Card Set Information
collection of persons, items, or interests
Where researches gather data from whole populatin for a given measurement of interest
portion of the whole and if properly take, is rep of the whole
business analyst is usin data gathered on a group to describe or reach conclusions about that same group.
researhers gather data from a sample and uses the stats generated to reach conclusion about the population from which the sample was taken
descriptive measure of the population.Greek letters
lowest level of measurement
representing nominal level data used to classify or categorize
measure is higher than nominal. RANK
measure next to the higest level of data in which the distancecs between consecutive numbers have meaning and the data are always numerical.
height, weight, time, volume
require data to be interval or ration.
analyze interval or ratio data.
Raw data, or date that have not been summarized in any way
data been organized into a frequency distribution.
summary of data presented in the form of class intervals and frequencies.
difference between the largest and smallest number
midpont of each class interval
halfway acoss the class interval and be calculated as the average of the class endpoints.
proportion of the total frequency that isw any given class interval in a frequency distribution.
Individul class frequency divided by the total frequency.
a running total of grequencies through the classes of a frequency distribution.
is a series of contiguous bars or rectangles that rep the frequency of data given class intervals.
ploted as a dot at the class idpoint and the dots are connected by a series of line segments.
cumulative frequency polygon
display continuous , quatative data/
Steam and Leaf Plot
seperating the digits are the stem and consist of the higher value digits
a circular depiction of data where the area of the whole pie represents 100% of the data and slices of the pie represent and a percentage breakdown of the sublevels.
Bargraph Bar chart
use this tally to produce a vertical bar chart that displays the most common tyesps of defects, ranked in order of occurence from left to right.
two dimesional graph plot of pairs of points from numerical variables
measure of central tendency
yield info about the center, middle part or group of numbers
the most frequently occuring value in a set
the case of a tie for most frequently, occurring number.
Data sets with more than two modes
the average of a groupe of numbersand is computed by summing all numbers and dividing the number of numbers.
measure of varaiablity
describe the spread of the dispersion of a set data.Using measures of varability in conjunction with measures of central tendency makes possible a more complete numerical description of the data
range of values between the first and third quartile.
deviation from the mean
subtracting the mean from each value of data yields
mean absolute deviation
average of the absolute values of the deviations around the mean for a set numbers
average of the squared deviations about the arthmetic mean for a set of numbers.
sum of squares of x
sum of the squared deviations about the mean of a set of values
square root of variance
Two ways of applying standard deviation
is computed by summing the data values and dividing the number of values
distribution is asymmetrical or lacks symmetry
describe the amount of peakedness of a distribution.
distributions that are thin and high
distributions that are flat and spread out
box and whisker
diagram that utilizes the upper and lower quartiles along with the median and the two most extreme values to depict a distribution graphically.
determined prior to the experiment
classical method of assigning probablities
a process that produces outcomes, and an event, which is an outcomes of an experiment.
relative frequency of occurence method
the probablity of an event occuring is equal to the number of times the ven has occurred in the past divided by the total number of opportunites for the event have occurred
assigning probality based onm the feelings inisghts determing the probablity
a process that produces outcomes
outcome of an experiment
events that cannot be decomposed or broken down
contains the elements common to both sets
occurrence or nonoccurrence of one of the events does not affect the occurrence or nonoccurrence of the other event
elementary events of an experiment not in A comprise its complement
mn couting rule
marginal, union, joint, and conditional