The DOI matches its Crossref record; 25 of the 25 references it cites were found in a registry or an index.
The 2 Sigma Problem: The Search for Methods of Group Instruction as Effective as One-to-One Tutoring
Abstract
T w o University of Chicago doctoral students in education, Anania (1982, 1983) and Burke (1984), completed dissertations in which they compared student learning under the following three conditions of instruction: 1. Conventional. Students learn the subject matter in a class with about 30 students per teacher. Tests are given periodically for marking the students. 2. Mastery Learning. Students learn the subject matter in a class with about 30 students per teacher. The instruction is the same as in the conventional class (usually with the same teacher). Formative tests (the same tests used with the conventional group) are given for feedback followed by corrective procedures and parallel formative tests to determine the extent to which the students have mastered the subject matter. 3. Tutoring. Students learn the subject matter with a good tutor for each student (or for two or three students simultaneously). This tutoring instruction is followed periodically by formative tests, feedback-corrective procedures, and parallel formative tests as in the mastery learning classes. It should be pointed out that the need for corrective work under tutoring is very small.
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Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“skills vary within individuals based on goals, emotional states, and contextual supportsproducing a child's developmental range”
From Malleability, plasticity, and individuality: How children learn and develop in context1 (2019) · cites this paper as Bloom, 1984
In the citing paper
“a child's performance within that range can be optimized under conditions of high, personalized support”
From Malleability, plasticity, and individuality: How children learn and develop in context1 (2019) · cites this paper as Bloom, 1984
In the citing paper
“Bloom found that students who received effective one-on-one tutoring through a mastery learning framework performed two standard deviations better than students who did not.”
From Malleability, plasticity, and individuality: How children learn and develop in context1 (2019) · cites this paper as Bloom, 1984
In the citing paper
“One-to-one tutoring is an effective teaching method (Bloom, 1984).”
From Towards the Pedagogical Steering of Large Language Models for Tutoring: A Case Study with Modeling Productive Failure (2025) · cites this paper as Bloom, 1984
In the citing paper
“We believe that the increased learning from structured AI tutoring is largely due to its ability to offer personalized feedback on demand—just as one-on-one tutoring from a (human) expert is superior to classroom instruction15.”
From AI tutoring outperforms in-class active learning: an RCT introducing a novel research-based design in an authentic educational setting (2025) · cites this paper as [15]
In the citing paper
“While the advantages of personalized instruction are clear, this model of education cannot scale to meet the needs of a large number of students15.”
From AI tutoring outperforms in-class active learning: an RCT introducing a novel research-based design in an authentic educational setting (2025) · cites this paper as [15]
In the citing paper
“Working with an expert personal tutor is generally regarded as the most efficient form of education15.”
From AI tutoring outperforms in-class active learning: an RCT introducing a novel research-based design in an authentic educational setting (2025) · cites this paper as [15]
In the citing paper
“More focused effort on developing computer-based tutoring systems in particular started following the findings of Bloom (Bloom, 1984)—students who received tutoring in addition to group classes fared two standard deviations better than those who only participated in group classes.”
From Proactive and reactive engagement of artificial intelligence methods for education: a review (2023) · cites this paper as Bloom, 1984
Citations
Cites
From dissertation abstracts international
(1974) · ACM SIGGRAPH Computer Graphics · doi:10.1145/988616.988619 · Cited by 12,208
Taxonomy of Educational Objectives. Handbook I: Cognitive Domain
Bloom, B., & Krathwohl, D. R. (1966) · Cited by 4,624
Self-citationThe use of advance organizers in the learning and retention of meaningful verbal material.
Ausubel, D. P. (1960) · Journal of Educational Psychology · doi:10.1037/h0046669 · Cited by 1,457
Educational Outcomes of Tutoring: A Meta-analysis of Findings
Cohen, P. A., Kulik, J. A., & Kulik, C.-L. C. (1982) · American Educational Research Journal · doi:10.3102/00028312019002237 · Cited by 1,138
Taxonomy of Educational Objectives. Handbook I: Cognitive Domain
Blyth, W. A. L., Bloom, B., & Krathwohl, D. R. (1966) · British Journal of Educational Studies · doi:10.2307/3119730 · Cited by 1,123
Self-citationBrophy, J. E., & Good, T. L. (1970) · Journal of Educational Psychology · doi:10.1037/h0029908 · Cited by 922
Slavin, R. E. (1980) · Review of Educational Research · doi:10.3102/00346543050002315 · Cited by 771
Improving the Productivity of America's Schools.
