Manuel B. Garcia

Manuel B. Garcia serves as the Senior Director for Educational Technology and Digital Learning at FEU Institute of Technology, Manila, Philippines. Read More

Contact Info

1607, FEU Tech Building,
P. Paredes St, Sampaloc,
Manila, Philippines
mbgarcia@feutech.edu.ph

Follow Me

Why Should Researchers Not Accept AI-Suggested Causal Variables Without Substantive Justification?

Generative AI can propose plausible causal variables, but familiar concepts and convincing explanations do not establish causality. Learn why every suggested variable requires substantive justification before it enters a causal model, research hypothesis, or adjustment strategy.

157
Justifying AI-Suggested Causal Variables Guide 157 of 444
01 · The Question

Why Shouldn't You Trust AI When It Suggests Variables for a Causal Model?

You are investigating whether generative AI use influences students' academic writing performance. You ask ChatGPT which variables should be included in your causal model. It suggests motivation, self-efficacy, digital literacy, prior achievement, institutional support, and socioeconomic status.

The list looks academically credible. Each variable appears relevant to education, and AI can produce a convincing explanation for why it might influence the relationship. You could easily turn the suggestions into a conceptual framework, hypotheses, and regression model.

But what evidence establishes those causal relationships? Are the proposed variables causes, consequences, mediators, confounders, or simply correlated characteristics? And what happens if the model's causal assumptions are wrong?

The central problem is that AI can generate plausible causal stories without demonstrating that the stories accurately represent the phenomenon being investigated.

02 · The Short Answer

Because a Plausible Variable Is Not Necessarily a Causal Variable

In Brief

Researchers should not accept AI-suggested causal variables without substantive justification because a language model's ability to propose plausible relationships does not establish their causal validity, theoretical relevance, or appropriate role in a research design.

Incorrect causal assumptions can lead to inappropriate variable selection, biased statistical adjustment, misleading hypotheses, and unsupported conclusions. Every proposed causal role should be evaluated using theory, prior evidence, temporal reasoning, contextual knowledge, and an explicit causal framework.

03 · What You Need to Know

Why AI-Generated Causal Models Require Independent Scientific Judgment

Language Models Generate Plausible Explanations, Not Verified Causal Structures

Generative AI systems can produce coherent explanations linking familiar concepts. If asked why digital literacy influences AI use, a model may describe how digitally skilled students navigate tools more effectively. If asked why motivation influences academic performance, it may construct another convincing argument.

These explanations can be useful as candidate mechanisms. However, the ability to articulate a plausible causal pathway is not evidence that the pathway operates in the population being studied.

A causal model makes claims about how variables influence one another. Those claims require justification beyond linguistic coherence.

Researchers should therefore distinguish between a causal relationship proposed for investigation and one supported by an appropriate body of theory and evidence.

Causal Roles Are Not Properties of Variable Names

Motivation, self-efficacy, AI literacy, and academic achievement do not have fixed causal roles across studies.

Academic writing confidence might be an outcome in one investigation, a baseline confounder in another, a mediator in a proposed intervention pathway, or an effect modifier under a different model.

Its role depends on the causal question, timing, and assumed relationships among variables.

AI may label a familiar construct as a confounder simply because it appears related to both the exposure and outcome. That classification is not sufficient.

Researchers must examine whether the variable occupies the proposed position in the causal structure and whether that structure is defensible.

Statistical Association Does Not Establish Causal Direction

Suppose students who use generative AI frequently also achieve higher writing scores. This association does not establish that AI use caused the higher performance.

Students with stronger writing skills might be more willing to experiment with AI. Students with greater access to educational resources might both use AI more frequently and perform better. Other explanations may also be possible.

AI can generate these alternatives, but it cannot determine causal direction merely from the observed correlation or the wording of the research question.

Causal inference requires explicit assumptions about the relationships among exposure, outcome, and other relevant variables, together with an appropriate research design.

Substantive Justification Requires More Than a Citation

Researchers sometimes ask AI to justify a variable by supplying supporting references. This can create the appearance of scientific grounding, particularly when the model identifies a familiar theoretical framework or well-known study.

However, a citation does not automatically justify the proposed causal role.

A study showing that motivation is associated with academic achievement does not necessarily establish that motivation confounds the relationship between AI use and writing performance. The required causal relationships may differ from those actually examined in the cited study.

Researchers should inspect what the source investigated, which population and design it used, and what conclusions the evidence supports.

Substantive justification involves explaining why the proposed relationship is plausible in the particular causal model, not simply attaching a reference to a variable name.

