Spectral Clustering of Multiple Choice Questions
Process
Input
Answers (a-e) on 10 questions from the midterm in Computer Networks
(UCR CS164) for 53 students.
Processing
Processing was identical to the processing done in my first multiple choice clustering experiement,
with the additional step of performing spectral
clustering as a pre-processing step before running the
hierarchical clustering algorithm. (NOTE also that the spectral
clustering outputs points located in Rk, rather than the
distances between points in a (possibly non-Euclidean) space. So a
distance-finding step akin to the initial M.I. step was also performed
to allow maximal code re-use.)
About the dataset
The first 5 questions are T/F, the remaining questions are multiple
choice (5 responses).
Independent Groupings
I asked for perceived groupings of the questions from people I know
that have a strong networks background. These people were given only
the question text, as listed below, they did NOT have access to the
score information. (Conversely, this clustering is done with only
score information, not question text.) I got 5 responses, listed
here:
- T.W.
- M.B.
- Z.B.
- 4, 10
- 6, 7, 8, 9
- 3, 4, 5, 6, 7
- 2
- 1, 5, 8
- C.L.
- 1, 7, 8, 9
- 1, 7
- 8, 9
- 3, 4, 5, 6, 10
- 3, 4, 6, 10
- E.A.
- 4, 5, 10
- 3, 6, 7, 8, 9
- 1, 7, 8, 9
- 2
- 3, 4, 10
In this groupings, a number of pairings recur:
- 4, 10 @ 100%
- 3, 6 @ 100%
- 8, 9 @ 100%
Only one of these identified pairings is held up in the clustering.
Several of the more spurious clusterings are present though, such as
3, 4 @ 80% (1 level off), but many are not.
- Throughput and Latency mean basically the same thing
- In the Python socket API, the listen method of Socket objects
blocks until a new connection has been established and returns the new
connection along with the address making the connection
- The error-detection algorithm used in Ethernet depends on the
physical medium that it is used on.
- An Ethernet adaptor will only send out Ethernet frames that have
the correct Ethernet source address
- The number of TCP ports available on a host is equal to the number
of wires in the physical cable connecting the host to the
network.
- Which of the following is more of a concern in ATM than Ethernet?
- Which of the following errors can NOT be introduced by an
unreliable delivery mechanism?
- For a Stop-and-Wait protocol to transmit n frames, it requires a
sequence number of how many bit(s)?
- In a Sliding-Window protocol, the RWS governs
- Hosts on an Ethernet have to process the following fields in an
Ethernet frame header