The Persistence of the Gender Gap in Introductory Physics

Lauren Kost

Steven Pollock, Noah Finkelstein

Department of Physics,

University of Colorado at Boulder

July 21, 2008

Acknowledgments• Physics faculty:

Michael DubsonNoah FinkelsteinKathy PerkinsSteven PollockCarl Wieman

• Ph. D. students:Charles BailyLauren KostBenjamin SpikeChandra Turpen

• Postdocs:Stephanie ChasteenSteven GoldhaberLaurel MayhewSam McKaganArchie PaulsonNoah Podolefsky

• School of Ed members:Valerie OteroKara GrayBud Talbott III

This material is based upon work supported by the National Science Foundation under Grant No. REC 0448176, CAREER: Physics Education and Contexts of Student Learning. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the NSF

MotivationAIP Statistics:

50% of physics students in HS are female22% of bachelors in physics go to females10% of faculty in physics are female

Lorenzo et. al. Am. J. Phys. 74, 118 (2006)

Harvard Claim:Fully interactive courses eliminate the gender gap.

Interactive Engagement techniques better than Traditional Lecture

Hake, Am. J. Phys. 66, 64 (1998)

Gender Gaps at CU Boulder

0

2

4

6

8

10

12

14

16

18

20

Partial Partial Partial

Level of Engagement

FM

CE

<S

>M

- <

S>

F (

%)

Pretest Posttest

Gender Gaps at CU Boulder

0

2

4

6

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14

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18

20

Partial Partial Partial Full Full Full Full

Level of Engagement

FM

CE

<S

>M

- <

S>

F (

%)

Pretest Posttest

Gender Gaps at CU Boulder

0

2

4

6

8

10

12

14

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Partial Partial Partial Full Full Full Full All

Level of Engagement

FM

CE

<S

>M

- <

S>

F (

%)

Pretest Posttest

Conclusions (I)

• Despite fully interactive techniques, gender gap persists at our institution

• Harvard claims results independent of instructor, we see otherwise

• Where does the gender gap come from? Why does it exist?– Do gender differences exist in other

aspects of the introductory course?

Gender Gaps in Course Grades

-10 -5 0 5 10

Course Grade

Exams

Participation

Homework

<S>M - <S>F (%)

Females higher Males higher

Gender Gaps in CLASS Shifts

Gender Gaps in BackgroundEffect Size

HS GPA * 0.47

SAT – Math * 0.33

ACT – Math * 0.14

Females Males1 year HS Physics * 80% 89%

1 year HS Calculus 70% 67%

* = statistically significant difference

0

10

20

30

40

50

60

70

80

90

100

0 <= S <= 12 12 < S <= 18 18 < S <= 27 27 < S <= 45 45 < S <= 100

FMCE Pretest score (%)

Av

g. F

MC

E P

os

tte

st

sc

ore

(%

)

Females Males

Impact of Pretest on Post Test

rpre,post = 0.56

37% 19%

8% 22%

21% 16%

14% 22%20% 21%

Regression Analyses

• Control for prior physics and math knowledge and incoming attitudes and beliefs

• Multiple Regression– The average posttest gender difference is 3%

(reduced from the observed difference of 10%).

– 70% of the gender gap is accounted for by background differences.

Conclusions• Gender differences exist in several aspects

• Males and females are differently prepared

• Differences in male and female backgrounds account for about 70% of the gender gap

Thank You

• Find more info at:

http://per.colorado.edu

• Pollock, et al, PRST PER 3, 010107 (2007)

• Kost, et al, PERC Proceedings 2007, p. 137

• PRST PER paper in review

• Poster at PST4 from 5 – 6 PM on Tuesday

Courses, Student Population, and Data• 7 semesters introductory, calculus-based mechanics

– 3 semesters Partially Interactive (without Tutorials)– 4 semesters Fully Interactive (with Tutorials)

• Student population– 25% female– 50% engineering majors (6% physics majors)– 80% white

• Data sources– Matched FMCE pre/post data (N ~ 2100)– Matched CLASS pre/post data (N ~ 1900)– Course grades (N ~ 3600)– Demographic and background data (N ~ 3600)

Gender Gaps at CU Boulder

Pollock, et. al. Phys. Rev. ST PER, 3, 010107 (2007)

0

2

4

6

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12

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18

Partially Interactive Fully Interactive

<S

>M

- <

S>

F (

%)

Pretest Posttest

Multiple Regression

• What is the difference between a male’s and a female’s scores, after controlling for several important factors?

