectangle with lines extending from the top and bottom.
Population
Population is the entire pool from which a statistical sample is drawn. The information obtained from the sample allows statisticians to develop hypotheses about the larger population.
Property of Mean OPEN ENDED
To find the mean of a frequency distribution , there must not be an open-ended class
parameter
is a measurable characteristic of a population, such as a mean or a standard deviation
outlier
is a point which falls more than 1.5 times the interquartile range above the third quartile or below the first quartile.
decile
is any of the nine values that divide the sorted data into ten equal parts, so that each part represents 1/10 of the sample or population.
empirical rule
states that for a normal distribution, nearly all of the data will fall within three standard deviations of the mean.
coefficient of variable
the coefficient of variation (CV), also known as relative standard deviation (RSD), is a standardized measure of dispersion of a probability distribution or frequency distribution.
