Moving beyond the deep and surface dichotomy; using Q Methodology to explore students’ approaches to studying

ABSTRACT

Student learning approaches research has been built upon the notions of deep and surface learning. Despite its status as part of the educational research canon, the dichotomy of deep/surface has been critiqued as constraining the debate surrounding student learning. Additionally, issues of content validity have been expressed concerning situational and contextual differences in its interpretation. Q Methodology was used as both a research method and an analytical technique for this study and has as its aim the exploration of subjectivity. The deep/surface dichotomy was not found in this study, but rather three unique types of study approaches. Moreover, though Q Methodology, new novel combinations of statements were able emerge and thus allowing the academic discussion to move beyond the deep and surface dichotomy.

KEYWORDS:

• Approaches to studying
• higher education
• oppositional dichotomies
• Q Methodology

Introduction

Student learning approaches’ research has been built upon the notions of deep and surface learning and these notions are ‘one of the most widely used in relation to teaching in higher education’ (Tormey 2014, 1). The foundations of deep/surface approaches stem largely from the work of Marton and Säljö (1976a, 1976b). When students employ a deep approach, understanding and meaning is constructed from that activity. Contrarily, memorizing facts characterizes a surface approach. Webb (1997) has asserted that deep and surface approaches have become the ‘canon for educational development’ (195). Numerous studies have been conducted looking at learning approaches as related to: study manners (Entwistle et al. 1979; Morgan, Taylor, and Gibbs 1982), perceived academic quality (Richardson, Gamborg, and Hammerberg 2005; Richardson et al. 2007), and potential differences among various student characteristics (Entwistle, Tait, and McCune 2000; Cuthbert 2005).

Despite its status as part of the educational research canon, deep/surface approaches have been critiqued as constraining the debate surrounding student learning. As Haggis (2003) noted ‘the widespread and usually unquestioning use of this model imposes limitations on the way that research data about student learning are both generated and understood’ (95). Haggis critiques the status of deep/surface approaches as a normative paradigm (95), shrouding any opposite points of view while reinforcing research that supports its own foundations. Tormey (2014) raises concerns about deep/surface approaches functioning as both a metaphor and valid concept. This duality, according to Tormey, ‘is now obscuring the ways in which the empirical work could contribute to a better understanding of teaching and learning' (2014, 2).

Malcolm and Zukas (2001) have noted that the literature on teaching and learning in higher education is ‘dominated by explicitly psychological versions (particularly humanistic and cognitive models) of the learner and teacher’ (34). These versions generally create a view of the learner that is devoid of any history or culture, thus eliminating a key element in the construction of knowledge; ‘our history and culture precede and construct our self-understandings, our self-consciousness' (39).

Richardson (2004) has raised reliability and validity concerns about revised approaches to studying inventory (RASI) (Entwistle et al. 1979) and the Student process Questionnaire (SPQ) (Biggs 1982). Reliability concerns centered on the variability in both the internal consistency of the constituent scales and test–retest consistency. The issue of content validity is raised from the point of situational and contextual differences and notes that ‘culture’ as a concern in the interpretation of approaches to studying (Richardson 1994). However, his critique is not based upon a devoid dichotomy as Malcolm and Zukas notes, but rather that approaches to studying ‘vary systematically from one culture to another' (2001, 449). Additionally, Mogashana, Case, and Marshall (2012) report inconsistent or contradictory inventory responses in students’ responses during the academic year for the same course.

The notion of dissonant study orchestrations (Meyer, Parsons, and Dunne 1990) where a student reports a combination of meaning and reproductive orientations, has also been identified and may be partly attributed to a tension between the demands of the learning environment and students’ study practices and individual goals (Lindblom-Ylänne and Lonka 2000).

However, as Webb (1997) remarked, ‘the longevity of the deep/surface metaphor may be linked to … the universality and power of the metaphor’ (196). Nonetheless, in the light of a complex educational reality, this dichotic metaphor has been explicitly rejected by the addition of a third factor ‘strategic’ studying inventories such as the RASI (Ramsden 1979). Moreover, this metaphor is occasionally found in the research, evidenced by several studies using the RASI that reveal combinations of deep and surface factors (Entwistle et al. 1979; Price, Richardson, and Jelfs 2007; Remedios and Richardson 2013).