A Causal Diagram Is Only as Credible as Its Assumptions

Directed acyclic graphs, or DAGs, can make causal assumptions explicit. They represent variables as nodes and hypothesized causal relationships as directed arrows.

AI can help construct a preliminary DAG from a written explanation. It may also identify possible backdoor paths, mediators, colliders, or adjustment strategies.

However, drawing a DAG does not validate its arrows.

Two researchers may construct different plausible graphs for the same phenomenon because they make different assumptions about temporal ordering, mechanisms, or common causes.

The graph's usefulness depends on the credibility of those assumptions. A mathematically consistent DAG can still misrepresent the real causal structure.

Researchers should examine the relevant literature and substantive context before treating an AI-generated diagram as a basis for causal adjustment.

Incorrect Variable Classification Can Produce Biased Estimates

One of the most serious consequences of unsupported causal assumptions is inappropriate statistical adjustment.

Suppose an AI-assisted writing intervention affects students' confidence, which subsequently influences writing performance. If the researcher seeks the total intervention effect, adjusting for post-intervention confidence may remove part of the effect of interest.

Alternatively, adjusting for a collider can open a noncausal path between exposure and outcome, potentially introducing bias.

These problems cannot necessarily be corrected by increasing sample size or adding more variables to a regression model.

The appropriate adjustment strategy depends on the causal structure and estimand.

This is why identifying potential confounders requires more than selecting variables associated with the outcome.

More Variables Do Not Necessarily Mean a Better Causal Model

Generative AI may recommend including numerous educational and demographic variables to make a model appear comprehensive.

Yet adding variables without justification can increase complexity, reduce statistical precision, introduce problematic adjustment, or change the quantity being estimated.

Some variables may improve prediction without improving causal identification. Others may be consequences of the exposure or share causes with variables already included.

A defensible causal model is not necessarily the one with the most nodes or regression coefficients.

The researcher should be able to explain why each included variable matters to the intended causal question.

Temporal Ordering Can Expose Implausible Causal Claims

Causal explanations generally require attention to when the proposed cause and effect occur.

If AI proposes that students' writing confidence measured after an intervention confounds the intervention's effect on writing performance, the researcher should investigate whether confidence could have been influenced by the intervention.

A post-intervention variable may instead lie on a causal pathway or occupy another role.

Timing alone does not establish causality, but ignoring it can produce incoherent causal models.

AI can help organize a proposed timeline, provided the researcher supplies accurate information about when exposures, outcomes, and other variables were measured.

Theoretical Frameworks Do Not Automatically Establish Every Proposed Arrow

AI often uses established theories to justify relationships among variables. In educational technology, for example, it may invoke technology-acceptance frameworks when discussing perceived usefulness, ease of use, and behavioral intention.

Such frameworks can inform causal hypotheses, but researchers must distinguish relationships explicitly proposed by a theory from extensions that the theory does not directly establish.

A framework developed to explain technology acceptance does not automatically justify causal claims about learning performance, academic integrity, or long-term educational outcomes.

The researcher should explain how the theory applies to the population, setting, constructs, and specific relationships under investigation.

Using a recognized theoretical label does not eliminate the need for substantive reasoning.

AI May Confuse Prediction With Causal Explanation

A variable can improve the prediction of an outcome without being a cause of that outcome.

For example, students' prior grades may help predict writing performance. Whether prior grades should be included as a confounder in a particular causal analysis depends on the underlying causal structure.

Likewise, a predictive model may identify features associated with student success without establishing that changing those features would improve success.

AI-generated recommendations should distinguish predictive usefulness from causal relevance.

Predictive relevance A variable contributes information useful for predicting an outcome under a specified model and data context.
Causal relevance A variable participates in the assumed causal structure in a way that matters to the causal question or identification strategy.

AI-Suggested Mediators and Moderators Need Separate Justification

A model may suggest that motivation mediates an effect while AI literacy moderates it. These claims can sound reasonable because they invoke familiar constructs.

However, mediation concerns a proposed causal pathway, while moderation concerns variation in a relationship or effect across conditions.

Each requires a different substantive argument and potentially different evidence.

Researchers should not accept AI-suggested mediators and moderators without examining their theoretical roles, timing, measurement, and analytical assumptions.

Different Causal Models May Fit the Same Observed Data

Observed associations do not necessarily identify a unique causal explanation.

For example, a positive association between AI use and writing confidence may be compatible with AI use influencing confidence, confidence influencing AI use, or a common cause influencing both.

Different causal structures can sometimes imply the same observed conditional independence relationships. This limits what can be established from observational associations alone.

