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  <front>
    <journal-meta>
      <issn pub-type="ppub">1613-0073</issn>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>to Predict Project Quality in Middle School AI Education</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Conrad Borchers</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Xiaoyi Tian</string-name>
          <email>xtian9@ncsu.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kristy Elizabeth Boyer</string-name>
          <email>keboyer@ufl.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Maya Israel</string-name>
          <email>misrael@coe.ufl.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Workshop</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>CSEDM'25: 9th Educational Data Mining in Computer Science Education (CSEDM) Workshop</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Carnegie Mellon University</institution>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>North Carolina State University</institution>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Project-based learning plays a crucial role in computing education. However, its open-ended nature makes tracking project development and assessing success challenging. We investigate how dialogue and system interaction logs predict project quality during collaborative, project-based AI learning of 94 middle school students working in pairs. We used linguistic features from dialogue transcripts and behavioral features from system logs to predict three project quality outcomes: productivity (number of training phrases), content richness (word density), and lexical variation (word diversity) of chatbot training phrases. We compared the predictive accuracy of each modality and a fusion of the modalities. Results indicate log data better predicts productivity, while dialogue data is more efective for content richness. Both modalities modestly predict lexical variation. Multimodal fusion improved predictions for productivity and lexical variation of training phrases but not content richness. These findings suggest that the value of multimodal fusion depends on the specific learning outcome. The study contributes to multimodal learning analytics by demonstrating the nuanced interplay between behavioral and linguistic data in assessing student learning progress in open-ended AI learning environments.</p>
      </abstract>
      <kwd-group>
        <kwd>project-based learning</kwd>
        <kwd>multimodal learning analytics</kwd>
        <kwd>project quality prediction</kwd>
        <kwd>dialogue</kwd>
        <kwd>K-12</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Project-based learning (PBL) is crucial in STEM, especially in computing, where students collaboratively
create artifacts [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
        ]. PBL fosters computational thinking, problem-solving [
        <xref ref-type="bibr" rid="ref3 ref4">3, 4</xref>
        ], and engagement
[
        <xref ref-type="bibr" rid="ref3 ref5">3, 5</xref>
        ]. Efective assessment of student learning and project quality is essential for educators to provide
targeted feedback [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. However, because of the iterative, open-ended nature of project development
(e.g., app creation), tracking progress in PBL is challenging. Analyzing behavioral data during PBL
ofers insights into student learning, collaboration, and refinement strategies. Prior work has explored
predicting project outcomes such as final grades [
        <xref ref-type="bibr" rid="ref7 ref8 ref9">7, 8, 9</xref>
        ], task performance [
        <xref ref-type="bibr" rid="ref10 ref11">10, 11</xref>
        ], group satisfaction
[
        <xref ref-type="bibr" rid="ref12 ref13">12, 13</xref>
        ], and engagement [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. In computer science education specifically, there is a growing interest
in understanding more granular aspects of the project, such as the completeness of the student code
traces [15, 16], or the correctness of the steps within multi-step problem-solving episodes [17]. These
ifner-grained project quality outcomes capture learning progress during PBL, enabling educators and
intelligent systems to identify struggling learners and provide timely support. Predicting project quality
proxies during learning processes (in addition to conventional, post-completion learning outcomes)
can serve two future research purposes: First, it may inform adaptive modules that provide additional
instruction based on detected areas of improvement. Second, it can inform the study of efective student
collaboration by providing insights through models capturing what contributes to desirable learning
process outcomes.
(M. Israel)
      </p>
      <p>CEUR</p>
      <p>ceur-ws.org</p>
      <p>Researchers have explored various data sources and analytical approaches to better understand
and support student learning during PBL. A longstanding tradition in learning analytics involves
inferring cognitive and metacognitive processes from log and language data [18]. While researchers
have leveraged log interactions to model learning trajectories [17, 19], and language data to infer
self-regulated learning strategies [20], these modalities are rarely used for joint prediction. Integrating
dialogue-based and log-based features may ofer a more holistic view of student collaborative learning
analytics [21, 22]. While prior research has focused on predicting learning gains using multimodal
collaboration features [23], less attention has been given to the temporal dynamics of learning [18].
