SOC 206 W 2009
First assignment:
Part One
Answer the following questions in writing and
add any other idea or observation you feel pertinent.
Szelenyi, Socialist Entrepreneurs I. Szelenyi
presents three alternative explanations or theories why small-scale private
farming survived under socialism in
1. His three alternative theories shift this
historical question into a sociological one: who are the people who participate
in household farming? The actual unit of analysis is not an historical
phenomenon anymore but practices of individuals. How does Szelenyi
justify this shift ? What alternative strategies could
he have followed ?
2. For each theory Szelenyi
gives a set of empirically testable hypotheses. These hypotheses are more
specific than the theories as they identify precisely the relevant
variables/factors, and the direction of the relationship between the
explanatory variables and what is to be explained (i.e. the extent and form of
household farming).
a. First, rewrite these verbal presentations
in mathematical form saying that the variable to be explained is an unspecified
function of the explanatory variables by using one letter for each variable. Table
2.1. on p.58. will help.
E.g.
Y= f(A,B,C,D) where
Y= the value of agricultural
household production,
A= ..... etc.
A variable can have two values: 0 = No, 1 =
Yes. These are binary or so called 'dummy' variables. So the variable B could
be: whether the producer commutes to his workplace in the city (0 = does not
commute, 1 = does commute).
Get one equation for each theory. Keep
notation consistent! What do you see? What is the relationship among these
equations?
b. Given the three theories as stated by Szelenyi, what other explanatory factors/variables should Szelenyi have included?
3. Present the three equations as a flow
chart (causal diagram).. Szelenyi
makes use of various metaphors quite often throughout the book. Give at least
one example.
Part Two
In his book Szelenyi presents a series of regression models. In Figure 5.1 he presents them as four nested models [Model A, B, C, D]. In Chapter 5 he presents all four models.
The models he uses are a strange version of regression. Concentrate on the second set of columns labeled 'Regression.'
Compare the regressions in Tables 5.3-6.
Interpret the significant coefficients in Table 5.6. Is there any coefficient that became non-significant as new independent variables were included? If yes, how does Szelenyi explain that and how would you?
Part Three
Take three variables: one dependent with at
least 5 categories and at least ordinal level of measurement (Y) and two other
variables (X,Z) with at least ordinal level of
measurement (dichotomies are OK). Formulate a hypothesis that link Y and X and
present a short explanation (theory) why they are linked.
1. Present a second hypothesis that explains
the relationship between Y and X in terms of Z.
a. Write out these two equations in
mathematical form.
b. Present them in the form of causal
diagrams.
2. Create a scatter plot of Y and X.
a. Run the regression of Y on X. Interpret
the results. (Slope, intercept, R-square, F and t statistics.)
b. Create a 3-D scatter plot of Y and X and
Z.
c. Run the regression of Y on X and Z. Save
the residuals (RES) and the predicted value (PRED). Did the effect of X on Y
change? Does Z have an effect? Interpret the results. Looking at Beta, which
has a stronger impact X or Z?
d. Run a correlation between Y, X, Z and the
RES and PRED. What do you see?
Present your best multiple regression model using as many independent variables as you need.
Interpret the results.
Hand in your output with your assignment.