All example exam questions
Example exam question 1.1
Sometimes, similarities in attributes between individuals are translated
into foci (Feld, page 1019). Give an example of a focus where this is the
case (and explain).
Focus: A focus is any social, psychological, or physical entity around which
joint activities of individuals are organized.
Individuals who share a focus are more likely to share joint activities with
each other than two individuals who do not have that focus in common
(Feld, 1981, p. 1025). Example: Paralympics sports team
Example exam question 1.2
What are local bridges in a network? How compatible are they with Focus
Theory and Balance Theory?
Local bridge: an edge joining two nodes who have no friends in common
Span of a local bridge: The distance between the two endpoints (i.e., the
two nodes that are joined) of a local bridge if the edge between these
endpoints is deleted
Balance theory is not good at explaining the existence of local bridges.
Balance theory argues that individuals strive for cognitive balance, which
results in triadic closure: A friend of a friend is my friend. According to
balance theory, local bridges are unstable.
Focus theory can explain the existence of local bridges, but ONLY when
you specify extra conditions. Focus theory argues that time pressures may
stimulate actors to create transitivity, new foci, or withdraw from a focus.
Focus theory would only expect local bridges to be stable if the focus is
undemanding and incompatible with other foci.
,Example exam question 1.3
Country 1 (Mixed) N=200, group A 50% (N=100) and group B 50%
(N=100)
Country 2 (Homogenous) N=200, group A 90% (N=180) and group B
10% (N=20)
Calculate the number and percentage of interethnic marriages for Group A
and B in both countries, if marriages are random (so no preferences for
own ethnic group exist). Assume gender is not a factor in marriages.
Country 1: Group A Endogamous : AA = 100 * .5 = 50 (or 25 marriages)
Exogamous : AB = 100 * .5 = 50 (or 25 marriages) so 50% of group A
endogamous and 50 % exogamous Group B Exogamous : BA = 100 * .5 =
50 (or 25 marriages) Endogamous : BB = 100 * .5 = 50 (or 25 marriages)
so 50% of group A endogamous and 50 % exogamous
Country 2: Group A Endogamous : AA = 180 * .9 = 162 (or 81 marriages)
Exogamous : AB = 180 * .1 = 18 (9 marriages) so 90% of group A
endogamous and 10 % exogamous Group B Exogamous: BA = 20 * 0.9 =
18 (or 9 marriages) Endogamous: BB = 20 * 0.1 = 2 (or 1 marriage) so
90% of group B exogamous and 10% endogamous
General formula XY = nX * py , where nX = number of persons in group X
and py = chance of marrying person of group Y If marriage is random,
chance of marrying person of group Y = proportion of group Y in
population
Random/opportunity: Country 1 (50/50): 50 interethnic marriages Country
2 (90/10): 18 interethnic marriages
Example exam question 2.1
You want to study how networks help people find jobs. Come up with two
(briefly explained) research designs to investigate this: once using
complete network data, once using ego-network (personal) data.
Discuss the potential difference in findings and conclusions these two
strategies would yield.
, Complete network data focuses on broader patterns. You would study the
entire company and look at the social connections people have. How does
the position of someone influence the job opportunities.
Ego-network data focuses on the more personal things. You would study
the personal contacts a person has and how this influences the job
opportunities.
Difference is that complete network data focuses on the bigger picture,
while the ego-network focuses on more personal level
Example exam question 2.2
In the small-world experiment, documents that arrived at the target
person did so in a chain of on average 6 hops. However, most documents
never arrived because someone failed to forward it. Imagine that all
document chains had instead been forced to completion, would Milgram
then have found them on average to be shorter or longer? Motivate your
answer.
Mentioned in the article: With each hop there is a chance that the present
holder of the document fails to forward it. In the experiment, shorter
chains were therefore more likely to be completed. Hence, if all chains had
been forced to completion, Milgram would have found them to be longer
on average.
Intuitive reasoning behind why people do not complete (which may also
affect chain length): People do not forward because they do not know a
good intermediate
Example exam question 2.3
Show that a regular ring lattice network with 1000 nodes and 10 edges per
node is not a small world. Explain your answer.
Small worlds meet the requirement that Lactual is almost as short as
Lrandom
Network that we study: regular ring lattice with n = 1000, k = 10
Lactual = Lregular = n / 2k = 1000 / (2 x 10) = 50
Lrandom = ln(n) / ln(k) = ln(1000) / ln(10) = 3
Conclusion: 50 is a much longer average path length than 3. Hence, this is
not a small world.