We address this gap by predicting the quality of individual learning events in collaborative learning,
that is, the quality of training phrases while students program a chatbot. Specifically, we compare the
predictive capabilities of dialogue and log data in assessing the quality of student projects in an AI
learning context where students collaboratively develop chatbots. We examine whether combining
diferent modalities of data enhances the predictive accuracy of project quality compared to using them
independently:</p>
      <p>RQ1: How well can student project quality be predicted from single modalities (dialogue, log data)?
RQ2: To what extent does the multimodal fusion of these data sources enhance predictive accuracy?</p>
    </sec>
    <sec id="sec-2">
      <title>2. Related Work</title>
      <sec id="sec-2-1">
        <title>2.1. Multimodal Fusion and Prediction</title>
        <p>Multimodal approaches to mining data and modeling are increasingly common in educational data
mining (EDM) [24, 25]. A recent review by Chango et al. [26] traces emerging trends in the use of
multimodal in typical EDM contexts, including online learning environments, classroom studies, and
blended learning contexts. Data collected in these sites can range from text data to log data, physiological
learner data such as eye-tracking, and spatiotemporal data such as teacher positions [25].</p>
        <p>Natural language data, especially, is increasingly used for foundational EDM prediction tasks. For
example, Zhang et al. [20] utilized large language model (LLM) embeddings to predict self-regulated
learning stages from think-aloud protocols, illustrating the potential of text-based data in understanding
cognitive processes. Scarlatos et al. [27] explored using LLM for knowledge tracing from learners’
dialogue. Borchers et al. [19] fused data from peer tutoring chat collaborations with tutoring system
problem-solving logs to model learning rates in relation to diferent dialogue acts. However, these
approaches have rarely combined language data with log data to jointly model learning.</p>
        <p>The present study builds on this body of work by applying text mining techniques based on automated
transcriptions and embedding [20] with log data for a novel prediction task: predicting learner project
quality in AI education. Specifically, we incorporate transcriptions of students’ collaboration as a data
source in EDM, combining them with established log data to enhance predictive accuracy. By testing the
combined predictive power of log data and transcription-derived features, we test whether multimodal
fusion improves the prediction of learning processes during collaboration. We contribute to the ongoing
discourse on the utility of multimodal data in enhancing educational predictions and insights.</p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. Mining Collaborative Learning Systems</title>
        <p>Collaborative learning systems ofer opportunities to mine multimodal data from learning-system and
learner-learner interactions [28, 29].1 These systems provide insights into learning patterns through
modeling tutoring rates and collaborative behaviors [19], which have been used for feedback tools
[31, 22]. However, selecting meaningful outcomes and learning constructs for multimodal analysis
remains challenging. The present study embraces this challenge in a novel predictive context,
where students learn to program chatbots using natural language inputs. We predict the quality of
1We define collaboration as the coordinated efort to jointly engage in problem-solving and knowledge construction [ 30].
student-created training phrases during learning. Insights from this research have implications for other
collaborative systems and performance prediction from collaborative characteristics [19, 23, 32, 33].</p>
        <p>In addition to peer collaboration interactions, research has demonstrated how dialogue can be
leveraged to support learner-system interactions. For instance, intelligent agents can adapt instruction
based on detected learning patterns [34]. In contrast, teachable agents provide practice problems
and assessments [35] and build rapport with learners through lexical adaptation toward learners
[36]. Similarly, adaptive dialogue systems such as EER-tutor have demonstrated improved learning
gains by considering prior student errors [37]. Finally, Gaze Tutor [38] leveraged gaze data to detect
disengagement and adapt dialogue to re-engage students. The present study builds on this foundation by
seeking to develop meaningful predictors of student learning performance during collaboration, making
progress toward detectors that could improve adaptivity in future collaborative learning systems.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Study Setup and Dataset</title>
      <sec id="sec-3-1">
        <title>3.1. Study Context and Data Collection</title>
        <p>The study was conducted in a public middle school in the southeastern United States in Spring 2024. This
IRB-approved study included 128 students across six class periods in a science class. Out of these, 100
consented to participate in the research, and 97 reported their demographic information: 49 identified
as girls, 46 as boys, one as non-binary, and one preferred not to disclose. Further, 38 students identified
as Asian, 34 as White, 20 as Black/African American, six as Hispanic/Latinx, three as Native American,
ifve as self-described, and three preferred not to disclose. The average age was 11.7 years (SD = 0.48).</p>
        <p>The primary objective of this study was to engage students in core concepts of artificial intelligence
(AI) and computer science (CS) through the hands-on development of conversational agents [39]. The
classroom study contained a 10-hour learning module covering AI fundamentals, hands-on activities,
and chatbot development. The instructional content was aligned with AI Five Big Ideas in K12 [40].
