Martial Arts Benefits Analysis

8/3/2019 Martial Arts Benefits Analysis

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Studies With Covariates

ANOVA vs. ANCOVA

andMANOVA vs. MANCOVA


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OverviewOverview To look at using covariates in analysis,

we will look at real data from twostudies.

Study of Childs Self-Concept after MartialArts Training. (Single Dependent Variable)

Study of Neurological treatment on ADHDkids. (Multiple Dependent Variables)

To look at using covariates in analysis,we will look at real data from twostudies.

Study of Childs Self-Concept after MartialArts Training. (Single Dependent Variable)

Study of Neurological treatment on ADHDkids. (Multiple Dependent Variables)


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Hypothesis: That students in a collegestatistics class will retain more fromclassroom presentations if they arebribed.

Approximately 20 students will be given

chocolate in a college statistics class. Results pending

Hypothesis: That students in a collegestatistics class will retain more fromclassroom presentations if they arebribed.

Approximately 20 students will be given

chocolate in a college statistics class. Results pending

Bonus Study!Bonus Study!


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Children in Martial Arts

Study Characteristics


Study Characteristics Hypothesis: That children will gain positive

self-concept after an 8 week martial arts

program for kids. Children 7 to 12 years of age with no

previous martial arts experience wererandomly assigned to either a treatment

group that attended martial arts classes for aperiod of 8 weeks, or to a control group thatreceived no martial arts training.

Hypothesis: That children will gain positiveself-concept after an 8 week martial arts

program for kids. Children 7 to 12 years of age with no

previous martial arts experience wererandomly assigned to either a treatment

group that attended martial arts classes for aperiod of 8 weeks, or to a control group thatreceived no martial arts training.


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Study Characteristics Participants were selected from schools in

the north Scottsdale, Arizona area.

The instrument used to measure self-concept and body image was the Piers-Harris Childrens Self-Concept Scale. This

is an 80 question test that is easy to take,administer, and score.

A Pre and Post test was given.

Participants were selected from schools inthe north Scottsdale, Arizona area.

The instrument used to measure self-concept and body image was the Piers-Harris Childrens Self-Concept Scale. This

is an 80 question test that is easy to take,administer, and score.

A Pre and Post test was given.


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Study Characteristics Data Data

Group 1

No MartialArts Training

Group 2

Martial ArtsTrained


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Children in Martial Arts -

Analysis


Analysis First: analysis on the Post test using the

Pre test as a covariate (ANCOVA).

Then: analysis by taking a differencescore between the Pre and Post test forthe treatment and control groups

(ANOVA).

First: analysis on the Post test using thePre test as a covariate (ANCOVA).

Then: analysis by taking a differencescore between the Pre and Post test forthe treatment and control groups

(ANOVA).


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ANCOVA


ANCOVA The Pretest scores are not significantly

different between groups The Pretest scores are not significantly

different between groups

EstimatesDependent Variable: PRETEST

Mean Std. Error 95% Confidence IntervalGROUP Lower Bound Upper Bound

165

.500 2

.323 60

.706

70.

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4

2 69.714 2.150 65.276 74.153

Descriptive StatisticsDependent Variable: PRETESTGROUP Mean Std. Deviation N1 65.5000 6.73525 122 69.7143 9.00793 14

Total 67.7692 8.16974 26


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ANCOVA


ANCOVA The following pages are the ANCOVA

Results The following pages are the ANCOVA

Results


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ANCOVA


ANCOVA The results didnt reject the null

hypothesis (p=.073 level) despite the

differences in the means.

Looking at the graph of Pretest vs. Postwill reveal the ceiling effect.

The results didnt reject the nullhypothesis (p=.073 level) despite the

differences in the means.

Looking at the graph of Pretest vs. Postwill reveal the ceiling effect.


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ANCOVA


ANCOVAAs the scores

approach the

maximum(80), thedifferences

between thescores areminimized.

As the scoresapproach the

maximum(80), thedifferences

between thescores areminimized.

Pretest Mean


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EstimatesDependent Variable: POSTTEST

Mean Std. Error 95% Confidence Interval

GROUP Lower Bound UpperBound1 59.310 2.131 54.891 63.7292 65.424 2.253 60.752 70.095a Evaluated at covariates appeared in the model: PRETEST= 60.00.


Mean Std. Error 95% Confidence Interval

GROUP Lower Bound UpperBound1 59.310 2.131 54.891 63.7292 65.424 2.253 60.752 70.095a Evaluated at covariates appeared in the model: PRETEST= 60.00.

Pairwise ComparisonsDependent Variable: POSTTEST

Mean Difference (I-J) Std. Error Sig. 95%Confidence Interval for Difference(I) GROUP (J) GROUP Lower Bound UpperBound1 2 -6.114 3.101 .061 -12.544 .3172 1 6.114 3.101 .061 -.317 12.544Based on estimated marginal meansa Adjustment for multiple comparisons: Least Significant Difference (equivalent to noadjustments).


Mean Difference (I-J) Std. Error Sig. 95%Confidence Interval for Difference(I) GROUP (J) GROUP Lower Bound UpperBound1 2 -6.114 3.101 .061 -12.544 .3172 1 6.114 3.101 .061 -.317 12.544Based on estimated marginal meansa Adjustment for multiple comparisons: Least Significant Difference (equivalent to noadjustments).


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Mean Std. Error 95% Confidence IntervalGROUP Lower Bound Upper Bound1 49.570 4.220 40.818 58.3232 58.360 3.725 50.635 66.084a Evaluated at covariates appeared in the model: PRETEST = 50.00.




