1. The Vocabulary of Science
Dr. John Bradford

2. Three types of Studies
• There are 3 different types of studies that
correspond to 3 different sorts of dependent
variables (Y), or objects of investigation…
1. Case study (what causes an event or condition)
– Often we aren’t interested in Y itself as a fact or event,
but changes in Y across time (longitudinal study) or
differences in Y across space (cross-sectional study).
2. Cross-sectional study (comparison across space)
3. Longitudinal study (comparison across time)

3. Levels of Knowledge
1. Descriptive/factual/observational- report data.
– I know it because I saw it or heard it, and if someone else were
there, they would have heard or seen the same thing.
2. Inferences or Assumptions-
– Statements made about something we don’t know, on the basis
of what we do know. Most common form of knowledge.
3. Evaluations/Judgments:
– An expression of approval or disapproval to assumptions we
made, whether or not it is based on something we have seen or
heard.
– Example: “John is a total jerk!”
– They do not convey why we feel the way feel. Abstract
judgment words are more about selves and the hidden feelings
we want to express.

4. What’s a Good Explanation?
• “A scientific theory should be as
simple as possible, but no
simpler.” - Einstein
• This idea that (all other things
being equal) the simpler of two
theories is the better theory, is
called the principle of parsimony,
or ‘Occam’s razor’
• Question: Can you think of
reasons why a simpler explanation
might be a better explanation?

5. Three Simple Steps to Social Science
(easier said than done)
STEP 1: Select some concepts of interest
(variables)
STEP 2: Posit (suggest) some relationship
between these concepts (Hypothesis)
STEP 3: Test these suggestions empirically to
see if they are right.

6. Concepts and Constructs
• Concept: a label that is applied to things with
similar characteristics or attributes; a
generalization, or category.
• Constructs: an abstract concept; words used
to describe things that exist analytically (in our
minds) but are not directly observable or
perceivable.
– Examples: Racism, love, economic depression,
loyalty, etc.

7. What are Variables?
• Variable: something of interest to a social
researcher.
• Variables have two characteristics:
1. It is thought to influence or be influenced by
another thing.
2. A variable is some attribute of a category of things
that has more than one possible ‘value’
– A ‘variable’ is not a constant! Not all observed cases
are identical with respect to this value.
– Variables imply differences and hence comparability.

8. Variable Definitions
• Here are some more ways of defining
‘variable’:
– A variable is a characteristic or value that can
change or be changed.
– A category or attribute with more than one
possible type or value.
– A category of things with observed differences or
changes.
– a quantity that may assume any one of a set of
values (Merrian-Webster)

9. Variables: Cause and Effect
• Below are some examples of how two variables may relate
causally. We usually designate with an ‘X’ the variable we
think is ‘causing’ (‘influencing’, ‘effecting’ etc.) the other
variable, which we designate as Y.
• X Y
• Examples:
– Gender (X) is thought to influence occupation (Y)
– Religious affiliation (Y) is thought to be influenced by income.
– Educational attainment (X) is thought to influence income (Y).
– Age (X) is thought to influence attitudes towards using
computers (Y)
– Income (Y) is thought to be influenced by race (X)

10. Variables:
Independent (X) vs Dependent (Y)
• Independent variable (X) = the cause.
Variable that influences.
• Dependent variable (Y) = the effect. Variable
that is influenced by the cause; it is dependent
on the cause.
• INCA: the INdependent variable is the CAuse.

11. Directionality
• Variables that vary in the same
direction have a positive
relationship.
• Variables that vary in the opposite
direction have a negative
relationship.
– Example: a decrease in employment
is associated with a decrease in
income:
– Even though both variables go
down, they vary in the same
direction. This is a positive
relationship! (-1 * -1 = + 1)

12. Operational Definitions
• Creating an operational definition involves
transforming the variables into things that can
be observed and measured.
• Operational just means ‘working’: you are
creating a ‘working’ definition, i.e. one that
you can use!

13. Mean, Median, Mode
• Mean is the average: add up the values and
divide the result by the number of cases.
• Median is the number in the middle so that
half of the numbers in the set are above this
number and half are below it.
• Mode is the number that occurs most
frequently.

14. Quantitative and Qualitative Research
1. Quantitative Research
– Gathers data that are easily expressed in numbers
– Emile Durkheim felt that the goal of sociology was to
discover the laws that govern social behavior
2. Qualitative Research
– Focuses not only on objective nature of behavior but
also on its meaning
– Max Weber thought that sociology had to be an
interpretive science- it must take into account the
social meanings/reasons attached to behaviors.