Specific learning goals included (1) understanding the role of data in AI systems and determining
appropriate datasets for specific AI applications; (2) describing how datasets create representations of
the world for reasoning tasks; (3) training and evaluating classification and prediction models while
examining their accuracy on new inputs; and (4) creating chatbots and developing natural interactions.
Each learning module was designed to build students’ AI literacy progressively.</p>
        <p>During collaborative chatbot development, students were randomly paired to create chatbots on
science topics of their choice (e.g., the water cycle, climate, and living organisms). Each pair collaborated
over three class sessions (40 minutes each) to develop their chatbot. We captured audio/video recordings
of these collaborative sessions using recording software from their laptop. Humans transcribed the
recordings through the Rev service. The resulting dialogue dataset contains 121 collaboration sessions
from 47 student pairs (94 individuals). Each session contains an average of 278 utterances (SD = 108.7).</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Chatbot Development Environment</title>
        <p>The learning environment, AMBY (Figure 1), is a graphical interface designed for middle school students
to create conversational agents and learn about AI [41]. The environment enables students to test
example agents, edit agents, or create new agents. For instance, a student group might create an agent on
the topic of “climate change,” where they define intents (e.g., “impact on oceans”), input training phrases
(e.g., “Does climate change impact the oceans?”), and write corresponding responses (e.g., “Climate
change impacts oceans through sea-level rise and ocean acidification.”). Students can test their agents
by having conversations and adjusting the chatbot’s voice to personalize the interaction.</p>
        <p>Students construct and refine intents (i.e., basic chatbot development units representing the goal or
purpose of a user message). In the development panel (Figure 1, left), students can add, edit, or delete
training phrases and responses. They submit training requests by clicking “train the AI,” which updates
the chatbot’s intent classification model based on the provided training data. Students worked with
a partner at the same computer on iterating on the chatbot design, following the pair programming
paradigm [42], prompting spontaneous collaboration, dialogue, and joint decision-making.</p>
        <p>The system collects 23 types of timestamped user interaction logs (e.g., adding or deleting training
phrases, submitting AI training requests, chat messages). Across 121 recorded collaborative sessions,
students submitted an average of seven intent training requests per session, and we used the content of
training phrases they submitted each time as measures of project quality (Section 3.4).</p>
      </sec>
      <sec id="sec-3-3">
        <title>3.3. Dataset Preparation</title>
        <p>To model relationships between system logs, student collaborative dialogue, and project outcomes, we
prepared a multimodal dataset (Figure 2). Following Borchers et al. [18], we synchronized dialogue
transcripts with log data by aligning timestamps between the datasets, yielding an accuracy of 1 second.
For each intent submission, we extracted its submitted training phrases for outcome measurement and
defined intent-working segment, which is the time window from when students began working on
the intent until submission (based on logs). Based on an ad-hoc decision, we manually examined the
segments for accuracy and removed segments that were excessively long (&gt; 12.5 minutes, 90 percentile
of the dataset) based on considerations of context length during embedding. This preprocessing step is
not expected to introduce bias, as our three outcome measures were virtually uncorrelated with dialog
length as measured in the total number of words (| | &lt; 0.05 ) and total number of turns (| | &lt; 0.07 ). The
average segment duration is 193 seconds. We then extracted the synchronized student dialogues and
system logs within these windows for downstream analysis (Section 4).</p>
      </sec>
      <sec id="sec-3-4">
        <title>3.4. Outcome Measures</title>
        <p>Our unit of analysis is the intent, a core chatbot element that handles the recognition of user queries.
Students averaged seven intent training submissions per 30-minute collaborative session and 17 total
submissions. We measured intent quality through three key outcomes chosen based on the learning
objectives, learning curve analyses, and correlation with final project scores.</p>
        <p>Training Phrase Count measures the number of phrases input by students for training the chatbot
to recognize an intent. This metric represents productivity and engagement in the iterative training
process: more phrases typically indicate greater efort in improving the chatbot’s performance. The
relationship between chat-based activity and engagement has also been observed in past research [19].
