Ch 1 Flashcards
Statistics
The science of collecting, analyzing, presenting and interpreting data as well as making decisions based on such analyses
Descriptive statistics
consists of methods for organizing, displaying and describing data by using tables graphs and summary measures
Inferential statistics
consists of methods that use sample results to help make decisions or predictions about a population
population
consists of all elements whose characteristics are being studied
target population
the population being studied
sample
portion of the population selected for study
census
survery that includes every member of the population
sample survery
technique of collecting information from a portion of the population
representative sample
sample that represents the characteristics of a population as closely as possible
random sample
a sample drawn in such a way that each member of a population has a chance of being selected
simple random sampling
if all samples of the same size selected from a population have the same chance of being selected
sampling with replacement
each time we select an element from the population we put it back in the population before we select the next element
sampling without replacement
occurs when the selected element is not replaced in the population
element of member of a sample population
is a specific subject or object about which the information is collected
variable
characteristic under study that assumes different values for different elements
observation or measurement
the value of a variable for an element
data set
a collection of observations on one or more variables
quantitative data
the data collected on a quantative variable
discrete variables
variable whos values are countable
continuous variable
a variable that can assume any numerical value over a certain interval or intervals
