educational statistics: avoiding population and sampling pitfalls meredith wachs

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Educational Educational Statistics: Statistics: Avoiding Avoiding Population and Population and Sampling Pitfalls Sampling Pitfalls Meredith Wachs Meredith Wachs

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Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs. Demographics of Johnson County, Tennessee. 2008 Census Bureau Estimates: Population: 18,112 (3.5% growth from 2000) Ethnicities: 96% White, 3% Black, 1% Hispanic - PowerPoint PPT Presentation

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Page 1: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Educational Statistics: Educational Statistics: Avoiding Population Avoiding Population and Sampling Pitfallsand Sampling Pitfalls

Meredith WachsMeredith Wachs

Page 2: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Demographics of Johnson County, Demographics of Johnson County, TennesseeTennessee

2008 Census Bureau Estimates:2008 Census Bureau Estimates: Population: 18,112 (3.5% growth from 2000)Population: 18,112 (3.5% growth from 2000) Ethnicities: 96% White, 3% Black, 1% Ethnicities: 96% White, 3% Black, 1%

HispanicHispanic High school graduates, age 25+: 58.4% (as of High school graduates, age 25+: 58.4% (as of

2000, compared with 75.9% statewide)2000, compared with 75.9% statewide) Bachelor’s degree or higher, age 25+: 6.9% (as Bachelor’s degree or higher, age 25+: 6.9% (as

of 2000, compared with 19.6% statewide)of 2000, compared with 19.6% statewide) Mean travel time to work: 32 minutes (as of Mean travel time to work: 32 minutes (as of

2000)2000)

Page 3: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

More DemographicsMore Demographics Median Household Income (as of 2007): Median Household Income (as of 2007):

$30,447 (compared with $42,389 statewide)$30,447 (compared with $42,389 statewide) Below poverty line: 21.9% (as of 2007, 15.8% Below poverty line: 21.9% (as of 2007, 15.8%

statewide)statewide) All these stats can be found at All these stats can be found at

http://quickfacts.census.gov/qfd/states/47/4709http://quickfacts.census.gov/qfd/states/47/47091.html1.html

Mountain City, the county seat, had 2,383 Mountain City, the county seat, had 2,383 residents as of 2000 (residents as of 2000 (http://http://en.wikipedia.org/wiki/Mountain_City,_Tennesen.wikipedia.org/wiki/Mountain_City,_Tennesseesee). ).

Page 4: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Demographics continued…Demographics continued…

Johnson County also has had a maximum security Johnson County also has had a maximum security prison, Northeast Correctional Complex, which prison, Northeast Correctional Complex, which houses 1,819 inmates, since 1991 (houses 1,819 inmates, since 1991 (http://www.tennessee.gov/correction/institutions/necxhttp://www.tennessee.gov/correction/institutions/necx.html.html). ).

Unemployment as of February 2009: 11.8%; 9.5% Unemployment as of February 2009: 11.8%; 9.5% statewidestatewide

As of per capita income of $19,680, Johnson County As of per capita income of $19,680, Johnson County is the 4is the 4thth poorest county in Tennessee ( poorest county in Tennessee (http://www.tennessee.gov/tacir/County_Profile/johnshttp://www.tennessee.gov/tacir/County_Profile/johnson_profile.htmon_profile.htm). ).

Page 5: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Johnson County School SystemJohnson County School System Johnson County Schools include five elementary Johnson County Schools include five elementary

schools (pre-K-6), one middle school (grades 7-8), schools (pre-K-6), one middle school (grades 7-8), and one high school, along with an Extended Services and one high school, along with an Extended Services Center, Headstart, and Adult Education programs.Center, Headstart, and Adult Education programs.

They served 2,426 students in the 2005-2006 school They served 2,426 students in the 2005-2006 school year, with a 15:1 student-teacher ratio (NCES, year, with a 15:1 student-teacher ratio (NCES, http://www.education.com/schoolfinder/us/tennessee/http://www.education.com/schoolfinder/us/tennessee/district/johnson-county-school-district/district/johnson-county-school-district/).).

