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QBA Exam 1
chapters 1-6
44
Other
Undergraduate 2
09/22/2009

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Term
two categories of categorical data
Definition
nominal and ordinal (above avg. avg. below avg., like eye color, male or female)
Term
two categories of quantitative data
Definition
discrete and continuous
Term
what is a simple random sample
Definition
equally likely chance to occur
Term
what is clustered data
Definition
randomly select groups from random groups
Term
what is stratified data
Definition
random picked from homogeneous data
Term
what is bias
Definition
mistake on our part, swayed toward one side
Term
what is sampling error
Definition
always present, can not be avoided
Term
what is a contingency table good for
Definition
reading 2 way frequencies
Term
what are pie charts and bar charts good for
Definition
what %, how many, marginal/conditional distributions
Term
what is a histogram used for
Definition
to see distribution shape
Term
what are the distribution shapes
Definition
symmetrical, skewed right, skewed left
Term
what is shown in a box plot
Definition
first and third quartiles, fences, median, and outliers
Term
what is a time series used for
Definition
to see a trend over time
Term
how do you determine the central location
Definition
mean, median, and mode
Term
how do you find variation
Definition
range, IQR (Q3-Q1), variance, standard deviation, and z scores
Term
how do you find the z score
Definition
value of interest-median/standard deviation
Term
probability rule: probability must always be between ____ and ____
Definition
0 and 1
Term
probability rule: grand total must not be over
Definition
1
Term
when do you use the addition rule
Definition
OR or BOTH
Term
under what conditions do you use the addition rule if it says OR or BOTH
Definition
they must be mutually exclusive (disjoint), they can not happen at the same time
Term
when do you use the multiplication rule
Definition
AND
Term
under what circumstances do you use the multiplication rule when it says AND
Definition
it can only happen if A and B are independent (does not influence the other)
Term
when do you use the complement rule
Definition
AT LEAST
Term
how do you find the complement rule
Definition
1- prob of not getting anything
Term
individuals who answer the survey are referred to as
Definition
respondents
Term
people whom we experiment on are
Definition
subjects or participants
Term
animals, plants, website, and other inanimate subjects are often called
Definition
experimental units
Term
the characteristics recorded about each individual or case are called
Definition
variables
Term
in a ____________ two or more seperate data tables are linked together so that information can be merged across them.
Definition
relational database
Term
when a variable names categories and answers questions about how cases fall into those categories we call it a
Definition
categorical variable
Term
when a variable has measured numerical values with units and the variable tells us about the quantity of what is measured, we call it a
Definition
quantitative variable
Term
categorical variables used only to name categories are sometimes called
Definition
nominal variables
Term
values that can be individually ordered are
Definition
ordinal values
Term
what is a time series
Definition
we have the same variable measured at regular intervals over time
Term
what is cross-sectional data
Definition
where several variables are measured at the same time point.
Term
What you must know to analyze data
Definition
WHO, WHAT, and WHY
Term
census
Definition
an attempt to collect data on the entire population of interest
Term
parameter
Definition
a numerically valued attribute of a model for a population.
Term
population
Definition
the entire group of individuals or instances about whom we hope to learn
Term
sampling frame
Definition
a list of individuals from which the sample is drawn.
Term
bimodal
Definition
distributions with two modes
Term
histograms
Definition
uses adjacent bars to show the distribution of values in a quantitative variable
Term
spread
Definition
the description of how tightly clustered the distribution is around it center. measures of spread include the IQR and the standard deviation
Term
variance
Definition
the standard deviation squared
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