The simplicity of the ‘oppositional dichotomy’ within the deep/surface model can be found in other models describing student learning approaches. Historically, these models also resulted in ‘bipolar typologies’ such as Svensson's ‘holistic-atomistic’ and Pask and Scott's ‘holist-serialist’ (Bessant 1995, 330). These dichotomies are also oppositional in nature. Clarke (2006) presents a powerful argument against oppositional dichotomies in education and specifically for ‘teaching and learning’(378) and ‘teacher-centered’ and ‘student-centered’ (2006, 381). Contained in such dichotomies, is the offering of ‘falsely exclusive choices’ (Clarke 2006, 385); one is either a teacher or learner, one's teaching style is either ‘teacher-centered’ or ‘student-centered'. Akin to Clarke's critique of ‘teacher-centered’ and ‘student-centered’ is the current framing of the concepts of deep and surface as being mutually exclusive. It is ‘language’ itself that restricts the understanding of a phenomenon through ‘socially encoded and constructed discursive practices that mediate reality so much so that they effectively close off direct access to it' (Munslow 1997, 11). Clarks adds: ‘our theories are framed in language that inevitable constrains both the identification and the description of certain relationships’(2006, 378).

These ‘falsely exclusive choices’ can be seen in Gordon and Debus (2002) call to ‘abandon surface learning approaches and adopt deeper learning approaches’ (484). Indeed, deep approaches to studying have been linked with ‘high quality learning outcomes’ (Gordon and Debus 2002) and perceived academic quality (Richardson et al. 2007). However, the relationship between approaches to studying and academic performance is tenuous, at best, presenting unclear and sometimes contradictory research outcomes. For example, Choy, O'Grady, and Rotgans (2012) reported the SPQ as a weak indicator for academic achievement, Kember et al. (1995) reported ‘deep approach does not result in good grades unless accompanied by sufficient work' (329).

Research questions

1. Is there evidence of distinctly different deep and surface study approaches?

2. Are there new unique combinations of study approaches?

Method

Q methodology

Q Methodology was used as both a research method and an analytical technique for this study and aims to the explore subjectivity (Stephenson 1953). As McKeown and Thomas state (2013): ‘The primary purpose for undertaking a Q study is to discern people's perceptions of their world from the vantage point of self-reference' (1). Subjectivities have been researched surrounding topics such as: prioritizing health care resources (van Exel et al. 2015), implications of divorce on children's emotional and behavioral well-being (Øverland, Størksen, and Thorsen 2013), experiences of transient ischaemic attack (Spurgeon et al. 2012), and human resource development (Bartlett and DeWeese 2015).

In this study, students’ perceptions of their study approaches will be the vantage point. Statements used in Q Methodology are called the ‘Q-Set’ and are generally created from the dominant discourse surrounding the topic being investigated. Participants then sort the Q-Set using a sorting sheet that has as answer anchors such as ‘most disagree’ to ‘most agree’ and are placed within a quasi-normal distribution framework. By collecting data in this fashion, participants are presented the opportunity to ‘create’ unique combinations and relations of answers. The individual Q-Sorts are then subjected to factor analysis. Q-Sorts that are correlated represent similar viewpoints or ‘segments of subjectivity which exist’ (Brown 1993, 94).

Participants

A convenience sample of 65 students enrolled in a full-time accounting master's program was used for this study. Sixty-two fully completed Q-Sorts were returned and used in the analysis.

Q-Set (statements) development

The creation of a Q-Set has been described as ‘collection of self-referable statements about something, of statistical dimensions’ (Stephenson 1993, 5). Stephenson (1953) also calls for a balanced collection of statements to form the Q-Set. Stephenson (1953) advises ‘to find a few simple principles which, on a prima facie basis, seem to be involved’ (7). The starting point for the development of the Q-Set was the Approaches to Studying Inventory (ASI) (Tait and Entwistle 1996) due to this instrument's long use in research as well as, its central concepts, deep/surface approaches continue to function as a ‘normative paradigm’ (Haggis 2003, 95). This inventory consists of 52 items.

In cooperation with the one of the original authors of the ASI, a Q-Set containing 36 statements were selected for this study (Entwistle, personal communication, April 22, 2014). Twelve items per ‘approach’ (deep, strategic, and surface) were selected.

