Title: How are Researchers Using Data from State Longitudinal Systems?
1How are Researchers Using Data from State
Longitudinal Systems?
- Sean W. Mulvenon, Ph.D.
- Professor of Educational Statistics
- Billingsley Chair for Educational Research and
Policy Studies - University of Arkansas
2Background
- Ph.D. Arizona State (1993)
- Power estimation in repeated measures designs
growth models - Professor of Educational Statistics, University
of Arkansas - Spent 31 months as Senior Advisor
- Office of the Deputy Secretary
- U.S. Department of Education Growth Models
- Internal report on growth models
3We need to use value-added analysis! (Teacher,
2005)
- Why?
- What are value-added analyses?
- What type of data do you have?
- Does everyone agree?
- What are you trying to do?
4Review of Literature using Longitudinal Data
Systems
- Interesting, but problematic in most cases
- Great ideas!
- Problematic due to lack of understanding of the
actual longitudinal data structure - What can you do with the data?
- Incongruence in reporting and models
- Analysis and models correct, but too complicated
for extension to professional development for
teachers - Note 50 of values from studies that are
recomputed are shown to be incorrect in multiple
regression class
5Use of Longitudinal Data Systems for Research
- What are you trying to do?
- Identify research questions and objectives
- Develop appropriate data sets
- Select the appropriate analyses
6Goals of Presentation
- What are Longitudinal Data Systems (LDS)
- Implications for LDS with School Improvement and
Policy associated with NCLB - Evaluate Use of Growth Models with LDS
- Strengths
- Weaknesses
- Limitations
- Challenges
- Expand research capacity to use growth models in
school
7Longitudinal Data Systems
- Issues that must be addressed
- Matching
- Merging
- Functionality of data systems
- Data quality
8Merging Data Sets
- What data are you merging? For what purpose?
- What do you expect to happen?
- Traditionally, data are merged on one variable
- All matches considered successful matches
- Different models
- Probabilistic neural net (probabilities)
- Bashing (Just merge)
- Multiple merging variables
- SQL joins
9Data Merging
- What to expect? (Fantasyland Model)
- A state system has 1,300,000 students K 12 for
two consecutive years and approximately 100,000
students per grade. - Growth Model for Grades 3 8
- A total of six grades in growth model or 600,000
possible students? No! - Grade 3 new in 2nd year
- Grade 8 exited from previous year
- Only 500,000 students expected in growth model!
- Can create confusion in system, i.e., 99.1 match
rate, but only 495,500 students in model from 1.3
million
10Data Merging for Growth Models
- Data Merging should go beyond match rate to
consider horizontal and vertical functionality of
merged data sets! - Horizontally functional data sets
- Vertically functional data sets
- What the .?
11Horizontally Functional Data Sets
- Example Data Set
- School gender sr307 sm307 Diff
- A M 37 51 14
- A M 42 53 11
- A F 41 52 11
- A F 38 54 16
- Note sr307 is Scale Score Reading Grade 3 in
2007 - Average Difference sr307 versus sm307 is 13
points. You can subtract values horizontally in
the system or perform any appropriate
function/operation horizontally to create
variables of interest.
12Vertically Functional Data Sets
- Example Data Set
- School gender sr307 sm307
- A M 37 51
- A M 42 53
- A F 41 52
- A F 38 54
- I can sum the columns to produce average
performance for grade 3 Reading and Math of 39.5
and 52.5, respectively. - You can sum or operate on the columns vertically,
i.e. a vertically functional data set!
13Seem Obvious?
- MYSQL version of same data set
- Student School Grade Gender
Subject Score - 1 A 3 M Reading 37
- 2 A 3 M Reading
42 - 3 A 3 F Reading
41 - 4 A 3 F Reading
38 - 1 A 3 M Math 51
- 2 A 3 M Math 53
- 3 A 3 F Math
52 - 4 A 3 F Math 54
- Even with data management features, not readily
horizontally or vertically functional.
14Assessing Data Quality
- You must cross-validate data with other data
sources - 30,000 3rd and 4th Grade Students Merged
- 2006 100 of students had an assigned FRLP status
- 2007 100 of students had an assigned FRLP status
- Cross-Tabulation revealed 12 of these students
changed their FRLP status - This is simply too volatile for FRLP
- Expected half that volatility
- Typically data quality would be reported as high
- However, clearly there is reporting problem with
this FRLP data
15Implications of Data Quality Example
- Which status do you assign in growth model?
- Students 2006 FRLP status
- Students 2007 FRLP status
- What about the unmatched students?
- What patterns are evident that impacted data
quality?
16Clarity of Research Means
- Sample Data Set
- Subject sr305 sr306 sr307 sr308
- 1 25 31 38
42 - 2 23 32 39
41 - 3 26 33 37
45 - 4 . 34 37
42 - 5 29 36 41
44 - 6 . 33 38
. - 7 . 32 .
45 - 8 28 35 42
44
17Most researchers will run repeated measures
models. The results are predicated on model 2,
not model 1 means
- Model 1 Reported
- Mean1 26.20
- Mean2 33.25
- Mean3 38.86
- Mean4 43.29
- Model 2 Employed
- Mean1 26.20
- Mean2 33.40
- Mean3 39.40
- Mean4 43.20
18Understanding Meaningfulness in Improvement in
Education
Not Meaningful
80
75
Meaningful
75
80
19Data Quality
- It is not just a list of variables
- It is not just matching rates
- Growth Models are much more complicated because
you are involving multiple years of data Most
have difficulty with current year data - It is really a global process of validating,
cross-validating, understanding, and studying
your data sets.