Dropout Rate: 14.6% in 2007-2008 school year Dropout Rate: 14.6% in 2007-2008 school year (10.1% statewide; (10.1% statewide; http://www.tennessee.gov/tacir/County_Profile/johnshttp://www.tennessee.gov/tacir/County_Profile/johnson_profile.htmon_profile.htm). ).

Page 6: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

JC Schools continued…JC Schools continued…

In the 2005-2006 school year, Johnson County had In the 2005-2006 school year, Johnson County had 73.1% of students qualify for free or reduced lunch 73.1% of students qualify for free or reduced lunch (rank 143 out of 155 systems in TN; state average: (rank 143 out of 155 systems in TN; state average: 52.9%).52.9%).

18.3% of students had disabilities (state average, 18.3% of students had disabilities (state average, 15.9%).15.9%).

$7,973 were spent per student (rank 21; state average: $7,973 were spent per student (rank 21; state average: $7,469)$7,469)

Tennessee ranks 45Tennessee ranks 45thth in spending. in spending. All data from Tennessee Education Association:All data from Tennessee Education Association:http://www.teateachers.org/cms/Per+Pupil+Expenditurehttp://www.teateachers.org/cms/Per+Pupil+Expenditures/103.htmls/103.html

Page 7: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs
Page 8: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

No Child Left BehindNo Child Left Behind Nationwide, schools must test every year from 3Nationwide, schools must test every year from 3rdrd-8-8thth grade, grade,

and at least once in 10and at least once in 10thth-12-12thth. . Originally just reading, writing, and math, schools must now Originally just reading, writing, and math, schools must now

assess science, too.assess science, too. Highly qualified teachers must teach core subjects.Highly qualified teachers must teach core subjects. 95% of students must be present for testing, or three-year 95% of students must be present for testing, or three-year

average must be 95%.average must be 95%. AYP (Adequate Yearly Progress) must be made in the state AYP (Adequate Yearly Progress) must be made in the state

testing, along with graduation rate for secondary and (usually) testing, along with graduation rate for secondary and (usually) attendance rate for elementary schools, for the whole school attendance rate for elementary schools, for the whole school and each disability, economic, and racial subgroup.and each disability, economic, and racial subgroup.

http://www.stateline.org/live/ViewPage.action?siteNodeId=13http://www.stateline.org/live/ViewPage.action?siteNodeId=136&languageId=1&contentId=416116&languageId=1&contentId=41611

http://www2.edtrust.org/NR/rdonlyres/37B8652D-84F4-http://www2.edtrust.org/NR/rdonlyres/37B8652D-84F4-4FA1-AA8D-319EAD5A6D89/0/ABCAYP.PDF 4FA1-AA8D-319EAD5A6D89/0/ABCAYP.PDF

Page 9: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

NCLB continuedNCLB continued ““No Child Left Behind, President Bush’s signature education No Child Left Behind, President Bush’s signature education

reform law signed in 2002, is designed to raise academic reform law signed in 2002, is designed to raise academic achievement for all students and close gaps that separate achievement for all students and close gaps that separate students of color and low-income students from their peers by students of color and low-income students from their peers by the 2013-2014 school year. All public schools and districts are the 2013-2014 school year. All public schools and districts are subject to NCLB goals and reporting requirements. Schools or subject to NCLB goals and reporting requirements. Schools or districts receiving Title I federal funds, which are earmarked districts receiving Title I federal funds, which are earmarked for needy students and go to about 90 percent of public school for needy students and go to about 90 percent of public school districts in the U.S., are subject to penalties designed to close districts in the U.S., are subject to penalties designed to close achievement gaps.” (Peterson, achievement gaps.” (Peterson, http://http://www.stateline.org/live/ViewPage.action?siteNodeIdwww.stateline.org/live/ViewPage.action?siteNodeId=136&languageId=1&contentId=41611=136&languageId=1&contentId=41611). ).

Page 10: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

NCLB continued…NCLB continued… “To account for those students with serious cognitive

disabilities for whom grade-level standards are not appropriate, school districts and states can exempt up to 1% of all students… from grade-level testing.” from grade-level testing.”

