Unit 1 Stats

categorical

places individuals into groups

numerical discrete

random variables arise from counting something

numerical continous

arises from measuring, height, time

income

numerical discrete

frequency table

displays counts

relative frequency table

displays percentages

pie chart

%, must add to 1100

conditional prob

describes the values of the variable among individuals who have a specific value of another variable (within table)

marginal prob

distribution of values of all individuals described by a table (outside table)

how to organize a 4 step process

state, plan, do , conclude

simpson’s paradox

association btw 2 variables that holds for each individual value of a third variable can be changed or reversed when the data for all values are combined

describing quantitative data

socs

socs

shape, outlier, center, spread

skewed right

tail is on right

center

median, mean

spread

range, standard deviation

segmented bar graph

stack up bars to make 100%

mosaic plot

segment bar graph where width of bars is proportional to group size

association

if knowing the value of one variable helps us to predict the value of the other variable