20Growth Modeling is a Field in Statistics
- Difference Scores
- Trend analyses
- Randomized Block Designs
- Covariance models
- Univariate models
- Multivariate models
- Hierarchical Linear Models
- Value-Added Models
- Latent Growth Curve Models
- Structural Equation Models
- Regression/Projection Models
- All potentially appropriate
21NCLB Methods for Growth Models
- Equipercentile Models
- Growth Trajectory Models
2270th Percentile Scale Score 670
Actual Gain 22 Points (PGI 1.1)
Value-Added Gain!
70th Percentile Scale Score 650
Expected Gain 20 Points
Performance Growth Index (PGI)
30th Percentile Scale Score 640
Actual Gain 36 Points (PGI .90
Actual Growth Expected
Growth
PGI
Expected Gain 40 Points
30th Percentile Scale Score 600
22 20
1.1
Year 2
Year 1
23Representing Value-Added Increases in Student
Performance
Actual
Value Added
Predicted
Student B
Actual
Value Added
Predicted
Student A
Red Lines represent predicted student
improvement Blue Lines represent actual student
improvement Value-Added is the increases over
what was predicted for student performance
24Growth Models Research Develop Goals
- Identify student improvement
- District?
- School?
- Classroom?
- Predict Performance
- Student?
- Identify curriculum areas in need of improvement
- Grade?
- Class?
- Professional Development
- Target areas to provide instructional support
Note Classroom is Code for teacher level!
25Growth Models Research Evaluate test data
- Can we actually measure student achievement or
change in student achievement? - Student level
- Linking data accuracy
- Are the tests valid?
- Vertically equated?
- Vertically articulated?
- Multi- versus Uni-Dimensional
- Correlation versus redundancy?
- Issue of content strands
26Growth Models Research Summative Measures
- Accountability
- Secretary Spellings Pilot Growth Model Program
(PGMP) - Prospective versus Retrospective?
- Two Components
- Growth Model
- Scoring Model
- 13 states participating
- Limited impact
- Why?
27Growth Models ResearchFormative Measures
- District/School/Classroom Based
- Standardized or individualized assessments
both? - Tests equated/linked to curriculum?
- Link of state and local assessments?
- Local assessment aligned with state curriculum?
- Prospective versus Retrospective?
- Individual student information for teachers and
parents
28Growth Models Research Methodology
- What is Appropriate?
- Student matching?
- Across all groups
- Change in status (FRLP)
- Covariance models?
- Use of demographics in models
- Imputation procedures?
- Missing data
- Confidence intervals
- How and where to apply?
- What are the decision rules?
- What constitutes adequate growth?
- Use of results?
- Ability of educational stakeholders to understand
the results
29Growth Models Research Outcomes
- Professional development
- Using results in constructive professional
development - Reporting results
- Personnel reports (Private)
- Parent reports (Private)
- School, district or state level reports (Public)
30Example of Research QuestionExpected Scale Score
Growth for Students at the Proficiency Cut Score
-- Arkansas
Grade Progression Gain Gain
Grade Progression Literacy Mathematics
3 to 4 59 points 59 points
4 to 5 45 points 45 points
5 to 6 37 points 37 points
6 to 7 32 points 32 points
7 to 8 27 points 27 points
3 to 8 200 points 200 points
31Arkansas Scale Scores Grades 3 - 8 Non-Linear
and Autoregressive
32Summary Report for School Level Questions
- What percentage of students met the expected
gains for the year for each group? - Did any group differ sizably from the combined
population in meeting growth? - Which group(s)? . What subject(s)?
33(No Transcript)
34(No Transcript)
35Researchers are Summarizing Growth Information
- Evaluating why students did not make expected
progress - Evaluating why students did make expected
progress - Evaluating the differences for these two groups
of students - Identifying if any systematic changes to
instruction, materials, pacing, order of
presentation, etc. impact growth of students - As a whole or for certain sub groups
- Identifying if any individual characteristics or
situations negatively impacted growth - Investigating possible curriculum modifications
that may help specific students achieve as
expected?
36Key Research Questions Being Investigated
Classroom and Student Level
- Which students did not meet expected growth?
- Is there a pattern among the students who did not
meet growth? - Which students did not meet the proficiency
threshold (lost ground this year)? - Is there a pattern?
- What do you know about the students performance
in the subject that may inform further
instructional action or intervention? - What additional information do you need to guide
your instructional decisions? - What resources do you have to gather the
additional information?
37An Example District Growth Model Analysis
- Outcomes
- Professional Development
- Teacher programs and reviews
- Computerized data for teachers and principals
- Student assessments of performance
- Early intervention strategies for students
- Public reporting of school performance
- Making real educational improvements
- Outpacing national trends
38Mean ITBS Literacy Equipercentile Method by
Grade Level
District grade level PGIs indicate students had
greater than expected growth at all grade levels
in Reading, and all grade levels in Language,
except first grade, when compared with national
expected growth.
39Mean ITBS Math Equipercentile Model by Grade
40Teacher Classroom Performance Identifying areas
for professional development
41Analysis
Although one school outperforms the other
according to national percentile ranking, the
lower performing school is making greater gains
with their students. The higher performing school
should look closely at their 7th graders to
determine why they are not making expected growth
across all subject areas
ITBS
PGI
ITBS
PGI
42Closing CommentsImpact of Growth Models
- Represent the best method to comprehensively
evaluate student achievement - Link to curriculum effectiveness
- Link to professional development
- Limited Expertise in Education
- About 50 Ph.D.s annually in this field
- Demonstrated need to expand this field
- Understanding the quality and limitations of your
data set is paramount!
43Closing CommentsGrowth Models Work in Education
- Growth models definitely work in education!!!!
- No such thing as the growth model
- Integrate with specific needs and goals
- Incorporate with professional development
programs - Develop internal capacity/critical mass to help
with your growth models