““Safe Harbor” provision: If a school system cuts the percent of Safe Harbor” provision: If a school system cuts the percent of non-proficient students by 10%, they are not penalized for not non-proficient students by 10%, they are not penalized for not making AYP.making AYP.

Schools are then assigned a “grade” for each subject and grade Schools are then assigned a “grade” for each subject and grade level; to earn an “A”, students may have to gain more than 1.5 level; to earn an “A”, students may have to gain more than 1.5 school years in one year.school years in one year.

The overall goal is for 100% of students to be proficient in the The overall goal is for 100% of students to be proficient in the tested subjects by 2014.tested subjects by 2014.

http://www2.edtrust.org/NR/rdonlyres/37B8652D-84F4-http://www2.edtrust.org/NR/rdonlyres/37B8652D-84F4-4FA1-AA8D-319EAD5A6D89/0/ABCAYP.PDF 4FA1-AA8D-319EAD5A6D89/0/ABCAYP.PDF

Page 11: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

What Happens When AYP Isn’t Reached?What Happens When AYP Isn’t Reached? Penalty timeline for schools "in need of improvement":Penalty timeline for schools "in need of improvement":

   After 2 yearsAfter 2 years: Schools must allow parents to transfer their children to : Schools must allow parents to transfer their children to

other public schools. They also must develop a school improvement plan other public schools. They also must develop a school improvement plan and spend 10 percent of their Title I allocation on teacher professional and spend 10 percent of their Title I allocation on teacher professional development.development.

After 3 yearsAfter 3 years: Schools must provide eligible students with "supplemental : Schools must provide eligible students with "supplemental services," which generally means tutoring. services," which generally means tutoring. 

After 4 yearsAfter 4 years: Schools must take "corrective action," such as replacing : Schools must take "corrective action," such as replacing school staff, adopting new curriculum or extending the school day.school staff, adopting new curriculum or extending the school day.

After 5 yearsAfter 5 years: Schools face takeover by the state or a contracted private : Schools face takeover by the state or a contracted private education firm.education firm.

Taken from Peterson at http://www.stateline.org/live/ViewPage.action?Taken from Peterson at http://www.stateline.org/live/ViewPage.action?siteNodeId=136&languageId=1&contentId=41611 siteNodeId=136&languageId=1&contentId=41611

Page 12: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

How Tennessee Measures AYPHow Tennessee Measures AYP TCAP and writing tests are taken in elementary and middle TCAP and writing tests are taken in elementary and middle

school.school. Three Gateway tests are required to graduate: Algebra I, Three Gateway tests are required to graduate: Algebra I,

Biology I, and English II. There is also an 11Biology I, and English II. There is also an 11thth grade writing grade writing assessment. assessment.

The number of items correct to pass the Algebra I test is 30 The number of items correct to pass the Algebra I test is 30 (out of 62). Advanced students have answered 42 correctly.(out of 62). Advanced students have answered 42 correctly.

To be proficient on the English II Gateway, 26 questions must To be proficient on the English II Gateway, 26 questions must be answered correctly (out of 62). To be advanced, 39 must be answered correctly (out of 62). To be advanced, 39 must be correct. be correct.

Some additional end-of-course tests are taken for statistical Some additional end-of-course tests are taken for statistical purposes only.purposes only.

Graduation rate is key for high school AYP; the TN long-term Graduation rate is key for high school AYP; the TN long-term goal is 90% (http://www.all4ed.org/files/Tennessee_grp.pdf).goal is 90% (http://www.all4ed.org/files/Tennessee_grp.pdf).

Page 13: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

The Catch-It’s State-by-State!The Catch-It’s State-by-State! In order to reach AYP (and to reach 100% proficiency In order to reach AYP (and to reach 100% proficiency

by 2014), some states are being tougher than others.by 2014), some states are being tougher than others. ““This has produced a dizzying array of This has produced a dizzying array of

incomprehensible results. In the first estimate of the incomprehensible results. In the first estimate of the law’s impact, Michigan was found to be home to 1,500 law’s impact, Michigan was found to be home to 1,500 failing schools, while Arkansas had none. Most people failing schools, while Arkansas had none. Most people didn’t think this made any sense in terms of those two didn’t think this made any sense in terms of those two states’ usual performances on tests.” (Gerald W. states’ usual performances on tests.” (Gerald W. Bracey, Bracey, Setting the Record Straight: Responses to Setting the Record Straight: Responses to Misconceptions About Public Education in the U.SMisconceptions About Public Education in the U.S., p. ., p. 72)72)

What should be done about this, if anything?What should be done about this, if anything?