Q-Sort

Participants were instructed to first read all of the 36 Q-Set statements and then pre-sort these statements ‘disagree, neutral, or agree'. Once this stage was completed, participants filled in the Q-Sort (Figure 1) with the corresponding statement number using the pre-sorting as a rough guide.

Figure 1. Representation of Q-Sort used in this study.

Results

Factor extraction

To determine participants with similar ‘viewpoints', a factor analysis using a manual rotation was performed using PQMethod v2.35. Factors in Q Methodology represent a cluster of participants and not individual items. Three factors were revealed with 52 participants having a significant factor loading on one factor ( > .40 factor loading): (factor 1 and factor 2, rotation angle = –35, factor 1 and factor 3, rotation angle = –26, factor 2 and factor 3, rotation angle = –10).

Factor arrays

In order to interpret the three factors, an idealized Q-Sort was constructed for each of the three factors. This is accomplished by calculated standardized factor score (z-score) per question per factor. These scores are based upon the individual participant's statement score weighted by their factor loading on that factor. This procedure differentiates the strength of individual participant's scores when calculating the ranking order of statements for that factor. Accordingly, the statement with the highest z-score for a factor would be assigned a ‘ + 5' and subsequent questions’ factor scores were labeled. This idealized Q-Sort ranking is used to sequentially return all statements into the Q-Sort's quasi-normal distribution framework. Additionally, statements’ factor scores were also tested for significant (p < .01) differences. Questions exceeding this limit were labeled as ‘distinguishing statements’ for that factor (Table 1).

Table 1. Statements and factor array.

Statement	Factor array
	1	2	3
When working on an assignment, I'm keeping in mind how best to impress the marker	−1	−1	1
Often I find myself wondering whether the work I am doing here is really worthwhile	−1	1	−4
I usually set out to understand for myself the meaning of what we have to learn	4	2	2
I find I have to concentrate on just memorizing a good deal of what I have to learn	−1	3	−1
Often I feel I'm drowning in the sheer amount of material we're having to cope with	−5	−1	−2
I look at the evidence carefully and try to reach my own conclusion about what I'm studying.	4	0	1
It's important to me to feel that I'm doing as well as I really can on the courses here	−1	0	2
I try to relate ideas I come across to those in other topics or other courses whenever possible	3	0	2
I tend to read very little beyond what is actually required to pass	0	4	−2
Regularly I find myself thinking about ideas from lectures when I'm doing other things	1	−4	1
I think I'm quite systematic and organized when it comes to revising for exams	−1	5	5
I look carefully at tutors’ comments on course work to see how to get higher marks next time	0	−2	4
There's not much of the work here that I find interesting or relevant	−2	−2	−4
I'm pretty good at getting down to work whenever I need to	1	0	1
Much of what I'm studying makes little sense: it's like unrelated bits and pieces	−4	−3	−3
When I'm working on a new topic, I try to see in my own mind how all the ideas fit together	3	1	0
I often worry about whether I'll ever be able to cope with the work properly	−3	−4	−3
Often I find myself questioning things I hear in lectures or read in books	2	−1	−1
I'm good at following up some of the reading suggested by lecturers or tutors	0	−5	−1
When I look back, I sometimes wonder why I ever decided to come here	−4	−3	−5
When I am reading I stop from time to time to reflect on what I am trying to learn from it	2	1	−1
I work steadily through the term or semester, rather than leave it all until the last minute	−3	−1	3
I'm not really sure what's important in lectures, so I try to get down all I can	−3	−3	−2
Ideas in course books or articles often set me off on long chains of thought of my own	1	−2	−1
When I read, I examine the details carefully to see how they fit in with what's being said	2	1	0
I put a lot of effort into studying because I'm determined to do well	1	1	4
I gear my studying closely to just what seems to be required for assignments and exams	0	3	0
Some of the ideas I come across on the course I find really gripping	0	0	2
I usually plan out my week's work in advance, either on paper or in my head	−2	2	3
I keep an eye open for what lecturers seem to think is important and concentrate on that	1	3	1
I'm not really interested in this course, but I have to take it for other reasons	−2	−1	−2
I generally make good use of my time during the day	0	2	0
I often have trouble in making sense of the things I have to remember	−2	−2	−3
I like to play around with ideas of my own even if they don't get me very far	2	0	0
It's important for me to be able to follow the argument, or to see the reason behind things	5	2	0
I don't find it at all difficult to motivate myself	3	4	3

