Cross, Bacon and Morris (2000) designed a scale to measure interdependent relational self-construal, which is “a general orientation toward representing oneself in terms of close relationships” (p. 793). These researchers suggested that "the person who is low in interdependence may not be as likely to consider other people's wishes or reactions or to consult other people for information or advice" (p. 799).
Based on Cross et al.'s (2000) suggestion, my colleagues and I have developed a general purpose measure of dispositional preferences for independent and interdependent problem-solving called the Independent-Interdependent Problem-Solving Scale (IIPSS; pronounced "ipsus"; Rubin, Watt, & Ramelli, 2012). Independent problem-solvers prefer to work on their own when solving problems. In contrast, interdependent problem-solvers prefer to consult with other people.
Version 2 of the IIPSS is displayed below. Compared to Version 1, this second version is slightly shorter and has more concise instructions. Participants respond to each item using a 7-point Likert-type response scale anchored Strongly Agree and Strongly Disagree.
Problem-SolvingPlease indicate how much you agree or disagree with each of the following statements:
1. When faced with a difficult personal problem, it is better to decide yourself rather than to follow the advice of others.
2. I value other people’s help and advice when making important decisions.
3. In general, I do not like to ask other people to help me to solve problems.
4. I prefer to make decisions on my own, rather than with other people.
5. I like to get advice from my friends and family when deciding how to solve my personal problems.
6. I prefer to consult with others before making important decisions.
7. I usually find other people’s advice to be the most helpful source of information for solving my problems.
8. I would rather struggle through a personal problem by myself than discuss it with a friend.
9. I do not like to depend on other people to help me to solve my problems.
10. I usually prefer to ask other people for help rather than to try to solve problems on my own.
Five of the items measure the preference for independent problem-solving (items 1, 3, 4, 8, & 9), and five measure the preference for interdependent problem-solving (items 2, 5, 6, 7, 10). Two of the items were taken from Triandis et al.'s (1986) Individualism-Collectivism scale (items 1 & 8), and one was based on Oyserman, Coon, and Kemmelmeier (2002, p. 9; item 6). The remaining items were generated by myself.
Researchers should reverse code participants’ responses to either the independent problem-solving items or the interdependent problem-solving items and then compute the average score of all 10 items. The decision about which set of items to reverse code depends on whether researchers would like to represent independent problem-solving with high scores and interdependent problem-solving with low scores or vice versa.
Reliability and Validity
Rubin et al. (2012) reported evidence of the reliability and validity of Version 1 of the IIPSS. In summary, the scale has good reliability, with a single factor structure (eigenvalue = 3.96) and good internal consistency (αs = .77 & .80). The scale also has good convergent validity. It has small-to-medium sized correlations with Cross et al.’s (2000) Relational-Interdependent Self-Construal scale and Goldberg et al.’s (2006) Extraversion scale. Finally, the scale has good predictive validity. Rubin et al. found that the IIPPSS predicted participants’ self-reported likelihood that they would (a) search the internet to find a solution to a problem at university (i.e., independent problem-solving) and (b) ask another student to help them with a university problem (i.e., interdependent problem-solving).
Analysing the IIPSS
There are two approaches to analysing data from the IIPSS: (1) Treat it as a continuous variable ranging from high independence and low interdependence, through a mixture of both types of problem-solving, to low independence and high interdependence. (2) Designate some cut-off point above and below which you categorize individuals as independent problem-solvers and interdependent problem-solvers.
The continuous approach is the more powerful of the two approaches. As an example, you might include the IIPSS and workplace performance in a correlation or regression analysis and find that the higher individuals' IIPSS scores, the better their performance. If the IIPSS is coded with high scores indicating greater independent problem-solving, then you could conclude that independent problem-solvers perform better than interdependent problem-solvers in that workplace situation. Note that, although we are treating the IIPSS as a continuous variable here, it still makes sense to talk about "independent problem-solvers" and "interdependent problem-solvers" in the same way that it makes sense to talk about "shaven" and "bearded" faces, even though there is no sharp discontinuity between the two (Thouless, 1930).
The categorical approach is less powerful, but often necessary. For example, if you are treating independent-interdependent problem-solving as a moderator variable, and you want to demonstrate that an effect occurs for independent problem-solvers but not for interdependent problem-solvers, then you can split your sample of research participants at one standard deviation above and below the IIPSS mean and compare the effect in each of these two groups (e.g., Aiken & West, 1991). Although it is popular, the problem with this +/- 1 standard deviation approach is that you lose a lot of statistical power because you exclude around 68% of your participants from the analysis. So, for example, with a sample of 100 participants, this approach will result in only around 16 participants in the independent problem-solver group and 16 in the interdependent problem-solver group. To minimize sample loss, you can use a more liberal cut-off point. So, for example, you can use the 25th and 75th percentiles as cut-off points in order to ensure larger numbers of participants in each group (e.g., ns = 25 instead of 16; Hayes, 2013).
In the area of consumer psychology, Vieira (2013) recently found that the IIPSS is related to consumers' need to touch items prior to purchase.
Recent and Ongoing Research
I am currently working with postgraduate student Samineh Sanatkar to examine the moderating effect of independent-interdependent problem-solving on the relation between personality and performance in various social domains.
The IIPSS is free to use for research purposes. No permission is required. However, the scale may not be reproduced for commercial purposes.
Please click here to download a hard copy of the scale for use in paper-and-pencil surveys.
Referencing the IIPSS
The IIPSS was first reported in a journal article that investigated immigrants’ social integration. To refer to the IIPSS, please use the following reference:
Rubin, M., Watt, S. E., & Ramelli, M. (2012). Immigrants’ social integration as a function of approach-avoidance orientation and problem-solving style. International Journal of Intercultural Relations, 36, 498-505. doi: 10.1016/j.ijintrel.2011.12.009
A self-archived version of this journal article is available here.
Cross, S. E., Bacon, P. L., & Morris, M. L. (2000). The relational-interdependent self-construal and relationships. Journal of Personality and Social Psychology, 78, 791-808.
Hayes, A. F. (2013). Introduction to mediation, moderation, and conditional process analysis: A regression-based approach. New York: Guilford Press.
Thouless, E. (1930). Straight and crooked thinking. London: Hodder and Stoughton.