Unit 1 Flashcards
area principle
when amounts are compared, they must be proportional
relative
percentage
association or dependence
if knowing one variable, helps to predict the value of another
marginal distributions
the totals of every category
conditional distributions
restraints on calculations
Simpsons paradox
when averages are taken across different groups they appear to contradict the overall averages
the W’s
who, what, where, when, why, how
mean
average
median
middle number
mode
what occurs the most
outlier
a piece of data that is unusually low or high
simulation
a random re-enactment of data collection under one or more assumptions
standard deviation
average distance of the data points from the mean
variance
sum of squared deviations from the mean divided by (n-1)
percentile
data at or below a data piece
quantitative (discrete)
countable numbers; no decimals
quantitative (continous)
an infinite amount of possible answers between each set
quantitative data condition
the data values of a quantitative variable whose units are known
categorical data condition
the data are counts or percentages of individuals in non-overlapping categories
contingency tables
compare all levels of two categorical variables for the purpose of seeing if there is an association
dot plots
a way of tracking data when you have very little
histograms
divides number line into equal intervals and displays the number of data values in each data
frequency table
lists categories and how many belong to each one
segmented bar graph
used to compare conditional distributions
interquartile range
tells us how spread out the middle 50% is
boxplot
divides the data into equal parts and displays the portion of the number line each part covers
mosaic plot
accounts for the number of pieces of data in each group; frequency shows up at area
ogive graph
cum. frequency graph
