1. GS/PPAL 6200 3.00 Research Methods and Information Systems
March 14-15, 2017
Professor Brenda Spotton Visano
Office: 130 McLaughlin
Voice Mail: (416) ext

2. Agenda Methods of Knowing Mill’s methods of knowing
Articles for review: What can small samples reveal?
Lieberson, Stanley (1991) Small N’s and big conclusions: An examination of the reasoning in comparative studies based on a small number of cases. Social Forces 70(Dec.):
Savolainen, Jukka (1994) The rationality of drawing big conclusions based on small samples: In defense of Mill’s methods. Social Forces 72(June):
Sampling and Measurement – precursor to causal inference

3. Sample Questions to which we might seek an Answer
Physical Phenomenon
How do we know ice is cold?
How could we test a hypothesis that states “all things frozen are cold”?
Social Phenomenon
How could we test a hypothesis that states “drunk driving causes automobile accidents”?

4. Causality
David Hume ( ) A Treatise of Human Nature, 1738; Hume’s Causality:
Precedence (X precedes Y in time)
Contiguity (X and Y are contiguous in time and space)
Constant Conjunction (X and Y always co-occur)
John Stuart Mill ( ), A System of Logic, 1843
Methods of (1) Agreement, (2) Difference, (3) Joint Agreement and Difference, (4) Residue, and (5) Concomitant Variations
Re: Hume’s causality: by Hume’s reasoning alone, Day causes night.
Method of Direct Agreement: If two or more instances of the phenomenon under investigation have only one circumstance in common, the circumstance in which alone all the instances agree, is the cause (or effect) of the given phenomenon.
John Stuart Mill, A System of Logic, Vol. 1  p. 454.
Method of Difference: If an instance in which the phenomenon under investigation occurs, and an instance in which it does not occur, have every circumstance save one in common, that one occurring only in the former; the circumstance in which alone the two instances differ, is the effect, or cause, or a necessary part of the cause, of the phenomenon. – John Stuart Mill, A System of Logic, Vol. 1  p. 455
Joint Method of Agreement and Difference
If two or more instances in which the phenomenon occurs have only one circumstance in common, while two or more instances in which it does not occur have nothing in common save the absence of that circumstance; the circumstance in which alone the two sets of instances differ, is the effect, or cause, or a necessary part of the cause, of the phenomenon. —John Stuart Mill, A System of Logic . Vol p. 463.
Method of residue
Subduct from any phenomenon such part as is known by previous inductions to be the effect of certain antecedents, and the residue of the phenomenon is the effect of the remaining antecedents. —John Stuart Mill, A System of Logic. Vol p. 465.
Method of concomitant variations
Whatever phenomenon varies in any manner whenever another phenomenon varies in some particular manner, is either a cause or an effect of that phenomenon, or is connected with it through some fact of causation. —John Stuart Mill, A System of Logic. Vol. 1, p. 470.

5. Method of Direct Agreement
Y occurs together with X1, X2
Y occurs together with X1, X3, X4
Therefore Y is the cause, or the effect, of X1
If Y is the effect of X1, then Y is the dependent variable, X1 is the independent variable, and by Mill’s method of agreement X1 “causes” Y

6. Method of Difference
Y occurs together with X1, X2, X3, X4
Y does not occur together with X2, X3, X4
Therefore Y is the cause, or the effect, or a part of the cause of X1.
Example of test for “drunk driving causes automobile accidents”?

7. Driver runs a red light (X4)
Method of Agreement
Accident (Y)
Drunk driving (X1)
Other car (X2)
Driver speeding (X3)
Driver runs a red light (X4)
Yes No
Method of Difference

8. Assumptions and Limitations
Assumes:
a unique cause
the causal variable is included in the set of possibilities investigated
invariance in the patterns investigated
correlation implies causation
Limitations: see Lieberson (1991) for argument opposing the use of Mill’s methods in social research and Savolainen (1994) for a defense of it