AI may present one plausible model as though it were the obvious explanation. Researchers should instead consider relevant alternatives and identify what additional assumptions or evidence would distinguish them.

When appropriate, competing research hypotheses can help expose these uncertainties.

Substantive Justification Should Be Documented

When a variable is included in a causal model, the researcher should be able to explain why it is present and what role it is assumed to play.

Documentation may include the relevant theoretical rationale, supporting empirical literature, temporal assumptions, causal diagram, measurement approach, and implications for adjustment.

Where the evidence is uncertain, the researcher should acknowledge competing plausible structures rather than present a single model as established fact.

AI can help organize this documentation, but it should not invent supporting evidence or retrospectively rationalize decisions made solely because a variable appeared in its output.

Substantive Justification Does Not Guarantee Causal Identification

Even a carefully argued causal model may rely on assumptions that cannot be fully verified from the observed data.

Unmeasured confounding, selection bias, measurement error, and model misspecification may remain important limitations.

Researchers should distinguish a plausible causal argument from an identified causal effect.

Where appropriate, sensitivity analyses, alternative designs, or additional data may help examine the robustness of conclusions. However, no amount of polished theoretical explanation can automatically compensate for an inadequate identification strategy.

04 · A Practical Example

Why an AI-Generated Causal Variable List Needs Verification

Hypothetical Example

Studying AI-assisted writing and academic performance

A researcher investigates whether participation in an AI-assisted writing intervention affects undergraduate students' writing performance. AI recommends including motivation, writing confidence, prior achievement, and AI literacy in the causal model.

1. Identify the causal estimand The researcher specifies that the primary interest is the total effect of the intervention on writing performance.
2. Examine the AI-generated suggestions AI labels motivation and prior achievement as confounders, writing confidence as a mediator, and AI literacy as a moderator.
3. Investigate the study design The researcher determines whether intervention assignment is randomized, which variables were measured before assignment, and which may have changed afterward.
4. Evaluate each proposed role Prior achievement might predict performance, but whether it confounds intervention assignment depends on the design. Post-intervention confidence might be a mediator, while baseline AI literacy might be investigated as an effect modifier.
5. Examine the theoretical and empirical basis The researcher reviews relevant studies and theoretical arguments rather than accepting AI's classifications as established causal relationships.
6. Revise the causal model Only relationships that can be substantively defended are retained as working assumptions. Remaining uncertainties are documented and considered when interpreting results.
AI-Suggested Variable Why the Initial Label May Be Inadequate Required Judgment
Motivation Its timing and causal relationships are unspecified Determine whether it precedes exposure, follows exposure, or occupies another role
Prior achievement Prediction of performance does not automatically imply confounding Examine the assignment mechanism and assumed causal structure
Writing confidence Post-intervention confidence may be influenced by treatment Evaluate the proposed mediating pathway and intended estimand
AI literacy A plausible effect modifier is not necessarily an established moderator Justify the expected effect heterogeneity and its measurement

If intervention assignment is genuinely randomized and appropriately implemented, baseline variables generally do not confound the randomized assignment in expectation. Some may still be useful for precision or effect-heterogeneity analysis.

This illustrates why causal variable selection depends on the design rather than a generic list of educational factors. The same suggested variable may have different implications under randomized and observational conditions.

05 · What Researchers Often Get Wrong

Common Errors When Accepting AI-Suggested Causal Variables

Misconception

If AI Provides a Convincing Explanation, the Causal Relationship Is Justified

A coherent explanation is a candidate argument, not empirical evidence. The proposed relationship must be examined against theory, relevant studies, and the research context.

Misconception

A Citation Automatically Validates the Variable's Causal Role

A cited study may establish an association or investigate a different population or relationship. The researcher must verify that the source supports the specific causal assumption being made.

Misconception

More Variables Make a Causal Model More Comprehensive and Accurate

Unnecessary variables can increase complexity, reduce precision, or introduce inappropriate adjustment. The number of variables is not a measure of causal validity.

Misconception

Statistical Significance Determines Which Variables Are Causal

A significant coefficient does not establish causality. Causal roles depend on assumptions and design, not merely on statistical associations.

Misconception

An AI-Generated DAG Is an Objective Representation of Reality

A DAG represents assumed causal relationships. Its arrows require justification, and alternative graphs may be plausible.

Misconception

Once Variables Are Justified, Causal Inference Is Guaranteed

Substantive justification is necessary but does not eliminate unmeasured confounding, selection bias, measurement problems, or other threats to identification.