Lexical Density captures the proportion of content words (nouns, adjectives, verbs, and adverbs) to
total words in the provided phrases, which assesses linguistic richness since efective training requires
substantive content over filler words [ 43, 44]. Lexical Variation measures language diversity through
the ratio of unique content words to total content words [43], important because varied phrases help
chatbots recognize diferent user expressions. Higher variation indicates more robust training input.</p>
        <p>These project quality metrics align with key AI learning objectives [40, 39]. For instance, students
learn that simply adding similar word permutations (i.e., high training phrase quantity with little
information richness, such as ['hat', 'hats', 'HATS']) is inefective for chatbot programming. As
students iteratively generate, refine, and diversify training phrases, they engage in active
problemsolving and knowledge construction [45, 46]. Lexical diversity is also an important predictor of academic
performance in tasks requiring writing and speaking [47, 48].</p>
        <p>Validation. We validated our outcomes through learning curve analyses [49] and correlations
with three final project grades (i.e., expert-rated score aggregated across 11 dimensions using a rubric,
expert-rated training phrase score, and end-user satisfaction evaluated by three independent
annotators). Learning curves can demonstrate whether students improve on our outcome measurements
as they receive indirect feedback from AMBY on their chatbot testing performance. Figure 3 shows
improvements across all metrics over time as students learned to add more phrases and improve lexical
choices in the training data for better intent recognition (with the clearest improvement in lexical
variation). For correlations, while none of our intent-level measures significantly correlated with
overall expert ratings–likely due to the broad scope of the overall assessment, training phrase count
significantly correlated with expert-rated training phrase scores (r(45) = 0.5, p &lt; .001), and lexical density
correlated with end-user satisfaction score (r(45) = 0.36, p = .013), indicating richer linguistic content
improves end-user experience. Our measures showed appropriate separation: moderate correlation
between lexical density and variation ( = 0.28 ) but minimal correlation with training phrase count
( = 0.01 and  = −0.03 , respectively).</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Analysis Methods</title>
      <sec id="sec-4-1">
        <title>4.1. Preprocessing and Feature Engineering</title>
        <p>Log Data Features To capture students’ system interactions during chatbot development, we
engineered log features reflecting engagement, timing, and strategy as inputs for our machine learning
models. We computed timing-related features (six features) capturing temporal dynamics: mean,
standard deviation, minimum, maximum, median, and IQR of time between actions. Event-based
features (2124 features) characterized interaction patterns through event type counts and bigram/trigram
sequences of the 31 unique event types (e.g., [test-chatbot, create-new-intent, add-phrase]).
This approach of using log patterns to predict process outcomes aligns with common EDM methods
where log-based learning rates relate to instructional events [50, 51].</p>
        <p>Language Features in Dialogue Transcripts To capture student dialogue diferences, we computed
numerical representations of student dialogue transcripts within a certain segment using
state-ofthe-art embedding models. Our early experiments showed Sentence-BERT (SBERT) embeddings [52]
from bert-base-uncased performed comparably to OpenAI’s text-embedding-3-large model [53].
