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Bloom's 2 sigma problem - Wikipedia



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1

Mastery learning

2

Correlations

3

References

4

Further reading

5

External links

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Bloom's 2 sigma problem

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From Wikipedia, the free encyclopedia

Educational phenomenon of greatly improved performance by tutored learners

Bloom's 2 sigma problem
refers to the educational phenomenon that the average student
tutored
one-to-one using
mastery learning
techniques performed two
standard deviations
better than students educated in a
classroom
environment. It was originally observed by
educational psychologist

Benjamin Bloom
and reported in 1984 in the journal
Educational Researcher
.
[
1
]
[
2
]
[
3
]
Bloom's paper analyzed the dissertation results of University of Chicago PhD students Joanne Anania and Joseph Arthur Burke. As quoted by Bloom: "the average tutored student was above 98% of the students in the control class".
[
1
]
:

4

Additionally, the variation of the students' achievement changed: "about 90% of the tutored students ... attained the level of summative achievement reached by only the highest 20%" of the control class.
[
1
]
:

4

The phenomenon's associated problem, as described by Bloom, was to "find methods of group instruction as effective as one-to-one tutoring".
[
1
]
The phenomenon has also been used to illustrate that factors outside of a teachers' control influence student education outcomes, motivating research in alternative
teaching methods
,
[
4
]
in some cases reporting larger standard deviation improvements than those predicted by the phenomenon.
[
5
]
[
6
]
The phenomenon has also motivated developments in
human-computer interaction
for education, including
cognitive tutors
[
6
]
and
learning management systems
.
[
7
]

Mastery learning
[
edit
]

Main article:
Mastery learning

Mastery learning is an
educational philosophy
first proposed by Bloom in 1968
[
8
]
based on the premise that students must achieve a level of mastery (e.g., 90% on a knowledge test) in prerequisite knowledge before moving forward to learn subsequent information on a topic.
[
9
]
Mastery is determined with regular tests, and students who do not yet achieve mastery on the test are given additional educational support before another test. This cycle continues until the learner accomplishes mastery, and they may then move on to the next stage. Failure for a student to achieve mastery is viewed differently from conventional
educational testing
as due to instruction rather than lack of student ability. Another key element of mastery learning is that it requires attention to individual students as opposed to assessing group performance. There is good evidence to suggest the effectiveness of mastery learning for improving student educational outcomes.
[
9
]

Two of the three groups in the original study by Bloom conducted mastery learning, with one
control group
that did not.
[
1
]

Correlations
[
edit
]

Though Bloom concluded that one-to-one tutoring is "too costly for most societies to bear on a large scale", Bloom conjectured that a combination of two or three altered variables may result in a similar performance improvement. Bloom thus challenged researchers and teachers to "find methods of group instruction as effective as one-to-one tutoring".
[
1
]
:

15

Bloom's graduate students Joanne Anania and Arthur J. Burke conducted studies of the effect at different grade levels and in different schools, observing students with "great differences in cognitive achievement, attitudes, and academic self-concept".
[
1
]
:

15

Bloom classified alterable variables that may have, in combination, a 2 sigma effect as the following "objects of change process":

Learner

Instructional material

Home environment or peer group

Teacher

Bloom and his graduate students considered and tested various combinations of these variables, focusing only on those variables that individually had a 0.5 or higher
effect size
. These included:

Effect of selected alterable variables on student achievement
[
1
]
:

6

[
10
]

Object of change process

Alterable variable

Effect size

Percentile equivalent

Teacher

Tutorial instruction

2.00

98

Teacher

Reinforcement

1.2

Learner

Feedback-corrective (
mastery learning
)

1.00

84

Teacher

Cues and explanations

1.00

Teacher, Learner

Student classroom participation

1.00

Learner

Student time on task

1.00

Learner

Improved reading/study skills

1.00

Home environment / peer group

Cooperative learning

0.80

79

Teacher

Homework
(graded)

0.80

Teacher

Classroom morale

0.60

73

Learner

Initial cognitive prerequisites

0.60

Home environment / peer group

Home environment intervention

0.50

69

References
[
edit
]

1

2

3

4

5

6

7

8

Bloom, Benjamin S (June–July 1984).
"The 2 Sigma Problem: The Search for Methods of Group Instruction as Effective as One-to-One Tutoring"

(PDF)
.
Educational Researcher
.
13
(6):
4–
16.
doi
:
10.3102/0013189x013006004
.
S2CID

1714225
. Retrieved
9 June
2018
.

