Shapes of Distribution
variables
characteristics (information about the cases)
Skewed Left
data is shifted toward the lower numbers.
Symmetry
distribution of data that have the same shape on both sides of the center.
maximum
highest number
median
middle number in order of the data
Cluster
several data points that lie close together within a small interval
mean < median
skewed left
mean > median
skewed right
mean = median = mode
symmetric
outilers
the numbers that lie away from others
Histogram
A graph that uses bars to show the frequency of equal ranges or groups of data.
mean
A measure of center in a set of numerical data, computed by adding the values in a list and then dividing by the number of values in the list.
Skewed Right
data is shifted toward the higher numbers.
Q3
top 25%
bimodal
two modes in the set of data
median
A measure of center in a set of numerical data - the value appearing at the center of a sorted version of the list - or the mean of the two central values if the list contains an even number of values.
Density curve
Area under = 1; above the x-axis
Gap
a larger space between sets of data values.
minimum
lowest numbr
range
Difference between the largest and smallest values that occur in a set of data.
cases
The subjects (or objects) of statistical examination.
mode
The value that occurs most frequently in a given data set.
Center, Shape and Spread
When you are asked to describe a set of data what should you always include?
Outlier
a number that is very different from the rest of the data set.
Q1
bottom 25%