Factor 1: the ‘critical reflector’

Eleven students (21%) loaded significantly for factor 1and is exemplified by searching for meaning and understanding of the material. The relating of new information to their previous knowledge is also present in this approach. Additionally, there is an element of critical reflection, since these students report examining the evidence before reaching their conclusions. There is also an element of intellectual curiosity found in this factor. Students who loaded on this factor reported that they ‘try and see in my own mind how all the ideas fit together’ and that they like to ‘play around with ideas'. They also seem to take the time to reflect on the new ideas encountered when studying. Even with this conceptual reflection approach, there are elements in this factor that could raise concerns: reported lack of planning and not steadily working during the semester. It could be that these students begin to study and are so engaged in trying to understand the material that planning their studies and steadily working on their course material is not in focus. Additionally, these students could be so engrossed in their search for understanding that they may fail to fully take into account the formal assessment requirements of that course (Table 2).

Table 2. Distinguishing statements factor 1.

Statement	Factor array
	1	2	3
Agree
It's important for me to be able to follow the argument, or to see the reason behind things^D	5*	2	0
I usually set out to understand for myself the meaning of what we have to learn^D	4*	2	2
I look at the evidence carefully and try to reach my own conclusion about what I'm studying^D	4*	0	1
When I'm working on a new topic, I try to see in my own mind how all the ideas fit together^D	3*	1	0
I like to play around with ideas of my own even if they don't get me very far^D	2*	0	0
When I am reading I stop from time to time to reflect on what I am trying to learn from it^D	2*	1	−1
Disagree
I usually plan out my week's work in advance, either on paper or in my head^ST	−2*	2	3
I work steadily through the term or semester, rather than leave it all until the last minute^ST	−3*	−1	3
Often I feel I'm drowning in the sheer amount of material we're having to cope with^SF	−5*	−1	−2

Note: ^D, deep item; ^ST, strategic item; and ^SF, surface item.

*Significance = .01 level.

When interpreting this factor from the traditional standpoint of deep/strategic/surface approaches to studying, this factor is characterized by an emphasis on a deep approach and lack of a strategic study approach. What is noteworthy, is the lack of ‘surface approach’ statements contained within the ‘Disagreement’ statements.

Factor 2: the ‘curricular minimalist’

Eighteen students (34%) loaded significantly on factor 2, which is exemplified by a focused and targeted study approach that emphasizes the formal curricular requirements and reliance upon signals from the lecturers. This study approach is focused on passing the exam through discovering assessment clues contained in the required curriculum (i.e. syllabus) as well as, signals from the lecturers. The first statement ‘I think I'm quite systematic and organized when it comes to revising for exams’ is not a statistically distinguishing statement among these three factors. However, its placement as the most ‘agreed’ in the factor array (for both factors 2 and 3) signifies the prominence of the effect exams have on the study approaches of these students. Examining this factor without taking this into account would neglect the key focal point for these students: passing the exam.

This study approach is, constrained by both the required readings and the students’ keen eye for perceived potential assessment clues from teaching staff. Students’ focus and effort is strongly and preemptively focused toward passing exam and not on explicitly on learning. This is evident in the combination the highest positively loaded statements contained in this factor. A depiction of a student arises of one who is only trying to pass the course. This is evidenced by an approach characterized by ‘little beyond what is actually required to pass, just memorizing, required for assignments and exams, and for what lecturers seem to think is important'. But this notion is also supported by the reported lack of critical thought given to ‘tutors’ comments on course work’ in order to improve their grade. This seems to suggest a non-focus on improving their learning and grades, but being able to pass the course the first time (Table 3).

Table 3. Distinguishing statements factor 2.

Statement	Factor array
	1	2	3
Agree
I think I'm quite systematic and organized when it comes to revising for exams^ST	0	5	5
I tend to read very little beyond what is actually required to pass^SF	0	4*	−2
I find I have to concentrate on just memorizing a good deal of what I have to learn^SF	−1	3*	−1
I gear my studying closely to just what seems to be required for assignments and exams^SF	0	3*	0
I keep an eye open for what lecturers seem to think is important and concentrate on that^ST	1	3*	1
I usually plan out my week's work in advance, either on paper or in my head^ST	−2	2*	3
I generally make good use of my time during the day^ST	0	2*	0
It's important for me to be able to follow the argument, or to see the reason behind things^D	5	2*	0
Disagree
I look carefully at tutors’ comments on course work to see how to get higher marks next time^ST	0	−2*	4
Ideas in course books or articles often set me off on long chains of thought of my own^D	1	−2*	−1
Regularly I find myself thinking about ideas from lectures when I'm doing other things^D	1	−4*	1
I'm good at following up some of the reading either on paper or in my head^ST	0	−5*	−1

Note: ^D, deep item; ^ST, strategic item; and ^SF, surface item.