06 · What This Means for You

Require a Defensible Causal Argument for Every AI-Suggested Variable

Before accepting a variable, ask what causal role it is supposed to play, why that role is plausible, and what evidence supports the assumption. Do not allow AI to treat common educational constructs as universally relevant causal factors.

Use a causal diagram or another explicit framework where appropriate, and distinguish relationships supported by evidence from those that remain assumptions.

A simple decision framework

If AI suggests a new causal variable
Identify its proposed role and the substantive evidence needed to justify inclusion.
If the model labels a variable as a confounder
Examine the assumed causal structure before deciding whether adjustment is appropriate.
If AI proposes a mediator or moderator
Evaluate the relevant mechanism or conditional relationship separately.
If a proposed relationship is supported only by an AI-generated explanation
Treat it as speculative until relevant theory or empirical evidence provides a defensible basis.
If competing causal structures remain plausible
Document the uncertainty and consider whether the design or sensitivity analyses can distinguish their implications.

Researchers should also examine whether AI-generated additions alter the original research question, hypotheses, or intended estimand. A causal model that looks more sophisticated may no longer address the study's actual purpose.

Where necessary, use AI to identify inconsistencies across the research design, but make substantive decisions using the relevant scholarly and methodological evidence.

The guiding principle is simple: AI can propose a causal relationship, but the researcher must be able to defend why that relationship belongs in the study.

07 · A Quick Checklist

Before Including AI-Suggested Variables in a Causal Model

Before accepting a causal variable, check:
Define the causal question and estimand the model is intended to address.
Identify the proposed causal role of every AI-suggested variable.
Verify theoretical arguments and empirical claims using original scholarly sources.
Examine temporal ordering and whether variables may be affected by the exposure.
Distinguish confounders, mediators, colliders, moderators, and predictors.
Evaluate whether proposed adjustment variables are appropriate under the assumed causal structure.
Consider alternative plausible causal diagrams and their implications.
Assess measurement quality, unmeasured confounding, and identification assumptions.
Document the justification and remaining uncertainty for each retained causal relationship.
08 · Frequently Asked Questions

Frequently Asked Questions About AI-Suggested Causal Variables

Why can't I simply use the causal variables ChatGPT recommends?

AI-generated suggestions may be plausible but do not establish causal roles. Including variables without justification can lead to incorrect assumptions, inappropriate adjustment, and misleading interpretations.

What counts as substantive justification for a causal variable?

Substantive justification involves a defensible explanation of the variable's causal role, supported by relevant theory, empirical evidence, temporal reasoning, and contextual knowledge. It should address the specific relationship rather than merely cite a study mentioning the variable.

Can AI identify causal relationships from correlations?

It can propose possible causal explanations, but correlation alone does not establish causal direction or identify a unique causal structure. Additional assumptions and appropriate evidence are required.

Does including more control variables make a causal analysis stronger?

Not necessarily. Some variables may improve precision, while others may introduce bias or change the estimand. Adjustment decisions should follow the causal structure and research question.

Can AI-generated DAGs be used in research?

They may be useful as preliminary representations of causal assumptions, provided every relevant relationship is critically evaluated. The diagram should not be treated as validated simply because AI generated it.

Can a theoretically justified variable still be inappropriate for adjustment?

Yes. A variable may be theoretically relevant but function as a mediator, collider, or other factor that should not be adjusted for when estimating a particular causal effect.

What if the literature does not clearly establish a variable's causal role?

Document the uncertainty, consider alternative plausible causal structures, and examine whether the study design or sensitivity analyses can address the ambiguity. Do not present an uncertain relationship as established fact.

09 · The Bottom Line

A Causal Variable Needs Evidence, Not Just an AI-Generated Explanation

The Bottom Line

Researchers should not accept AI-suggested causal variables without substantive justification because plausible explanations do not establish causal roles, and incorrect assumptions can distort the design, analysis, and interpretation of a study.

Use AI to generate possibilities and challenge assumptions, then verify the relationships through theory, relevant evidence, and explicit causal reasoning. The credibility of a causal model depends on the justification for its relationships, not the sophistication of its diagram or the confidence of the system that proposed them.

10 · Sources and Further Reading

Sources and Further Reading

11 · Cite this Guide

How to Cite This Guide

This guide is intended to be read, shared, and used in research, teaching, and academic work. If you draw on its ideas, explanations, or other content, please acknowledge the source by citing the guide. Doing so gives appropriate credit and helps your readers locate the original resource.

Has the Field Guide helped your research?

If a guide helped clarify a question, inform a research decision, or move your work forward, I would love to hear about your experience. Your story may also help other researchers discover the Field Guide.

Share Your Experience
Takes only a few minutes