Correlation ≠ Causation
One of the most common pitfalls novice evaluators face is mistaking correlation for causation—an error that can lead to misleading conclusions in evaluation reports. While statistical tools like Pearson’s Correlation Coefficient can identify relationships between variables, they do not prove that one causes the other. As humans, we’re naturally wired to spot patterns and assign meaning to them, even when the connection is purely coincidental. To explore this concept, we’ll take a closer look at a humorous yet insightful example: the striking correlation between the number of Bachelor’s degrees in education awarded and Google searches for Nicolas Cage. Using this “spurious correlation,” we’ll first examine the tempting (but flawed) case for causation, followed by a more grounded perspective that highlights why correlation alone isn't enough to draw conclusions.
Source: Vigen, T. (n.d.). Bachelor’s degrees awarded in Education correlates with Google searches for 'Nicolas Cage'. Spurious Correlations. Retrieved April 11, 2025, from https://tylervigen.com/spurious/correlation/13532_bachelors-degrees-awarded-in-education_correlates-with_google-searches-for-nicolas-cage
Part 1
Although a correlation of 0.93 between the number of Bachelor’s degrees in Education awarded and Google searches for Nicholas Cage may initially appear implausible, the relationship warrants closer examination rather than outright dismissal. There are several realistic factors that explain the statistical association. For example, Cage’s involvement in educationally themed films, most notably National Treasure (2004) and National Treasure: Book of Secrets (2007) may have contributed to increased public interest in historical narratives and, by extension, influenced educational pursuits in related fields. Additionally, Cage has publicly expressed a personal passion toward lifelong learning, stating, “I see myself as a student. I’m always looking to learn something” (Hollywood Foreign Press Association, 2021, para. 4). It is likely that these films, which dramatize historical events and problem-solving skills to provide justice, served as internal motivators for individuals considering a career in education, particularly in history. The rise in awarded Bachelor’s degrees in education between 2012 and 2013, peaking in 2013, reflects a measurable impact on these films’ continuous popularity and cultural reach. Whether viewers were inspired to teach history, emulate the films’ protagonists to inspire others, or engage more deeply with education as a means of societal contribution would require further a more targeted evaluation framework.
Part 2
While the high correlation between Bachelor’s degrees awarded in Education and Google searches for Nicholas Cage may appear statistically compelling, inferring causation from this relationship should not be an automatic response. Suggesting that one variable directly influences the other, portrays many assumptions without supportive data. Correlation alone cannot substantial claims of influence without considering other variables. It is entirely plausible that individuals pursuing degrees in education might search for educationally themed media, including films featuring Nicholas Cage, as part of their academic or personal interests. However, this behavior does not establish a direct causal link to Bachelor’s degree attainment. Numerous factors, such as economic trends, cultural trends, influential characters and leaders, and demographic factors can influence educational enrollment patterns and online search behavior. The simultaneous increase in Cage-related search and education degrees awarded could be coincidental or driven by a third, unobserved variable, such as increased media streaming access or a renewed cultural interest in adventure-history genres. Caulfield (2022) explained that the third variable means that a confounding variable affects both variables to make them seem causally related when they are not. Moreover, the use of search engine data for professional actors as a proxy for academic motivation or career decision-making introduces methodological concerns. Google Trends data reflect interest, not necessarily intention, and are influenced by ephemeral factors, like media coverage, memes, and content that is viral. Thus, anchoring an argument stating an education impact is based on the popularity of a celebrity’s Google search is not credible and should be approached with skepticism.
Sources:
Caulfield, J. (2022, May 02). Correlation vs. causation | Difference, examples & fallacies. Scribbr. https://www.scribbr.com/methodology/correlation-vs-causation/
Hollywood Foreign Press Association. (2021, August 11). An evening with Nicolas Cage. Golden Globes. https://goldenglobes.com/articles/evening-nicolas-cage/
Vigen, T. (n.d.). Bachelor’s degrees awarded in Education correlates with Google searches for 'Nicolas Cage'. Spurious Correlations. Retrieved April 11, 2025, from https://tylervigen.com/spurious/correlation/13532_bachelors-degrees-awarded-in-education_correlates-with_google-searches-for-nicolas-cage
Thank you for joining me today! Let’s keep learning altogether, as lifelong #LearningMatters.
Best,
Laura Lawson
LearningMatters, LLC
Instructional Designer