*Significance = .01 level.

When interpreting this factor from the traditional standpoint of deep/strategic/surface approaches to studying, this factor is characterized by a combination of strategic and surface approach statements. Noteworthy is that one deep approach statement was distinguishing. If we interpret this statement as representing a purely conceptual approach, then this statement does not to fit well with the other distinguishing statements. However, if we contextually interpret this statement, the motivation to follow the argument is not one of intellectual curiosity as this statement is generally assumed to represent, but a searching for the argument or reasoning in order find clues for this course's assessment demands. The disagreement statements also contain a combination of approaches having a grouping of deep and strategic approach statements.

Factor 3: the ‘determined worker’

Twenty-three students (44%) loaded significantly on factor 3, which is exemplified by a strong sense of planning and determination to do well in the course. As with factor 2, the statement ‘I think I'm quite systematic and organized when it comes to revising for exams’ is not a statistically distinguishing statement among these three factors. But, its placement as the most ‘agreed’ in the factor array (for both factors 2 and 3) signifies, once again, the prominence of the effect exams have on the study approaches of these students. Taking this into consideration, students’ study approach is focused on passing the exam, but contrary to factor 2, their approach is based on systematic effort and determination and not finding assessment clues. These students do take the comments of tutors into consideration in order to improve their marks. However, the focus is on ‘doing as well as I really can’ since they ‘determined to do well’ and not explicitly concentrated on the materials or an understanding thereof. These students report finding the work they are doing more ‘interesting or relevant’ compared to the other two factors and have a higher sense that their work is ‘really worthwhile’ compared to the factor 1 (–1) and factor 2 (1) (Table 4).

Table 4. Distinguishing statements factor 3.

Statement	Factor array
	1	2	3
Agree
I think I'm quite systematic and organized when it comes to revising for exams^ST	0	5	5
I look carefully at tutors’ comments on course work to see how to get higher marks next time^ST	0	−2	4*
I put a lot of effort into studying because I'm determined to do well^ST	1	1	4*
I work steadily through the term or semester, rather than leave it all until the last minute^ST	−3	−1	3*
It's important to me to feel that I'm doing as well as I really can on the courses here^ST	−1	0	2*
Disagree
Often I feel I'm drowning in the sheer amount of material we're having to cope with^SF	−5	−1	−2*
I tend to read very little beyond what is actually required to pass^SF	0	4	−2*
Often I find myself wondering whether the work I am doing here is really worthwhile^SF	−1	1	−4*
There's not much of the work here that I find interesting or relevant^SF	−2	−2	−4*

Note: ^D, deep item; ^ST, strategic item; and ^SF, surface item.

*Significance = .01 level.

When interpreting this factor from the traditional standpoint of deep/strategic/surface approaches to studying, this factor is characterized by an emphasis on a strategic approach with disagreement statements containing only surface approach statements.

Consensus statements

Statements can also be examined in terms of consensus and disagreement. This is performed by analyzing the variance across the questions’ factor z-score. The lower the variance, the higher the level of consensus that statement has among the three factors. Oppositely, the higher the variance the lower the level of consensus that statement has among the three factors. By examining the consensus statements, a common viewpoint in reported perspective (subjectivity) can be discovered.

In three factors, students reported no difficulties in motivating themselves. Noteworthy is that the focus of each of the three factors is quite different; factor 1; searching for meaning and understanding, factor 2; discovering clues to pass, factor 3; systematic effort to pass. In other words, these students reported being capable of motivating themselves, however toward three differing outcomes. Additionally, students reported that they are able to sufficiently cope with the current course load and that there is a perceived continuity in the curriculum; it is not ‘like unrelated bits and pieces' (reverse question). Additionally for lecturers in this course, students report getting a sense of the important points during lectures, and not having to try and ‘get down all I can'. For teaching staff, these two perceptions held by students, might indicate a well-developed, logical, and organized course (Table 5).

