Threats To Validity In A Study Of The Effects Of Hypermedia Instruction On Learning Outcomes A Switched Replications Experiment
Bibliographic record
Abstract
Educational researchers in university settings face many difficulties in trying to conduct controlled action research studies on the effects of hypermedia on learning outcomes, where threats to validity and reliability are often beyond the influence of the investigator.Switched Replications experiment and another, semester-long study, where all students received hypermedia instruction in which it was embedded, were specifically conducted to address several validity threats.In each of the two weeks of the experiment, one group of students received a hypermedia lecture, while the other group received a conventional lecture on the same topic.The two lectures were immediately followed by a test.Two instructors were involved.The hypermedia-instructed group performed significantly better both times, regardless of which instructor made presentations.However, there were no statistically significant differences in overall academic achievement of the students in the course, offered in a hypermedia mode for 12 out of its 13 weeks.This indicated that the choice of instructional media had a strong effect on student achievement, while the effect of instructor differences was negligible.Selection bias, novelty factor, differences in instructional design and social threats to the internal validity of the study were also rejected as a possible explanation for the observed differences in achievement.I.
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How this classification was reachedexpand
Direct model labels (unvalidated)
Per-model category and study-design labels from the labeling rounds. They are machine output, unvalidated, and the disagreement between models ships as data. No study design here is MEDLINE-validated yet.
| Model arm | Categories | Study design | Confidence |
|---|---|---|---|
| gemma | Metaresearch Domain: Methods · Genre: Empirical About the Canadian research system: no · About a Canadian topic: no | Observational | low |
| gpt | no category Domain: not available · Genre: Empirical About the Canadian research system: no · About a Canadian topic: no | Other design | low |
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.563 | 0.735 |
| Meta-epidemiology (narrow) | 0.003 | 0.002 |
| Meta-epidemiology (broad) | 0.003 | 0.005 |
| Bibliometrics | 0.004 | 0.004 |
| Science and technology studies | 0.005 | 0.017 |
| Scholarly communication | 0.005 | 0.006 |
| Open science | 0.006 | 0.007 |
| Research integrity | 0.008 | 0.007 |
| Insufficient payload (model declined to judge) | 0.005 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedLabeled directly by 2 models reading the full record.
The models disagree on parts of this classification; every voice is preserved in the section at the end of the page.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".