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The Vocabulary of Science

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Title: The Vocabulary of Science


1
The Vocabulary of Science
1. Concepts 2. Operationalization 3. Direction
of the relationship 4. Level of measurement
2
Concepts
  • Concept is an abstraction/representation of an
    object or a behavioral phenomenon
  • Each discipline develops its unique set of
    concepts
  • Political science power, social status,
    relative deprivation
  • Psychology depression, perception,
    learning
  • Sociology social status, role

3
Why do we need concepts?
  • Concepts provide a common language, which enables
    scientists to communicate with one another within
    an area
  • Power can mean different thing to different
    people
  • Science cannot progress with ambiguous and
    imprecise language
  • Vocabulary of science

4
Vocabulary of science
  • Conceptual Definitions (definitions that describe
    concepts by using other concepts)
  • Power has been conceptually defined as the
    ability of an actor (group/the state) to get
    another actor to do something that the latter
    would not otherwise do
  • Concepts ability, actor, group, state can be
    defined by other concepts, and so on.

5
Vocabulary of science
  • At a certain point in this process, scientists
    encounter concepts that cannot be defined by
    other concepts
  • These are called primitive terms
  • For example, a group is two or more individuals
  • Use of primitive terms is less efficient than use
    of more complex concepts it is easier to say
    the word group than constantly repeat the
    primitive terms that compose the definition of
    group.

6
Concepts Variables
  • A variable is any entity that can take on
    different values.
  • Anything that can vary can be considered a
    variable
  • For instance, age can be considered a variable
    because age can take different values for
    different people or for the same person at
    different times
  • Similarly, country can be considered a variable
    because a person's country can be assigned a value

7
Variables
  • Variables aren't always 'quantitative' or
    numerical
  • The variable 'gender' consists of two text
    values 'male' and 'female'.
  • We can, if it is useful, assign quantitative
    values instead of (or in place of) the text
    values, but we don't have to assign numbers in
    order for something to be a variable

8
Attribute
  • An attribute is a specific value on a variable
  • The variable sex or gender has two attributes
  • 1 male
  • 2 female

9
Attribute
  • The variable agreement might be defined as having
    five attributes
  • 1 strongly disagree
  • 2 disagree
  • 3 neutral
  • 4 agree
  • 5 strongly agree

10
Variable should be exhaustive
  • Each variable should be exhaustive, it should
    include all possible answerable
    responses/attributes
  • Variable Religion"
  • 1. "Protestant",
  • 2. "Jewish
  • 3. "Muslim"
  • The list does not exhaust all possibilities.
  • The way to deal with this is to explicitly list
    the most common attributes and then use a general
    category like "Other" to account for all
    remaining ones.

11
Attributes should be mutually exclusive
  • No respondent should be able to have two
    attributes simultaneously
  • Variable "Employment Status
  • 1) "employed
  • 2)"unemployed"
  • But these attributes are not necessarily mutually
    exclusive -- a person who is looking for a second
    job while employed would be able to check both
    attributes!
  • we can ask the respondent to "check all that that
    apply" and then list a series of categories

12
Mutually Exclusive Attributes
  • With whom do you currently live? (Choose all that
    apply)
  • Alone
  • Roommate(s)
  • Housemate(s
  • Spouse
  • Partner
  • Parent(s)
  • Other relative(s)
  • Other________________

13
Types of Variables
  • Independent Variable (Causal variable, variable
    you change
  • Dependent variable (Effect, variables you are
    trying to predict)

Independent Variable
Dependent Variable
14
Types of variables
Independent Variable
Dependent Variable
Male
lt 5,000
gt 5,000
Attributes
Attributes
15
Hypotheses
  • After we indentify the variables of interest, we
    posit a relationship between themHYPOTHESIS
  • Hypotheses can be either true or false
  • We create them in order to test whether the
    posited relationship between the variables are
    true or false

16
Example
  • H1 Gender affects occupation
  • H2 Differences in age are related to difference
    in income

17
Relationship between Variables
  • Positive
  • An increase/decrease in the independent variable
    yields an increase/decrease in the dependent
    variable
  • Independent variable/ dependent variable
  • Independent variable/ dependent
    variable

18
Example of positive relationship
  • H1 People with higher education are more likely
    to earn more money
  • Dependent variable
  • Independent variable

19
Relationship between Variables
  • Negative
  • An increase/decrease in the independent variable
    yields a decrease/increase in the dependent
    variable
  • Independent variable/ dependent variable
  • Independent variable/ dependent variable

20
Example of negative relationship
  • H1 Increased exercise causes decreased weight
  • H2 The higher your social class the less likely
    you are arrested for committing a crime
  • Dependent variable
  • Independent variable

21
Undetermined
  • H1 Males are more likely to earn more money than
    females are
  • Independent variable / dependent variable

Male
Low Income
Female
High income
22
Practice
  • Let say you want to test the relationship between
    exercise and weight
  • Formulate the hypothesis which posits a positive
    relationship between these two variables

