Term
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Definition
is a collection of methods for planning experiments, obtaining data, and then organizing, summarizing, presenting, analyzing, interpreting and drawing conclutions based on the date.
Example: A sample of students is selected from BC
and their average (mean)
age in years is 23.7. |
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Term
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Definition
is the complete collection of all elements (scores, people, measurements, and so on) to be
studied. The collection is complete in the sense that it includes all
subjects to be studied.
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Term
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Definition
is a subcollection of elements selected from a population.
Example
: In a study of household incomes in a small to
wn of 1000 households, one
might conceivably obtain
the income of every household. However, it is probabl
y very expensive and time consuming to do this.
Therefore, a better approach would be to obtain the
data from a portion of the households (let’s say 125
households). In this scenario, the 1000 households ar
e referred to as the populat
ion and the 125 households
are referred to as a sample. |
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Term
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Definition
is a numerical measurement describing some characteristic of a
population.
Example: In a study of all current major league baseball players,
it was found that 78% batted
exclusively right-handed. |
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Term
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Definition
is a numerical measurement describing some characteristic of a sample.
Example
: In the household incomes example from above,the average (mean) income of all 1000 households
is a parameter, whereas the average (mean) income of the 125 households is a statistic. |
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Term
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Definition
result when you can make a list of all possible values. The use of “...” is permitted when there is an infinite number of possible values.
Example: A research poll of 1015 people shows that 752 of them have internet access at work. |
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Term
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Definition
result when there is an infinite number of possible values that cannot be made into a list.
This type of data is often associated with some sort of physical measurement.
Example
: The finishing times of a marathon
In a study of all current major league baseball players, it was found that 78% batted exclusively right-handed. |
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Term
The
nominal level of measurement |
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Definition
is characterized by data that consist of names, labels or categories
only.
The data cannot be arranged in an ordering scheme (such as low to high).
Example
: The type of blood one has (A, B, AB, or O)
Responses to an exit poll were made by 45 Democrats and 80 Republicans and 90 Independents. |
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Term
the
ordinal level of measurement |
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Definition
is characterized by data that may be arranged in some order, but
differences between data values either
cannot be determined or are meaningless.
Example
: The ranking of a college football team (1, 2, 3, etc.)
In a sample of 36 stereo speakers, 12 were rated "good", 16 were rated "better" and 8 were rated "best". |
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Term
The
interval level of measurement |
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Definition
is the same as ordinal level, except that differences between data values
are meaningful
. In addition, there is
no inherent (natural)
zero starting point.
Example
: The record low temperature for a certain city on this date.
The years in which the US was struck by a hurricane. |
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Term
The
ratio level of measurement |
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Definition
is the same as interval level, except that there is an inherent (natural) zero starting point (where zero indicates that none of the quantity is present). For values at this level, differences and ratios are meaningful.
Example
: The price of a textbook. Note: A
$4 item costs twice as much as a
$2 item ($4/$2 = 2). Thus, the
ratio of $4 to $2 is meaningful. However, a 4 star restaurant is not necessarily twice as good as a 2 star
restaurant even though 4/2
= 2. In this case, the ratio of 4
stars to 2 stars would be meaningless.
The lengths (in minutes) of movies that are currently playing at a movie theater complex. |
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