Evidence of the existence of noctcaelador across three measures: a factor analytic study.

This study factor analytically examined the convergence of three questionnaires used in previous research to measure night-sky related attitudes and behaviors in a sample of 72 college students. One factor emerged accounting for the majority of variance in responses. It was concluded that the single factor found across separate measures used in previous research appear to assess the higher-order construct known as noctcaelador.

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Through factor analysis, previous research has indicated that a single latent construct accounts for the majority of the variance in students' night-sky watching attitudes, interests, and self-reported behaviors (Kelly, 2003; Kelly & Kelly, 2003). Kelly (2003) termed this construct noctcaelador and defined it as a psychological attachment to the night-sky. Previous studies examining individual differences correlates of one noctcaelador measure, the Noctcaelador Inventory (Kelly, 2004a), among student samples have found the construct to be related to habitually attaining less sleep (Kelly & Rose, 2005), artistic and investigative vocational interests (Kelly, 2005), openness to experience (Kelly, 2004b), and a preference for spending time outdoors (Kelly & Kelly, 2005). Outside of this limited knowledge, however, little is known about noctcaelador. Further knowledge of the topic might assist educators and researchers interested in better understanding students with an interest in night-sky related phenomena.

One limitation of existing research on noctcaelador is the lack of evidence to substantiate the existence of the construct. In the absence of a theory for the construct, perhaps one method to assist in its substantiation is to empirically evaluate the convergence of measures used in previous studies. One measure used in previous research is the Noctcaelador inventory (NI; Kelly, 2004a). The NI is a psychometrically sound 10-item instrument developed from a pool of 33-items measuring different aspects of night-sky related psychological phenomena, i.e. behavior and attitudes.

Earlier studies which found evidence of the existence of the noctcaelador construct (Kelly, 2003; Kelly & Kelly, 2003) used measures other than the NI which examined different aspects of night-sky watching. For instance, Kelly (2003) used five items primarily assessing night-sky watching attitudes. Kelly and Kelly (2003), on the other hand, used five items primarily assessing night-sky watching behaviors. Analyses in each study found that each of the three scales used to assess noctcaelador thus far have had unidimensional factor structures. Each study, however, factor analytically evaluated different measures assessing different dimensions of night-sky attitudes and behaviors. Thus, there is no existing evidence to indicate whether or not the measures used in these three studies tap the same construct. Such evidence could be important in providing support for the existence of a higher-order noctcaelador construct and the generalizability of previous studies using different measures. The purpose of this study, therefore, was to determine whether or not the measures used in each of these studies indeed assessed a single higher-order construct.

Method

After obtaining informed consent, 72 college students (M age = 28 years, SD = 8.3; 86% female; 89% White), enrolled in undergraduate psychology courses completed the 10-item Noctcaelador Inventory (NI; Kelly, 2004a; _ in this study = .94), five items used by Kelly (2003) assessing general attitudes and interest in the night-sky (_ = .86), and the five items used by Kelly and Kelly (2003) assessing self-reported night-sky watching behaviors and related decision-making (_ = .83). The response format of the latter two measures was altered from that used in previous studies to a 5-point scale consistent with that of the NI, whereby 1 = a negative response (i.e., strongly disagree, never, definitely no) and 5 = a positive response (i.e., strongly agree, very often, definitely yes).

Results and Discussion

A principal components factor analysis was calculated on responses to all 20 items used in this study. Three factors emerged with eigenvalues greater than 1 (eigenvalues were 11.1, 1.3, and 1.2 for Factors 1,2 and 3, respectively). Results of a scree plot indicated that only Factor 1, which accounted for 55.4% of the variance, should be retained. All items loaded above .50 on factor 1 (loadings ranged between .52 and .85). Further, total scores on each scale were entered into a principal components analysis. One factor emerged which accounted for 85.3% of the common variance (eigenvalue = 2.6).

These results provide support for the external validity of previous research, i.e., the same construct was being tapped by separate measures in each study. Moreover, the questionnaires used in this study covered night-sky related behaviors, interests, atitudes, decision-making, childhood recollections of watching the night-sky, and positive reactions to the night-sky. This is perhaps a sufficiently wide range of content to suggest that the single observed factor demonstrates enough divergence and structural convergence to suggest the influence of a higher-order night-sky related psychological construct--i.e., noctcaelador. Future research is needed to continue to examine the possible influences that noctcaelador has on behaviors and relations with other individual differences measures.

Correspondence concerning this article should be addressed to William Kelly at [e-mail].

References

Kelly, W. E. (2003). Night-sky watching attitudes among college students: A preliminary investigation. College Student Journal, 37, 194-196.

Kelly, W. E. (2004a). Development of an instrument to measure noctcaelador: Psychological attachment to the night-sky. College Student Journal, 38, 100-102.

Kelly, W. E. (2004b). The "OCEAN" and the night-sky: Relations between the five-factor model of personality and noctcaelador. College Student Journal, 38, 406-408.

Kelly, W. E. (2005). An investigation of vocational interests and noctcaelador. Journal of Instructional Psychology, 32, 164-166.

Kelly, W. E., & Kelly, K. E. (2003). Further identification of noctcaelador: An underlying factor influencing night-sky watching behaviors. Psychology and Education: An Interdisciplinary Journal, 40, 26-27.

Kelly, W. E., & Kelly, K. E. (2005). Noctcaelador and preference for spending time outdoors. Psychology and Education: An Interdisciplinary Journal, 42, 40-42.

Kelly, W. E., & Rose, C. (2005). Losing sleep to watch the night-sky: The relationship between sleep-length and noctcaelador. College Student Journal, 39, 45-47.

William Kelly, Department of Social Sciences, Robert Morris University.