Abstract
Concerns about the low completion rates in community colleges have led policy makers and administrators to examine interventions that aim to increase persistence and success by making colleges easier to navigate for students. One of the best supported and most well researched of the current reforms is guided pathways which aims to simplify student decision making. Meta majors, the grouping of all available majors into a handful of buckets, is an important components of these whole school reforms. In this paper I test an underlying assumption of this reform—that there are consistent groupings of majors that students would consider choosing—using tools from social network analysis. I draw on these consideration networks to examine how different groups of students cluster majors together; differences in how various groups of students group majors provides insight into how such interventions could increase efficiency or exacerbate inequality. These findings provide guidance for schools on what factors to consider when forming meta major groupings.
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Notes
While this rate is staggering, there are four contextual points that I think are important to keep in mind. First, graduation rates (within 150% of normative time) at community colleges have been relatively stable (around 20%) for the past decade (NCES 2015). Second, as more and more students have enrolled in college, this growth has disproportionately been carried by community colleges; students who in the past would not have enrolled in college are now enrolling in community colleges (Bryant 2001; Taylor et al. 2009). Thus, the denominator in this equation (the pool of students who could be community college graduates) is changing over time and completion rates reflect this changing population of entrants. Third, completion rates vary significantly by student characteristics. For example, students who enroll exclusively full time and students who enroll soon after finishing high school have relatively high completion rates on average (Shapiro et al. 2016). Finally, many students take a long time but eventually complete; even 6 year graduation rates aren’t generous enough. Eight year completion rates from community colleges are more than five percentage points higher than 6 year rates (Shapiro et al. 2016).
The California Community College Chancellor’s Office uses the transfer methodology used by Bahr et al. (2005): students are defined as exhibiting “behavioral intent to transfer” if, within 6 years, they have completed at least 12 units and have attempted transfer-level math or English. The CCCCO’s definition of transfer is: “percentage of first-time students with minimum six units earned who attempted any math or English in the first 3 years and achieved any of the following outcomes within 6 years of entry: (1) earned AA/AS or credit certificate, (2) transfer to 4-year institution, (3) achieved “Transfer Prepared” (student successfully completed 60 UC/CSU transferrable units with GPA ≥2.0) (CCCCO Data Mart, methodology for college level indicators).
In these classes the majority students had the goal of earning an award (certificate or degree) or transferring (whereas in explicitly career and technical education classes, most students have already decided on a program of study and thus wouldn’t be able to provide relevant context on consideration of majors). This choice of classes has implications for the generalizability of this study.
I collapsed the 89 available majors at the school into 43 categories. For example, I collapsed the four accounting specializations (bookkeeping, practice emphasis, taxation emphasis, and tax practitioner) into one major (“accounting”) and I collapsed the six automotive technician specializations (machining and engine repair, engine performance, chassis, powertrain, smog technician, advanced automotive technology) into one (“automotive technician”). The other categories that I collapsed were: administration of justice, art, business administration, child development, computer information systems, environmental studies, graphic and interactive design, health technologies, manufacturing and computer numerical control (CNC) technology, and nursing. For each group that I collapsed, I included the list of majors encompassed by this larger category the survey [e.g., “Health Tech (Ins. and coding, Med. Filing, Phlebotomy Tech.)”]. The school has seven academic divisions which I grouped into four categories: Language and Arts (comprised of creative arts, intercultural and international studies, and language arts); Business, Technology and Computer Science; Science, Math and Engineering (comprised of biological and health sciences and physical science, math and engineering) and Humanities and Social Science. Each of the survey forms included the majors from three of the four categories. Thus, across all survey forms each major was paired with each other major on at least half of the surveys. Since I was interested in examining how majors move together across the sample, and not in the consideration sets of individual students, the fact that each student did not see all available majors will not affect my results. I explain this in more detail in the Methods section.
As noted above, each pair of majors was not necessarily shown to the same number of students.
