DESCRIPTIVE Flashcards
the data in its original form, it is still unprocessed and unorganized
Raw data
consists of class and its frequency, each raw data value is placed in a particular class
Frequency distribution
organization of raw data in table form, using classes and frequencies
Freq. Distribution
quantitative or qualitative category
Class
number of data values contained in a specific class
Frequency
these are the limits, the upper and lower limit, of the class.
Class limit
Two main types of Freq. Distribution
Categorical and Grouped frequency distribution
used for data that can be placed in specific categories, such as nominal- or ordinal-level data
Categorical Frequency Distribution
since data is in categories, discrete classes can be used
Categorical Frequency Distribution
used to recheck if all data is tallied
ΣF or the Summation of Frequency
when the range of the data is large, the data must be grouped into classes that are more than one unit in width
Grouped Frequency Distribution
These numbers are used to separate the classes so that there are no gaps in the frequency distribution.
Class Boundaries
____________ are half a unit away from the class limits.
Class boundaries
The basic rule of thumb is that the _____________ should have the same decimal place value as the data, but the ____________ should have one additional place value and end in a 5.
class limits/ class boundaries
What is the class boundary for the class limit 31-37?
30.5-37.5
What is the class boundary for 7.8-8.8?
7.75-8.85
is found by subtracting the lower (or upper) class limit of one class from the lower (or upper) class limit of the next class.
Class width
The ____________ must have one more decimal place than the class limit
class boundaries
GENERAL RULES FOR CONSTRUCTING GROUPED FREQUENCY DISTRIBUTION
RULE 1. There should be between 5 and 20 classes
RULE 2. It is preferable but not absolutely necessary that the class width be an odd number
RULE 3. The classes must be mutually exclusive
RULE 4. The classes must be continuous
RULE 5. The classes must be exhaustive
RULE 6. The classes must be equal in width