fdt Flashcards
is a tabular arrangement of data by categories and their corresponding frequencies.
Frequency distribution table
the data are incorporated in the text of the report.
Textual form
the data are presented in rows and columns.
Tabular form
utilized for an “easy to digest” information. This comes in graphs and diagrams.
graphics form
are data collected in an investigation and they are not organized systematically.
Raw data
-Raw data that are presented in the form of a frequency distribution.
Grouped data
2 METHODS OF ORGANIZING RAW DATA
Array and Stem-and-leaf display/diagram
An ordering of the observations from smallest to the largest or vice versa (low and high values can be easily perceived).
Array
gives a good overall impression of the data.
Stem and leaf
-Another way of presenting raw data is the
frequency table.
-When the data are arranged in tabular form by
the frequencies
-the arrangement itself is called
Frequency distribution
Statisticians
Freud and simon
Y =
X =
σ =
μ =
π =
e =
Y = height of the curve
X = any score in the distribution table
σ = standard deviation of the population
μ = mean of the population
π = 3.1416
e = 2.7183
z-Table also known as
the Table of Areas under the Normal Curve
e in statistics refers to the distribution of your data between the lowest and
highest values in the distribution.
range
is given by the midpoint of the upper limit of one class and the lower limit of the next
class
class boundary
The class boundary with a smaller value is referred to as the lower boundary
lower boudary
The class boundary with a higher value is referred to as the upper boundary.
upper boundary
is the average of the upper limit and the lower limit of a class in a frequency distribution.
In other words, the class mark is the mid-value of the given class interval.
class mark
The values which determine the upper and lower limits of a class
class limits
Smallest data value that can be included in the class
lower limit
Largest data value that can be included in the class
upper limit
is the number of values in a variable that is less than or equal to the value of certain variables. It equates to the total frequencies of the sum of the classes.
cumulative frequency
refers to the difference of the upper-class limit and lower-class limit.
class interval
refers to the difference between the upper and lower boundaries of a class in a frequency distribution.
class size
Numbers that are used to describe set of data are called
DESCRIPTIVE MEASURES
Another method of summarizing data is to compute numbers, such as average, that
describe a set of data.
measure of central tendecy
is a single number that represents the typical score of the data.
A measure of central allocation or central tendency
is the average value of all the data in the set.
mean
- is the value that has exactly half the data above it and half below it
median
is the value that occurs most frequently on the set.
mode
is defined as the sum of all the scores or data divided by the number of scores in the
data. In particular, the mean is denoted by x the scores
the mean for ungrouped data
In general, the weighted mean of a group of numbers or scores designated by x1, x2, .., xn Which occur W1, W2, …, Wn respectively is
weighted arithmetic mean
is average of a given set of data.
mean
Is the sum of squares of differences between all numbers and means.
variance
Square root of variance. It is a measure of the extent to which data varies from the mean
standard deviation
m = Ex * P(x)
σ² = √(x -μ)² + P(x)
σ² = √E(x -μ)² + P(x)