• Sample of 1027 students (30% of population)

Building the Model

Dependent Variable: FMCE Posttest

Independent Variables: Gender

FMCE Pretest

Math Score

CLASS Pre Overall Fav

Other Independent Variables:

HS GPA

HS Physics

HS Calculus

Ethnicity

Regression Model

PREFEMALEb

CLASSb

MATHbPREb

FEMALEbbPOST

5

4

32

10

Interaction: gender & pretest

Females

Males

Regression Model

PREFEMALEb

CLASSb

MATHbPREb

FEMALEbbPOST

5

4

32

10

Gender Effect

PREbb 51EffectGender

CLASSbMATHb

PREbbPOST

43

20 :M

CLASSbMATHb

PREbbbbPOST

43

5210 )( :F

Regression ResultsModel Summary

.650 .423 .420 21.10490Model1

R R SquareAdjustedR Square

Std. Error ofthe Estimate

ANOVA

333098.7 5 66619.747 149.567 .000

454770.7 1021 445.417

787869.5 1026

Regression

Residual

Total

Model1

Sum ofSquares df Mean Square F Sig.

Coefficients

31.459 2.954 10.650 .000

-9.978 2.618 -.163 -3.811 .000

.585 .040 .426 14.663 .000

.225 .085 .112 2.659 .008

.242 .043 .140 5.617 .000

7.241 .871 .216 8.311 .000

(Constant)

GENDER2

FMCEPRE

GEND_FMCEPRE2

@1110_PRE_OV_FAV

MATHCOMBINED

Model1

B Std. Error

UnstandardizedCoefficients

Beta

StandardizedCoefficients

t Sig.

Regression Results

PREFEMALE

CLASSMATH

PREFEMALEPOST

2.0

2.07

6.01031

PRE 2.010EffectGender

Gender Effect

-10

-8

-6

-4

-2

0

2

4

6

8

10

0 10 20 30 40 50 60 70

FMCE Pretest (%)

Ge

nd

er

Eff

ec

t (M

-F)

Conclusions

• Even when controlling for physics background, math skills, and attitudes and beliefs, gender is still a significant factor in posttest score.

• Accounted for only 43% of variation in post test scores, other factors to consider

Normalized Gain

0

0.1

0.2

0.3

0.4

0.5

0.6

IE 1 IE 2

Avg

. N

orm

aliz

ed G

ain

Females Males

Normalized Gain by semester

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

SP 04 Tut

FA 04 Grps

SP 05 Trad

FA 05 Trad

SP 06 Tut

FA 06 Tut

SP 07 Tut

ALL

Av

g.

No

rma

lize

d G

ain

Females Males

Multiple Regression

Gender Gaps in Physics 2

0

5

10

15

20

25

Fall 04 Spring 05 Fall 05 Spring 06 Fall 06 Spring 07 All

<S

>M

- <

S>

F

0

5

10

15

20

25

30FMCE Posttest BEMA Pretest BEMA PosttestN

/A

Gender Gaps in Physics 2

0

5

10

15

20

25

Fall 04 Spring 05 Fall 05 Spring 06 Fall 06 Spring 07 All

<S

>M

- <

S>

F

0

5

10

15

20

25

30FMCE Posttest BEMA Pretest BEMA PosttestN

/A

Matched Analysis – 1110 Gain

rpre,gain = 0.281

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0 <= S <= 12 12 < S <= 18 18 < S <= 27 27 < S <= 45 45 < S <= 100

Females Males