Unit 3 Flashcards
set of data in its original form
raw data
arrangement of observations according to their magnitude, either in increasing or decreasing order.
array
contains information on each member of a sample or population individually
ungrouped data
for quantitative data lists all the classes and the number of values that belong to each class
frequency distribution
Data presented in the form of a frequency distribution are called ____
grouped data
the number of observations falling in the class
class frequency
the numbers defining the class
class interval
the end numbers of the class
class limits
the true class limits
class boundaries
usually defined as halfway between the lower-class limit of the class and the upper-class limit of the preceding class
lower class boundary (LCB)
usually defined as halfway between the upper-class limit of the class and the lower-class limit of the next class
upper class boundary (UCB)
denoted by C, is the difference between the upper and lower class boundaries of a given class. It is also called the class width.
class size
midpoint of a class interval
class mark
a class that has no lower class limit or upper class limit (e.g., 92 and above)
open-end class
can be used as a first approximation of the number of classes
Sturge’s formula
what is the value or equation of the Sturge’s formula
K = 1 + 3.322logn
How to solve for the range?
max - min
how to compute for the class size?
C = R / K
(p.s. it should be rounded up to the last digit)
how to get the LCL (lower class limits)?
List the lower class limit of the first interval. Then list the successive lower class limits by adding the class width to the previous lower class limit
how to obtain the UCL (upper class limit)?
UCL = LCL + (C – unit of measure)
after getting the first UCL, list the successive upper class limits by adding the class width to the previous upper class limit
what is the formula for getting the LCB and the UCB? (upper and lower class boundaries)
LCB = LCL – 0.5(unit of measure)
UCB = UCL + 0.5(unit of measure)
how to obtain Relative Frequency (RF) Distribution & Relative Frequency Percentage (RFP)
RF = class frequency ÷ no. of observations
RFP = RF ∙ 100%
shows the accumulated frequencies of successive classes, beginning at either end of the distribution
Cumulative Frequency Distribution (CFD)
shows the no. of observations greater than the LCB.
greater than CFD
> CFD
shows the no. of observations less than the UCB
less than CFD
<CFD
How to obtain class mark?
(LCL + UCL) / 2
