exam review Flashcards
nominal variable
Defined catagories
Ordinal variables
ordered catagories
discrete variablr
counted items
continuous varible
measured characteristic
population
contains all of the items or indiviudals of interest that you seek to study
sample
contains only a portion of a population interest
population parameter
summarizes the value of a specific variable for a population
sample statistic
summarizes the value of a specific variable for sample date
startified sample
Drawn from random groups
Systematic sample
drawn from a big group
coverage error
some groups are excluded
Non response error
some people wont respond and their answer could differ
Sample error
variation from sample to sample will always exist
Measurement error
Due to weakeness in question design
WHat number of classes does the book reccomend
5-15
Pareto
first catagories are most important
Left skew
mean < median
symmetric
mean = median
right skew
median<mean
in ER how much date is within 1 SD of the mean
68%
in ER how much date is within 2 SD of the mean
95%
in ER how much date is within 3 SD of the mean
99.7
Covariance is bigger thaN 0
Same direction
Covariance is smaller than 0
opposite direction
