**Questions for
the mid-term exam (2007)**

From Lesson 1: SPSS offers a wealth of possibilities for further analysis, but let’s limit it here to a simple example. Let us ask for the correlation in citing patterns among our five initial protagonists of the search. Analyze > Correlation > Bivariate > bring the five names to the right side and click OK. The Pearson correlation matrix is generated. What do you see? Can you interpret this result? Write a single paragraph and hand this in with the mid-term exam. (Similarly, but a bit more complex you can generate the cosine matrix using SPSS.)

From Lesson 3: The data in the file which you downloaded from the webpage contains additional information about the relative share of the citations of the journals. After each label an x-factor and an y-factor are specified. You can turn this additional information on by using Options > Size > of Vertices defined in input file. You may have to adjust the size. The nodes are now depicted proportional to the y-factors and the x-factors in the input file. The y-factor provides the percentage of the citations in this local environment, and the x-factor this same percentage after correction for “within-journal self-citations,” that is, the value on the main diagonal of the citation matrix. What do you see if you turn this on? Export this picture and make it part of the submission for the third mid-term by importing the picture into Word.

From Lesson 4: Let us return to Pajek and run Net > Vector > (1) Closeness and (2) Betweenness. See the pictures and generate similar files with the extension .rep for Closeness and Betweenness. Bring the three files into one Excel sheet and make the three measures visible using the column option of the charts. The handing in of this picture is part of the mid-term exam.

From Lesson 4: Let us go to the citing dimension by transposing the matrix. Data > Transpose. Use the variable “caselab” as the naming variable and use all the other variables for the transposition. Run the factor analysis again. How many dimensions would you choose in this case? Click on the component plot of factors 1, 2 and 3 and try to embellish it. Paste the resulting picture into your mid-term exam.

Please, hand mid-terms in hardcopy Wednesday May 2, 12 pm., Oost-Indisch Huis, my mailbox. Loet Leydesdorff