Walberg, H. J. (1984) · Educational leadership · Cited by 731
Jackson, D. R. (2023) · Sage eBooks · doi:10.4135/9781071840801.n92 · Cited by 418
Socio‐psychological Environments and Learning: a quantitative synthesis
Haertel, G. D., Walberg, H. J., & Haertel, E. H. (1981) · British Educational Research Journal · doi:10.1080/0141192810070103 · Cited by 354
Research works printed but not linked: 13
- Anania J, 1982, Dissertation Abstracts International, 42, 4269A
- Bloom BS, 1980, Phi Delta Kappan, 61, 6
- Burke AJ, 1984, Dissertation Abstracts International, 44, 2025A
- DaveRHThe identification and measurement of environment process variables that are related to educational achievement1963(Unpublished doctoral dissertation, University of Chicago)
- DolanLJThe affective correlates of home concern and support, instructional quality, and achievement1980(Unpublished doctoral dissertation, University of Chicago)
- JanhomSEducating parents to educate their children1983(Unpublished doctoral dissertation, University of Chicago)
- Leyton FS, 1983, Dissertation Abstracts International, 44, 974A
- MevarechZRThe role of teaching-learning strategies and feed-back-corrective procedures in developing higher cognitive achievement1980(Unpublished doctoral dissertation, University of Chicago)
- NordinABThe effects of different qualities of instruction on selected cognitive, affective, and time variables1979(Unpublished doctoral dissertation, University of Chicago)
- Nordin AB, 1980, Evaluation: in Education: An International Review Series, 4, 2
- Tenenbaum G, 1982, Dissertation Abstracts International, 43, 1822A
- WolfRMThe identification and measurement of home environmental process variables that are related to intelligence1964(Unpublished doctoral dissertation, University of Chicago)
- Wolf RM, 1966, Testing Problems in Perspective
Cited by
Sorted by citations
The role of deliberate practice in the acquisition of expert performance
Ericsson, K. A., Krampe, R. T., & Tesch-Römer, C. (1993) · Psychological Review · doi:10.1037/0033-295x.100.3.363 · Cited by 9,564
“Research in education reviewed by Bloom (1984) shows that when students are randomly assigned to instruction by a tutor or to conventional teaching, tutoring yields better performance by two standard deviations—the average tutored student performed at the 98th percentile of students taught with the…”
BackgroundHake, R. R. (1998) · American Journal of Physics · doi:10.1119/1.18809 · Cited by 6,072
Anderson, J. R., Boyle, C., & Reiser, B. (1985) · Science · doi:10.1126/science.228.4698.456 · Cited by 699
VanLEHN, K. (2011) · Educational Psychologist · doi:10.1080/00461520.2011.611369 · Cited by 2,323
“A common belief among computer tutoring researchers is that human tutoring has an effect size of d = 2.0 relative to classroom teaching without tutoring (Bloom, 1984; Corbett, 2001; Evens & Michael, 2006; Graesser et al., 2001; VanLehn et al., 2007; Woolf, 2009).”
BackgroundMethodInfluentialSocial robots for education: a review.
Belpaeme, T., Kennedy, J., Ramachandran, A., Scassellati, B., & Tanaka, F. (2018) · Science Robotics · doi:10.1126/scirobotics.aat5954 · Cited by 1,558
Metadata
- Authors
- BLOOM, B. S.
- Affiliations
- Northwestern University (US)
- Corresponding author
- BLOOM, BENJAMIN S.
- Venue
- Educational Researcher
- Published
- 1984-06
- Volume
- 13
- Issue
- 6
- Pages
- 4-16
- ISSN
- 0013-189X (ISSN-L)
- 1935-102X
- OpenAlex
- W2172010324
- Cited by
- 2,734
- References
- 25
- Citations by year
- 2026: 195 · 2025: 144 · 2024: 131 · 2023: 99 · 2022: 103 · 2021: 84 · 2020: 129 · 2019: 88 · 2018: 122 · 2017: 79 · 2016: 97 · 2015: 119 · 2014: 112 · 2013: 107 · 2012: 103
- FWCI
- 39.22
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Educational Researcher (publishedVersion)
- Topics
- Social Sciences › Psychology › Developmental and Educational Psychology › Innovative Teaching and Learning Methods
- Physical Sciences › Computer Science › Artificial Intelligence › Intelligent Tutoring Systems and Adaptive Learning
- Social Sciences › Psychology › Developmental and Educational Psychology › Learning Styles and Cognitive Differences
- Keywords
- group instruction, one-on-one tutoring, learning mastery, conventional instruction, corrective procedures, academic performance, tutoring effectiveness
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- BLOOM, B. S. (1984). The 2 Sigma Problem: The Search for Methods of Group Instruction as Effective as One-to-One Tutoring. Educational Researcher. https://doi.org/10.3102/0013189x013006004