↑

Guskey, Thomas R (2005),
Formative Classroom Assessment and Benjamin S. Bloom: Theory, Research, and Implications
, p.

12,
ERIC

ED490412

↑

Guskey, Thomas R. (2007),
"All Our Children Learning: New Views on the Work of Benjamin S. Bloom"
,
Engaging Every Learner
, Thousand Oaks, CA: Corwin Press, pp.

101–
118,
doi
:
10.4135/9781483329383.n6
,
ISBN

9781412938549
, retrieved
2022-04-27

↑

Wood, William B.; Tanner, Kimberly D. (March 2012).
"The Role of the Lecturer as Tutor: Doing What Effective Tutors Do in a Large Lecture Class"
.
CBE: Life Sciences Education
.
11
(1):
3–
9.
doi
:
10.1187/cbe.11-12-0110
.
ISSN

1931-7913
.
PMC

3292071
.
PMID

22383611
.

↑

Deslauriers, Louis; Schelew, Ellen; Wieman, Carl (2011-05-13).
"Improved Learning in a Large-Enrollment Physics Class"
.
Science
.
332
(6031):
862–
864.
Bibcode
:
2011Sci...332..862D
.
doi
:
10.1126/science.1201783
.
ISSN

0036-8075
.
PMID

21566198
.
S2CID

42770370
.

1

2

Corbett, Albert (2001),
"Cognitive Computer Tutors: Solving the Two-Sigma Problem"
,
User Modeling 2001
, Lecture Notes in Computer Science, vol.

2109, Berlin, Heidelberg: Springer Berlin Heidelberg, pp.

137–
147,
doi
:
10.1007/3-540-44566-8_14
,
ISBN

978-3-540-42325-6
, retrieved
2022-04-27

↑

Mott, Jon; Wiley, David (2013-01-03).
"Open for Learning: The CMS and the Open Learning Network"
.
In Education
.
15
(2).
doi
:
10.37119/ojs2009.v15i2.53
.
ISSN

1927-6117
.

↑

Bloom, Benjamin S. (March 1973).
"Recent developments in mastery learning"
.
Educational Psychologist
.
10
(2):
53–
57.
doi
:
10.1080/00461527309529091
.
ISSN

0046-1520
.

1

2

Winget, Marshall; Persky, Adam M. (2022-01-13).
"A Practical Review of Mastery Learning"
.
American Journal of Pharmaceutical Education
.
86
(10): 8906.
doi
:
10.5688/ajpe8906
.
ISSN

0002-9459
.
PMC

10159400
.
PMID

35027359
.
S2CID

245946166
.

↑

Walberg, Herbert J (May 1984). "Improving the productivity of America's schools".
Educational Leadership
.
41
(8):
19–
27.

Further reading
[
edit
]

Anania, Joanne (1981).
The effects of quality of instruction on the cognitive and affective learning of students
(Thesis). The University of Chicago.

Burke, Arthur Joseph (August 1983).
Students' potential for learning contrasted under tutorial and group approaches to instruction
(Thesis).
OCLC

1194704545
.
ProQuest

252076952
.

External links
[
edit
]

Bloom's 2 Sigma and Vockell's -2 Sigma

Retrieved from "
https://en.wikipedia.org/w/index.php?title=Bloom%27s_2_sigma_problem&oldid=1362032172
"

Categories
:
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Hidden categories:
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.

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Bloom's 2 sigma problem

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Add topic
</reference>

<statements>
1. Intelligent Tutoring Systems (ITS) are "computer-based instructional systems with models of instructional content that specify what to teach, and teaching strategies that specify how to teach." They emerged as a scalable response to Benjamin Bloom's 1984 "2 Sigma Problem," in which one-to-one mastery tutoring produced dramatic gains: Bloom reported that "the average tutored student was above 98% of the students in the control class," and "about 90% of the tutored students…attained the level of summative achievement reached by only the highest 20%" of conventionally taught students—an effect too costly to scale via human tutors.
</statements>

Begin the assessment now. Output only the JSON list, without any conversational text or explanations.