MATH 202 Applied Stats Section 1-1 & 1-2 Notes

Data

collection of observations; measurements, survey responses

Statstics

the science of planning studies and experiments, collecting

data, and then organizing, summarizing, presenting, analyzing,

interpreting, and drawing conclusions based on the data.

Population

collection of all elements of interest in a particular study

Census

collection of data from every member of the population

Sample

subset of the population; part of the population

must be collected through random selection

Sample Data

Parameter

numerical measure describing a characteristic of the

population

Statistic

numerical measure describing a characteristic of a sample

Quantative Data

numerical data where arithmetic calculations are

used (averages)

Qualative Data

categorical data; attribute data

- data where characteristics fall into categories

categories can be assigned numbers but the numbers have no

meaning except to represent the categories

- when the categories can be ordered, it is Ranked Data

Discrete Data

number of possible values is countable

Continous Data

infinite number of possible values; uncountable; values

within intervals (measurements)

Nominal

ata consists of names or categories; data cannot be

arranged in an order

Ordinal

order of the categories is meaningful but the differences

between the data values are meaningless

Interval

ifferences between data values are meaningful but ratio

between them is meaningless; does not have a natural zero starting

point

Ratio

atio of the data values is meaningful; has a meaningful zero

value as a starting point

Simple Random Sample

of n objects is selected in such a way that every

possible sample of the same size n has the same chance of being chosen

Random Sample

members of a population are selected in such a way

that each member has an equal chance of being selected

Sampling Error

difference between a sample result and the true

population result