Example exam question 1.1
Sometimes, similarities in attributes between individuals are translated
into foci (Feld, page 1019). Give an example of a focus where this is the
case (and explain).
Focus: A focus is any social, psychological, or physical entity around which
joint activities of individuals are organized.
Individuals who share a focus are more likely to share joint activities with
each other than two individuals who do not have that focus in common
(Feld, 1981, p. 1025). Example: Paralympics sports team
Example exam question 1.2
What are local bridges in a network? How compatible are they with Focus
Theory and Balance Theory?
Local bridge: an edge joining two nodes who have no friends in common
Span of a local bridge: The distance between the two endpoints (i.e., the
two nodes that are joined) of a local bridge if the edge between these
endpoints is deleted
Balance theory is not good at explaining the existence of local bridges.
Balance theory argues that individuals strive for cognitive balance, which
results in triadic closure: A friend of a friend is my friend. According to
balance theory, local bridges are unstable.
Focus theory can explain the existence of local bridges, but ONLY when
you specify extra conditions. Focus theory argues that time pressures may
stimulate actors to create transitivity, new foci, or withdraw from a focus.
Focus theory would only expect local bridges to be stable if the focus is
undemanding and incompatible with other foci.
,Example exam question 1.3
Country 1 (Mixed) N=200, group A 50% (N=100) and group B 50%
(N=100)
Country 2 (Homogenous) N=200, group A 90% (N=180) and group B
10% (N=20)
Calculate the number and percentage of interethnic marriages for Group A
and B in both countries, if marriages are random (so no preferences for
own ethnic group exist). Assume gender is not a factor in marriages.
Country 1: Group A Endogamous : AA = 100 * .5 = 50 (or 25 marriages)
Exogamous : AB = 100 * .5 = 50 (or 25 marriages) so 50% of group A
endogamous and 50 % exogamous Group B Exogamous : BA = 100 * .5 =
50 (or 25 marriages) Endogamous : BB = 100 * .5 = 50 (or 25 marriages)
so 50% of group A endogamous and 50 % exogamous
Country 2: Group A Endogamous : AA = 180 * .9 = 162 (or 81 marriages)
Exogamous : AB = 180 * .1 = 18 (9 marriages) so 90% of group A
endogamous and 10 % exogamous Group B Exogamous: BA = 20 * 0.9 =
18 (or 9 marriages) Endogamous: BB = 20 * 0.1 = 2 (or 1 marriage) so
90% of group B exogamous and 10% endogamous
General formula XY = nX * py , where nX = number of persons in group X
and py = chance of marrying person of group Y If marriage is random,
chance of marrying person of group Y = proportion of group Y in
population
Random/opportunity: Country 1 (50/50): 50 interethnic marriages Country
2 (90/10): 18 interethnic marriages
Example exam question 2.1
You want to study how networks help people find jobs. Come up with two
(briefly explained) research designs to investigate this: once using
complete network data, once using ego-network (personal) data.
Discuss the potential difference in findings and conclusions these two
strategies would yield.
, Complete network data focuses on broader patterns. You would study the
entire company and look at the social connections people have. How does
the position of someone influence the job opportunities.
Ego-network data focuses on the more personal things. You would study
the personal contacts a person has and how this influences the job
opportunities.
Difference is that complete network data focuses on the bigger picture,
while the ego-network focuses on more personal level
Example exam question 2.2
In the small-world experiment, documents that arrived at the target
person did so in a chain of on average 6 hops. However, most documents
never arrived because someone failed to forward it. Imagine that all
document chains had instead been forced to completion, would Milgram
then have found them on average to be shorter or longer? Motivate your
answer.
Mentioned in the article: With each hop there is a chance that the present
holder of the document fails to forward it. In the experiment, shorter
chains were therefore more likely to be completed. Hence, if all chains had
been forced to completion, Milgram would have found them to be longer
on average.
Intuitive reasoning behind why people do not complete (which may also
affect chain length): People do not forward because they do not know a
good intermediate
Example exam question 2.3
Show that a regular ring lattice network with 1000 nodes and 10 edges per
node is not a small world. Explain your answer.
Small worlds meet the requirement that Lactual is almost as short as
Lrandom
Network that we study: regular ring lattice with n = 1000, k = 10
Lactual = Lregular = n / 2k = 1000 / (2 x 10) = 50
Lrandom = ln(n) / ln(k) = ln(1000) / ln(10) = 3
Conclusion: 50 is a much longer average path length than 3. Hence, this is
not a small world.