Setting the cut-off too low results in a lack of meaningful variation as we approach the point at which all nodes are connected to all other nodes. Setting the cut-off too high results in very sparse networks and loses valuable information. In Appendix 1 I present results for network-level descriptors using two other cut-off values (0.15 and 0.25). Changing the cut-off does not produce meaningful differences in the general results.
The network graphs were made using the nwcommands package in Stata (Grund 2015). The nodes are plotted using modern multidimensional scaling—proximity represents the distance between two majors, measured by shortest path between the two.
And indeed, as noted above, clustering majors by career category is a more accurate reflection of what key policy makers are encouraging schools to do.
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Acknowledgements
I’d like to thank Sean Reardon, Eric Bettinger, Tom Dee, Michal Kurlaender, Davis Jenkins, Peter Crosta, and Eliza Evans for valuable feedback and advice at various stages of this Project. Funding for this Project came from Institute of Education Sciences Grant R305B090016, The Kimball Family Graduate Fellowship at Stanford University, and the Jack Kent Cooke Foundation.
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Appendix
Appendix
Appendix 1: Network-Level Statistics Using Different Thresholds for Dichotomization
Appendix 2: Consideration Networks Graphs by Student Group
See Figs. 4, 5, 6, 7, 8, 9, and 10.
Appendix 3
Major Level Network Analyses
Information about a particular major’s location within a consideration network can also provide insight that can help administrators and policy makers structure programmatic offerings in ways that can increase success and persistence and perhaps reduce segregation. In this Appendix, I examine three statistics for each major: betweenness centrality, clustering, and homophily as well as basic descriptions of which majors are most likely to travel together. In this paper I examine the roles that majors play in the all student network. For parsimony and simplicity, I do not examine the roles of specific majors in the networks of specific groups of students. For example, I do not look at differences in the role that Biology plays in consideration networks of White and Black students. Such questions could be an interesting, and potentially policy relevant, extension to this work.
Betweenness centrality is a measure of how important a node is in terms of connecting other nodes. It is operationalized as the number of shortest paths from all nodes to all other nodes that pass through the focal node:
where m is the focal node and n,…,o is the list of all other nodes. \(l_{n \to m \to o }\) is the shortest link from node n to node o and it passes through node m, l no is the shortest link from node n to node o and it does not pass through node m. We can standardize B by dividing it by the maximum number of pairs of actors not including [(N − 1)(N − 2)]/2. This standardization bounds the betweenness centrality measure between 0 and 1 and makes it easier to compare to other statistics. A major that has a high betweenness centrality score (close to 1) will be an important “link”—it will connect disparate clusters of majors.
Understanding a major’s betweenness is important for a number of reasons. Majors that have high betweenness—that is, majors that serve as high frequency connections between other majors—could be promoted as points-of-entry majors from which students could move into disparate fields. Such “pivot” or “gateway” majors could be valuable exploratory majors for undecided students who are considering more than one discipline and could prove valuable for school and labor force planning.
The clustering of a node is an individual measure similar to the overall clustering of a network: how close a node’s neighbors are to each other. That is, how likely are my friends to be friends with each other?
where g m is major m’s set of links and l no is a link between nodes n and o, both of which are linked to node m. Thus, the clustering coefficient looks at all of the pairs of nodes that are linked to node m and examines how many of them are linked to each other (Jackson 2008). A major that has a high clustering measure is one that is in a clique—the majors that it is connected to are also connected to each other. Majors that have high values for clustering would be good candidates for a meta major.
Neighborhood context describes some aspect of all nodes n that are adjacent to node m. In this instance, I define homophily as the proportion of adjacent majors that are in the same subject group as major m. That is, how many of the majors linked to major m are in the same subject group (e.g., math and science) as major m?
Majors with high values of homophily are more often connected to similar majors. That is, students who would consider this major are more likely to consider other majors in the same general subject area or career field. Low values of homophily indicate that students who would consider this major would also consider dissimilar majors.
