Quiz 1 Flashcards
Survet definition
uncontrolled collection of available. You can only use what we have
experiment defintion
controlled generation and collection of data
population definition
collection of all subjects or objects of interest
sample definition
a subset of the population, selected by some members of the given population,
sampling definition
a way of generating a sample by selecting some members of the given population
What does the sample represent?
the population or close to it
definition of statistic
a numerical measure obtained from a sample used to categorize the sample.
definition of parameter
a numerical measure that characterizes the entire population
In most cases, can we calculate the parameter
no
definition of simple random sample
random sample in which each group member has the
same probability of being selected.
How is simple random sample usually obtained
by using random numbers
definition of random numbers (n)
a collection of numbers that are each likely to occurr with probability 1/n for each number
What are the 2 properities of random numbers
Each digit 0, 1, 2, . . . , 9 is equally likely to occur.
(2) The value of any particular digit is independent of the value of any other digit
selected.
definition of bias
anything that produces systematic errors in data
definition of sampling bais
systematc error to a nonrandom nature of the sample