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Define Statistics

math that transforms numbers into useful information for decision makers

Define descriptive statistics

focuses on collecting, summarizing, presenting, and analyzing a set of data( tables, charts)

define inferential statistics

data that have been collected from a small group to draw conclusions about a larger group. To make decisions about which investment might lead to a higher return and what marketing strategy might lead to increased sales

operational definitions

universally accepted meanings that are clear to all associated with an analysis

Population

consists of all the items or individuals about which you want to draw a conclusion

Sample

a portion of population for analysis

Parameter

numerical measure that describes a characteristic of a population

Statistic

numerical measure that describes a characteristic of a sample

data collection

collecting the values for those variables

Primary sources

When the data collector is the one using the date for analysis

Secondary sources

Person forming the statistical analysis is not the data collector

Categorical variables(qualitative)

Values that can only be placed into categories. Ex. Yes or No

Numerical variables(quantitative)

Values that represent quantities. Ex. How many or How much?

Discrete variables

numerical values that arise from a counting process. Ex. number magazines subscribed to

Continuous variables

numerical responses that arise from a measuring process. Ex. Time to wait

Nominal scale

classifies data into distinct categories in which no ranking is implied.Ex. buy a product in 12 months

Ordinal scale

classifies data into distinct categories in which ranking is implied. Ex. Rate satisfaction

Interval scale

ordered scale in which the difference between measurements is a meaningful quantity but does not involve a true zero point

Ratio scale

ordered scale in which the difference between the measurements involves a true zero point such as height or weight.

frequency distribution

a summary table in which the data re arranged into numerical ordered classes

width class interval

divide the range(highest value- lowest value) by the number of classes desired.

Relative Frequency

Frequency in each class/total # of values