Mean Difference (I-J) Std. Error Sig. 95% ConfidenceInterval for Difference(I) GROUP (J) GROUP Lower Bound Upper Bound1 2 -8.789 5.629 .133 -20.463 2.8842 1 8.789 5.629 .133 -2.884 20.463Based on estimated marginal meansa Adjustment for multiple comparisons: Least Significant Difference (equivalent to no adjustments).


Mean Difference (I-J) Std. Error Sig. 95% ConfidenceInterval for Difference(I) GROUP (J) GROUP Lower Bound Upper Bound1 2 -8.789 5.629 .133 -20.463 2.8842 1 8.789 5.629 .133 -2.884 20.463Based on estimated marginal meansa Adjustment for multiple comparisons: Least Significant Difference (equivalent to no adjustments).


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Mean Difference (I-J) Std. Error Sig. 95% ConfidenceInterval for Difference(I) GROUP (J) GROUP Lower Bound Upper Bound1 2 -5.311 2.574 .051 -10.648 2.640E-022

15.311

2.57

4.

051 -

2.640

E-02

10.64

8Based on estimated marginal meansa Adjustment for multiple comparisons: Least Significant Difference (equivalent to no adjustments).


Mean Difference (I-J) Std. Error Sig. 95% ConfidenceInterval for Difference(I) GROUP (J) GROUP Lower Bound Upper Bound1 2 -5.311 2.574 .051 -10.648 2.640E-022

15.311

2.57

4.

051 -

2.640

E-02

10.64

8Based on estimated marginal meansa Adjustment for multiple comparisons: Least Significant Difference (equivalent to no adjustments).






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ANOVA/Difference Scores


ANOVA/Difference Scores Now to repeat the analysis with

difference scores. Now to repeat the analysis with

difference scores.


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ANOVA/Difference Scores The

difference

scores

Thedifference

scores

Mean2=2.571

Mean1=-0.833


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ANOVA/Difference Scores This Graph

also

illustratesCeilingEffect atmaximumPre scores.

No where togo butDOWN

This Graphalso

illustratesCeilingEffect atmaximumPre scores.

No where togo butDOWN


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ANCOVA vs. ANOVAANCOVA vs. ANOVA The ANCOVA results were more

significant because there was more

variance in the scores in the Post testcompared to the difference scores inthe ANOVA.

Theceiling effect resulted indifficulty measuring the effects.

The ANCOVA results were moresignificant because there was more

variance in the scores in the Post testcompared to the difference scores inthe ANOVA.

Theceiling effect resulted indifficulty measuring the effects.


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MANCOVA vs. MANOVAMANCOVA vs. MANOVA Now we look at a different data set with

multiple independent variables Now we look at a different data set with

multiple independent variables


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MANCOVA vs. MANOVA


MANCOVA vs. MANOVA

Study Characteristics 2 groups-neurological and control

30 children

age 6-15 per group 4 time measures:

Immediate

Delayed

Retrospective Reproduction

Scores on items turned into ratio scores

2 groups-neurological and control

30 children

age 6-15 per group 4 time measures:

Immediate

Delayed

Retrospective Reproduction

Scores on items turned into ratio scores


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MANCOVA vs. MANOVA


MANCOVA vs. MANOVA

Study Characteristics ADHD Rating Scales

Parent Total Score

Teacher Total Score MANOVA performed to investigate

whether population means on the timemeasures vary across group

ADHD Rating Scales Parent Total Score

Teacher Total Score MANOVA performed to investigate

whether population means on the timemeasures vary across group


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MANOVA ResultsMANOVA Results- - - P A R T I A L C O R R E L A T I O N C O E F F I C I E N T S- - -

Controlling for.. AGE

CODING SYMBOL BIRTHDAY TOTALFLA ADHDPT

CODING 1.0000 .4862 .2568 .2290 -.0420

( 0) ( 57) ( 57) ( 57) ( 57)P= . P= .000 P= .050 P= .081 P= .752

SYMBOL .4862 1.0000 .2694 .3525 -.1352

( 57) ( 0) ( 57) ( 57) ( 57)

P= .000 P= . P= .039 P= .006 P= .307

BIRTHDAY .2568 .2694 1.0000 .3815 -.2591

( 57) ( 57) ( 0) ( 57) ( 57)

P= .050 P= .039 P= . P= .003 P= .048

TOTALFLA .2290 .3525 .3815 1.0000 -.4745

( 57) ( 57) ( 57) ( 0) ( 57)

P= .081 P= .006 P= .003 P= . P= .000

ADHDPT -.0420 -.1352 -.2591 -.4745 1.0000

( 57) ( 57) ( 57) ( 57) ( 0)

P= .752 P= .307 P= .048 P= .000 P= .

(Coefficient / (D.F.) / 2-tailed Significance)


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Covariate Studies - SummaryCovariate Studies - SummaryANOVA vs. ANCOVA Case (Martial Arts)

In this case we see that ANCOVA is

preferable to ANOVA on difference scoresand it illustrates the ceiling effect

MANOVA vs. MANCOVA Case

Martial Arts Master and KarateInstructor

Cave Creek, Chandler, Mesa,

Scottsdale

ANOVA vs. ANCOVA Case (Martial Arts)

In this case we see that ANCOVA is

preferable to ANOVA on difference scoresand it illustrates the ceiling effect

MANOVA vs. MANCOVA Case

Martial Arts Master and KarateInstructor

Cave Creek, Chandler, Mesa,

Scottsdale

Documents

Martial Arts Benefits Analysis