Chapter 1 Flashcards
Descriptive Statistics
methods of organizing, summarizing, and presenting data in an informative way
Inferential Statistics
a decision, estimate, prediction, or generalization about a population based on a sample
What may a population also consist of?
-individuals -objects
Population
Sample
is a portion, or part, of the population of interest
Does a population have to be large?
NO! but it can be -it can be 5 employees
Qualitative or Attribute Variable
-characteristic being studied is nonnumeric
Quantitative Variable
information is reported numerically
How can quantitative be classified?
discrete or continuous
Classify: Quantitative or Qualitative? Marital Status/Hair Color
Qualitative
Classify: Quantitative or Qualitative? Income/Number of Vehicles
Quantitative
Discrete Variables
can assume certain values and there are usually “gaps” between values
Continuous Variable
can assume any value within a specified range
Classify: Continuous or Discrete Children in a Family/ Strokes on a Golf Course/ TV Sets Owned
Discrete
Classify: Continuous or Discrete Income Tax Paid/ Weight of a Student/Yearly rainfall in a City
Continuous
Nominal Level
-data that is classified into categories and cannot be arranged in any particular order
Properties of Nominal Level
-observations of a qualitative variable can only be classified and counted -there is no particular order to the labels
Ordinal Level
-data arranged in some order but the differences between data values cannot be determined or are meaningless
Properties of Ordinal Level
-data classifications are represented by sets of labels or names( high, medium, or low) that have relative values -because of the relative values, the data classified can be ranked or ordered
Interval Level
Similar to the ordinal level, with the additional property that meaningful amounts of differences between data values can be determined. There is no natural zero point.
Properties of Interval Level
-Data classifications are ordered according to the amount of the characteristic they possess -equal differences in the characteristic are represented by equal differences in the measurements
Ratio Level
the interval level with an inherent zero starting point. Differences and ratios are meaningful for this level of measurement
Properties of Ratio Level
-ordered according to the amount of the characteristic they posses -equal differences in the characteristic are represented by equal differences in the numbers assigned to the classifications -the zero point is the absence of the characteristic and the ratio between two numbers is meaningful -practically all quantitative data is recorded on the ratio level of measurement. Ratio level is the “highest” level of measurement.
What is the highest level of measurement?
Ratio
Do the levels of measurement in order?
-nominal -ordinal -interval -ratio
Statistics
the science of collecting,organizing,presenting, analyzing, and interpreting data to assist in making more effective decisions
Qualitative uses what levels and what is it the result of ?
-nominal and ordinal -and is the result of counts
Quantitative uses what levels and is the result of what?
-can use either interval or ratio -has natural order