Table 5. Consensus statements (variance across factor z-scores).

Statement	Factor array
	1	2	3
Agree
I don't find it at all difficult to motivate myself^ST	3	4	3
Disagree
I often worry about whether I'll ever be able to cope with the work properly^SF	−3	−4	−3
I'm not really sure what's important in lectures, so I try to get down all I can^SF	−3	−3	−2
Much of what I'm studying makes little sense: it's like unrelated bits and pieces^SF	−4	−3	−3

Discussion

Distinctly different deep and surface study approaches?

The deep/surface dichotomy was not found in this study, but rather unique combinations of deep and non-strategic (factor 1), strategic/surface and non-deep (factor 2), and strategic and non-surface (factor3). Factor 1 offers a unique insight for exploring this dichotomy. This factor's agreement statements were all deep approach statements. In support of a deep/surface dichotomy, one would expect to see the disagreement statement being comprised of surface approach statements. This is not the case. For factor 1, there appears to be a tension between conceptual intellectual studying and a lack of a strategic method of working which may lead to failing to fully take into account the formal assessment requirements of that course. This might be a potential explanation for the lack of a clear relationship between deep approaches to studying and academic performance.

Unique combinations of study approaches?

Factor 2 combines four strategic, three surface, and one deep approach agreement statements. These students display a study approach that combines strategic elements such as: attentiveness to assessments, organized study, and time management with the surface aspects such as; rote memorization and keeping within the boundaries of the curriculum. Students adopt this study approach in order to pass the exam. The sole deep statement ‘It's important for me to be able to follow the argument, or to see the reason behind things' is generally assumed to represent an intellectual engagement with the material, however, in this context, the more likely interpretation of this statement is the adoption of a study approach in order to find clues for this course's assessment demands by ‘following the argument'.

Different meanings depending on the context?

As discussed in the previous section, a deep approach statement in an otherwise strategic/surface approach must be interpreted differently than if it was contained in a pure deep approach factor. This point is highly noteworthy.

An additional point needed to be discussed is the interpretation of ‘disagreed' statements. For example, the surface approach statement ‘Often I find myself wondering whether the work I am doing here is really worthwhile' as found in factor 3. This statistically disagreed distinguishing statement generally represents a surface approach and more specifically a lack of purpose. However, in this study, students disagreed with this statement. The eventual categorization of this negative statement raises many issues: Should this item be considered a deep approach statement? Is a sense of purpose characteristic of a deep approach? Or should a new study approach ‘non-surface' be advised? As discussed above, the distinguishing agreement statements for factor 1 are comprised of only deep approach statements opposed by two strategic and one surface distinguishing disagreement statements such as: ‘I usually plan out my week's work in advance, either on paper or in my head' and ‘I work steadily through the term or semester, rather than leave it all until the last minute.' However, these statements do not form a theoretical opposition to the deep approach statements contained in factor 1′s distinguishing agreement statements. In other words, planning and continual studying are not theoretical opposed to a deep study approach but these statements are in opposition to a deep study approach in this factor.

If one holds the paradigm that deep and surface study approaches form an oppositional dichotomy, then the categorization the study approaches found in this study will remain elusive. When operating within this paradigm, disagreed deep approach statement, must be accepted as a valid representation of a surface study approach. Equally, if a surface approach statement is disagreed with, then one must accept that it as a valid representation of a deep study approach. However, this is simply not the case. What do these statements come to represent? What is the theoretical opposite for a strategic approach? While Tormey contends that ‘the centre cannot hold' (2014, 1) typified by the tension between deep/surface approaches functioning as both a metaphor and valid research concept, I contend that the perceived center created by a simple dichotic deep and surface model also cannot hold.

Additionally, it is my assertion that the nature of statements (i.e. deep, surface, or strategic) must be able to lose their specific exclusiveness in representing a certain study approach when participants combine these statements within a specific context. By doing this, opportunities are created to understand study approach statements in unique combinations for that specific cluster of students holding a certain vantage point of self-reference. Additionally, by accepting this assertion, the academic discussion can move beyond the deep and surface dichotomy.

Disclosure statement

No potential conflict of interest was reported by the author.

ORCID

Brian P. Godor http://orcid.org/0000-0003-3070-3404