23
Operational Definition
  • After we select variables and formulate the
    hypothesis, we must create operational definition
    for each of our variables
  • Operational definition transforming a variable
    into something we can observe
  • Listing attributes

24
Operationalizing
  • Gender
  • Female
  • Male

25
Operationalizing
  • Occupation
  • Professional
  • Manager or owner of business
  • Skilled laborer
  • Unskilled laborer
  • Not employed
  • Other

26
Operationalizing
  • Income
  • 5,000 or less
  • 5, 001-15,000
  • 15,001-25,000
  • 25,001-35,000
  • 35,001-50,000
  • 50,001 or more

27
Practice in Operationalizing
  • Marital status
  • Never married
  • Married
  • Divorced
  • Separated
  • Widowed
  • Other

28
Operationalization
  • Love

29
Sternberg (1988) The Psychology of Love
  • Emotional Intimacy dimension focuses on
    friendship, trust and feelings of emotional
    closeness that result from being able to share
    one's innermost thoughts and feelings with a
    partner
  • The passion dimension focuses on those intense
    feelings of arousal that arise from physical
    attraction and sexual attraction
  • The commitment dimension of love is often viewed
    as the decision to stay with one's partner for
    life. Commitments may range from simple verbal
    agreements (agreements not to become emotionally
    and/or sexually involved with other people) to
    publically formalized legal contracts (marriage)

30
Love
  • Desiring to promote the welfare of the loved one
  • Experiencing happiness with the loved one
  • Having high regard for the loved on
  • Being able to count on the loved one in times of
    need
  • Mutual understanding with the loved one
  • Sharing one's self and one's possessions with the
    loved one
  • Receiving emotional support from the loved one
  • Giving emotional support to the loved one
  • Having intimate communication with the loved one

Response categories Always Often
Occasionally Rarely Never
31
Why is Level of Measurement Important?
  • First, knowing the level of measurement helps you
    decide how to interpret the data from that
    variable
  • Second, knowing the level of measurement helps
    you decide what statistical analysis is
    appropriate on the values that were assigned
  • If a measure is nominal, then you know that you
    would never average the data values or do a
    t-test on the data.

32
Four levels of measurement
  • Nominal
  • Ordinal
  • Interval
  • Ratio

33
Nominal Measurement
  • At the nominal level of measurement, numbers or
    other symbols are assigned to a set of categories
    for the purpose of naming, labeling, or
    classifying the observations
  • Gender is an example of a nominal level variable.
  • Using the numbers 1 and 2, for instance, we can
    classify our observations into the categories
    "females" and "males,"
  • When numbers are used to represent the different
    categories, we do not imply anything about the
    magnitude or quantitative difference between the
    categories.

34
Nominal Variables
35
Ordinal variables
  • In ordinal measurement the attributes can be
    rank-ordered.
  • For example, on a survey you might code
    Educational Attainment as
  • 0 less than H.S.
  • 1 H.S. degree
  • 2 college degree
  • 3 post college
  • In this measure, higher numbers mean more
    education
  • But is distance from 0 to 1 same as 2 to 3? Of
    course not. The interval between values is not
    interpretable in an ordinal measure

36
Ordinal variable
  • Overall, how satisfied or dissatisfied are you
    with the quality of education that you are
    getting at WSU?
  • 1Very satisfied
  • 2Somewhat satisfied
  • 3Neither
  • 4Somewhat dissatisfied
  • 5Very dissatisfied

37
Interval variables
  • In interval measurement the distance between
    attributes does have meaning
  • For example, when we measure temperature (in
    Fahrenheit), the distance from 30-40 is same as
    distance from 70-80

38
Interval variable
  • The interval between values is interpretable
  • We can compute an average of an interval variable
  • There is no absolute zero
  • But note that in interval measurement ratios
    don't make any sense - 80 degrees is not twice as
    hot as 40 degrees (although the attribute value
    is twice as large)

39
Ratio-level variables
  • In ratio measurement there is always an absolute
    zero that is meaningful
  • This means that you can construct a meaningful
    fraction (or ratio) with a ratio variable
  • Weight is a ratio variable
  • In applied social research most "count" variables
    are ratio, for example, the number of clients in
    past six months.
  • Why? Because you can have zero clients and
    because it is meaningful to say that "...we had
    twice as many clients in the past six months as
    we did in the previous six months."

40
Hierarchy of levels
  • There is a hierarchy implied in the level of
    measurement idea.
  • At lower levels of measurement, assumptions tend
    to be less restrictive and data analyses tend to
    be less sensitive
  • At each level up the hierarchy, the current level
    includes all of the qualities of the one below it
    and adds something new
  • In general, it is desirable to have a higher
    level of measurement (e.g., interval or ratio)
    rather than a lower one (nominal or ordinal).

41
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42
Exercise
  • Political Affiliation is measured as
  • 0 Republican
  • 1 Democrat
  • 2 Independent
  • 3 Reform Party
  • 4 Green Party
  • 5 Socialist
  • 6 Other
  • This measure is a(n) _____ scale
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