Given computational eficiency and open-source considerations, we used SBERT’s 768-dimensional
embeddings as input features for predictive modeling, following established EDM methods [20].</p>
      </sec>
      <sec id="sec-4-2">
        <title>4.2. Model Architecture, Training, and Evaluation</title>
        <p>We employed a feedforward neural network for regression tasks [20], aiming to predict training phrase
quality based on log data features and embeddings. The model architecture consisted of 2-4 hidden
layers with ReLU activations and dropout regularization. Hyperparameters were optimized using grid
search with five-fold student-level cross-validation over the following parameter space: Hidden layer
configurations: [256,128], [512,256,128], [1024, 512, 256,128] and Dropout rates: 0.0, 0.025, 0.05, 0.1, 0.3,
0.5. Model training was conducted using the Adam optimizer, and performance was evaluated using
Mean Absolute Error (MAE) and AUC. Early stopping was implemented with a patience threshold of
two epochs to prevent overfitting. The code is in the study’s digital appendix. 2</p>
        <p>After model training terminated, we evaluated models on a held-out test set (33% of the data),
reporting predictive performance across three feature configurations: log only, dialogue only, and
combined. Using bootstrapped resampling, we computed 95% AUC confidence intervals (CIs). Based
on average cross-validation AUC across folds, the best model was evaluated on the held-out test set.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Results</title>
      <sec id="sec-5-1">
        <title>5.1. RQ1: Can student project quality be predicted from dialogue or log data?</title>
        <p>We evaluated models trained on dialogue data and on log data to predict training phrase quality. Table 1
summarizes the holdout AUC. Training phrase count was better predicted by log-based features (AUC =
0.8053) than dialogue-based features (AUC = 0.5971), suggesting system interaction logs (e.g., frequency
and timing of edits) are stronger indicators of phrase production. Conversely, lexical density was better
captured by the dialogue-only model (AUC = 0.6551 vs. 0.5112), indicating student talk features capture
the richness of their written training phrases. For lexical variation, both models performed modestly
(log: AUC = 0.6016, dialogue: AUC = 0.5260), with log features showing a slight advantage.</p>
      </sec>
      <sec id="sec-5-2">
        <title>5.2. RQ2: Does multimodal fusion improve predictive accuracy?</title>
        <p>To answer RQ2, we performed early fusion, concatenating log, and dialogue features before passing them
to the model [24]. The results are in Table 1 (“combined” rows). Comparing the best single-modality
2https://github.com/conradborchers/collaboration-edm25
results, for training phrase count, fusion improved AUC from 0.8053 (log-only) to 0.8301.3 However,
for lexical density of training phrases, the combined model (AUC = 0.5700) did not outperform the
dialogue-only model (AUC = 0.6551), suggesting that log-based features provide limited insight into the
content richness of learner input. For lexical variation of training phrases, fusion yielded a slight AUC
increase (0.6089 vs. 0.6016 log-only), but confidence intervals suggest the gain is likely not significant.
Overall, multimodal fusion yields the most substantial gain for predicting training phrase count, slightly
improves the prediction of lexical variation of training phrases, but does not help predict lexical density
of training phrases. Hence, the utility of combining modalities is outcome-dependent.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>6. Discussion</title>
      <sec id="sec-6-1">
        <title>6.1. RQ1: Unimodal Performance</title>
        <p>Our findings reveal the diferential efectiveness of dialogue and log data in predicting project quality on
the process level. The superior performance of log-derived features in predicting training phrase count
aligns with past work on using clickstream data to model learning trajectories [25], indicating behavioral
engagement metrics provide critical insights into productivity and task completion. The stronger
performance of dialogue features in predicting lexical density indicates the spoken discourse appears
to translate into more content-rich chatbot training phrases. This builds on research demonstrating
the value of transcribed speech in detecting self-regulated learning strategies [20] and suggests that
students’ verbal articulation during collaboration may influence the quality of their computational
artifacts [54].</p>
        <p>Overall, log-data-based features were more predictive of engagement, while dialogue-based features
were more indicative of the linguistic characteristics of chatbot training phrases. Future research should
explore how these models learn associations between collaborative actions and outcomes, potentially
incorporating interpretability methods to examine feature importance more precisely [55].</p>
      </sec>
      <sec id="sec-6-2">
        <title>6.2. RQ2: Multimodal Performance</title>
        <p>Multimodal fusion demonstrated mixed results in enhancing predictive accuracy. The improved
prediction of training phrase count through combined features suggests that integrating behavioral and
linguistic cues provides a more comprehensive understanding of student engagement. However, for
the lexical density of training phrases, the combined model underperformed compared to the dialogue
model, suggesting that adding log features may interfere with or dilute the signal from dialogue features
for this task. The cross-modal interaction has also been noted in past work [56], emphasizing that
fusion requires careful consideration of interference. The modest gains in predicting lexical variation
align with past work [25, 31]: the efectiveness of multimodal fusion depends on the prediction task.</p>
        <p>The results reinforce the novelty of our study’s focus on open-ended project-based learning in K-12
AI education, highlighting that predicting linguistic quality in this context presents unique challenges
and opportunities compared to traditional educational data mining tasks. It is evident from our results
3As one attentive reviewer pointed out, counting ’add-training-phrase’ logs might straightforwardly reveal the number of
training phrases. We performed an ablation study, recomputing these accuracies without features dependent on
’add-trainingphrase’, ’delete-phrase’, and ’add-response’. For completeness outcome, AUCs changed to 0.6865 (log only) and 0.6759 in the
combined modalities, respectively.