In the context of institutional or state policy, it is important to examine a major’s level of homophily. Meta majors tend to group majors by broad subject affiliation or by relationship to career fields. If a major has a particularly low value of homophily, grouping it with other “like” majors might not be appropriate; low levels of homophily indicate that students are grouping this major with other majors based on something other than disciplinary or career alignment.
Results
Table 5 presents descriptive information on common major pairings: if a student could consider choosing major X, what other majors is she likely to consider choosing? This table shows the majors that at least 50% of students who are considering major X would also consider choosing. For example, more than half of the students who say they would consider majoring in Communication Studies also say they would also consider majoring in: Accounting, Film and TV, Graphic Design, Leadership and Social Change, Marketing, Medical Laboratory Technician, Music, Photography, Social and Behavioral Science or Sociology.
Some of the findings presented on this table make intuitive sense and are unsurprising: students who would considering majoring in Biology are often also considering Environmental Science and Medical Lab Technician; there is evidence that students often consider majors in the same general field. However, there is also evidence that students have very different kinds of majors in their consideration sets. Many students who say they would consider majoring in Biology would also consider majoring in Art or Accounting. The groups of majors that students often consider together might not always follow the groupings of administrators; this finding provides clear evidence that groupings based on discipline might not map well onto how students group majors.
The patterns in this table also provide suggestive guidance for how schools could structure options or how they communicate about their structure. For example, if there is demand for a certain kind of training within a labor market (medical laboratory technician, for example), schools might group the introductory courses for this major with introductory courses for other popular majors that students are likely to consider with this high demand field.
Table 6 presents three statistics (betweenness centrality, clustering, and homophily) for each individual major within the consideration network for all students (a graph of this consideration network is included in Fig. 3). A couple of findings are immediately apparent. Business Administration and Sociology have very high betweenness centrality values. In the graph of this relatively sparse network, it’s easy to see how these two serve as links between groups of majors. For example, no business and technology majors are linked to any majors except for business administration. All science, math majors and language majors (Biology, Nursing, English) are connected to the business and technology majors only through Sociology. If schools were looking to help students develop tastes in certain fields (women in STEM fields, for example) or encourage students to gain skills in fields with great labor market needs (radiology technicians, for example), these gatekeeper majors could serve as important levers—first year course sequences could focus on these pivot majors and provide common basic training across a variety of programs to help students learn about different fields before making a decision.
Social and Behavioral Science and Child Development have the highest clustering coefficients in the consideration network of all students. These are majors whose “friends” are likely to be “friends” with each other. Highly clustered majors are ones that might be particularly suitable for guided pathways or exploratory majors. In this network, it’s clear that a meta major focused on social science might be productive for students; students who are considering social and behavioral science, sociology, child development, and business administration seem to be considering all of these majors with some frequency. Allowing students to consider all four in a meta major (rather than asking them to declare just one) could help students’ persistence and progress by removing one decision step and simplifying the decision process. Importantly, this potential meta major contains majors in two different disciplines, something that is relatively rare in practice.
The final statistic in this table is homophily—a measure of how alike a node’s neighbors are. Majors with high values of homophily are connected to similar majors. High values of homophily indicate that students typically only consider similar majors with this major, low values indicate that this major is connected to lots of different kinds of majors; important link majors have low values of homophily. Majors with low values of homophily might not be best suited in meta majors that are grouped by discipline. For example, in this network Sociology has a particularly low homophily score. By placing sociology in a meta major with only social and behavioral science majors, schools might force students to make decisions and close potential paths before they are ready.
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Baker, R. Understanding College Students’ Major Choices Using Social Network Analysis. Res High Educ 59, 198–225 (2018). https://doi.org/10.1007/s11162-017-9463-1
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DOI: https://doi.org/10.1007/s11162-017-9463-1