that straightforward associations between collaborative dialog and process outcomes during learning
are challenging to isolate in our context (as one might conceive that predicted log inputs may be clearly
visible and explicitly mentioned in dialog, and hence straightforward to predict; from our experience,
these cases rarely occur). This contributes to the ongoing discourse on the role of multimodal data for
learning process prediction [26, 19, 20].</p>
      </sec>
      <sec id="sec-6-3">
        <title>6.3. Implications</title>
        <p>The findings highlight the importance of selecting appropriate data modalities for specific outcomes,
contributing to multimodal learning analytics [26, 24]. In K-12, AI learning involving iterative chatbot
design, log data, and dialogue provides complementary insights into productivity and AI understanding.</p>
        <p>For educators assessing collaborative learning, log features ofer insights into engagement and
productivity [25], while dialogue features reveal conceptual understanding and self-regulation [19, 20].
However, our mixed multimodal fusion results suggest that careful feature selection and tuning are
essential to maximize predictive accuracy. These insights inform future research on collaborative AI
literacy tools. With suficient accuracy, our models could monitor engagement and identify when
students need scafolding [ 34, 35]. Dialogue analysis could help educators understand students’ AI
concept mastery, enabling targeted feedback and aligning with growing interest in natural
languageinformed interventions [20, 27, 22]. Future work should evaluate automated transcription feasibility in
real classrooms, balancing efectiveness with privacy considerations and teacher preferences [ 57].</p>
      </sec>
      <sec id="sec-6-4">
        <title>6.4. Limitations and Future Work</title>
        <p>
          First, our data collection was limited to a single middle school science class with a particular collaborative
task, limiting generalizability. Second, our predictive models showed only modest performance in
predicting lexical variation of training phrases, suggesting that the features and modeling techniques
used might not fully capture the complexity of this outcome. These models are not deployment-ready;
their current utility might lie in ofline teacher analytics to inform instruction [ 22]. Future studies
could explore additional features, such as discourse-level linguistic properties or turn-taking dynamics
[
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], other data fusion techniques [58, 59] and feature importance methods (e.g., SHAP) to identify key
collaborative characteristics. Third, our analysis did not separate individual student contributions within
the transcripts, potentially overlooking nuances in student interactions. However, we note that, in the
present study, project-based outcomes are measured and graded as group contributions. Therefore,
such analyses are out of scope for this study and may require finer-grain grading and log data where
interface actions are attributable to specific students, as is common in collaborative learning systems
[19]. Finally, the outcome measurement we selected may not capture certain students’ unexpected
behaviors (e.g., inputting a complex but irrelevant training phrase) [60]. While this case is rare in our
dataset, future work could explore relevance-based outcome measures.
        </p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Conclusion</title>
      <p>This study examines the accuracy of dialogue and log data in predicting process-level collaboration
outcomes in middle school chatbot development. Log features best predict student productivity, while
dialogue-based features are better suited to capturing training phrase richness. Multimodal fusion
improves predictions for training phrase count and, to a lesser extent, lexical variation, highlighting the
outcome-dependent nature of multimodal models. Our research contributes to the field of multimodal
learning analytics by demonstrating the potential and limitations of integrating dialogue and log
data to predict collaborative learning processes and deploying related models in real-time educational
settings. We also contribute insights into the interplay between student interactions and linguistic
outputs in natural language programming tasks. By leveraging both dialogue and log data, educators
and researchers may gain a more holistic understanding of student learning processes, informing the
development of AI-powered collaborative learning tools in K-12 settings.</p>
    </sec>
    <sec id="sec-8">
      <title>Acknowledgments</title>
      <p>This research was supported by the National Science Foundation through grant DRL-2048480. We thank
Christine Fry Wise for her copy-editing of the manuscript.</p>
    </sec>
    <sec id="sec-9">
      <title>Declaration on Generative AI</title>
      <p>During the preparation of this work, the author(s) used ChatGPT, Grammarly in order to: Grammar
and spelling check, Paraphrase and reword. After using this tool/service, the author(s) reviewed and
edited the content as needed and take(s) full responsibility for the publication’s content.
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