Page 14: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

And so we have national tests…And so we have national tests…

http://docs.google.com/gview?a=v&q=cache:vD1-0QrcweAJ:phs.prs.k12.nj.us/http://docs.google.com/gview?a=v&q=cache:vD1-0QrcweAJ:phs.prs.k12.nj.us/guidance/SAT_ACT_Comparison.pdf+SAT+vs.guidance/SAT_ACT_Comparison.pdf+SAT+vs.+ACT+scores&hl=en&gl=us&sig=AFQjCNEpfwrxk1aq0-RTru0Bvc2oKoXetA +ACT+scores&hl=en&gl=us&sig=AFQjCNEpfwrxk1aq0-RTru0Bvc2oKoXetA

Page 15: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Other DifferencesOther Differences According to an article in the According to an article in the New York TimesNew York Times, “the ACT is , “the ACT is

curriculum-based, while the SAT is aimed more at general curriculum-based, while the SAT is aimed more at general reasoning and problem-solving skills.”reasoning and problem-solving skills.”

““The ACT lasts two hours, 55 minutes (plus 30 minutes with The ACT lasts two hours, 55 minutes (plus 30 minutes with the optional writing test). The SAT lasts three hours, 45 the optional writing test). The SAT lasts three hours, 45 minutes.”minutes.”

“‘“‘The bright underachievers who are bored and get through The bright underachievers who are bored and get through school using one quarter of their brains will do better on the school using one quarter of their brains will do better on the SAT, because you just need good reasoning skills for that,’ SAT, because you just need good reasoning skills for that,’ says Scott White [a guidance counselor]. ‘And the says Scott White [a guidance counselor]. ‘And the overachievers, I don’t want to call them grinds, but they’re the overachievers, I don’t want to call them grinds, but they’re the ones who get the highest grades in the toughest classes ones who get the highest grades in the toughest classes because they work really hard, will do better on the ACT.’” because they work really hard, will do better on the ACT.’” (http://www.nytimes.com/2007/11/04/education/edlife/guidan(http://www.nytimes.com/2007/11/04/education/edlife/guidance.html). ce.html).

Page 16: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Why Are ACT Scores Important Why Are ACT Scores Important (Besides Getting into College)?(Besides Getting into College)?

““As part of our empirical definition of college readiness, ACT As part of our empirical definition of college readiness, ACT has established its College Readiness Benchmarks, which are has established its College Readiness Benchmarks, which are the typical ACT scores that are used to place students into the typical ACT scores that are used to place students into particular entry-level college courses across the United States: particular entry-level college courses across the United States: English Composition, College Algebra, introductory social English Composition, College Algebra, introductory social science courses (such as Economics and U.S. History), and science courses (such as Economics and U.S. History), and Biology. A student who meets a particular Benchmark has a Biology. A student who meets a particular Benchmark has a 50 percent chance of earning a grade of B or above, or a 75 50 percent chance of earning a grade of B or above, or a 75 percent chance of earning a grade of C or above, in the percent chance of earning a grade of C or above, in the corresponding college course. Students who take the ACT can corresponding college course. Students who take the ACT can therefore interpret their scores relative to these Benchmarks as therefore interpret their scores relative to these Benchmarks as another indicator of their readiness for college.”another indicator of their readiness for college.”

-www.act.org-www.act.org

Page 17: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

SAT vs. ACT By StateSAT vs. ACT By State

So we know that North Carolina spends more money on education then Mississippi (and is home to many fine higher education institutions!). Why, then, was Mississippi’s average SAT score higher than North Carolina’s in the early 90’s?

Blue = SAT

Red = ACT

Page 18: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Know Your Population!Know Your Population! Socioeconomic status and background are very Socioeconomic status and background are very

important to consider when looking at test scores.important to consider when looking at test scores. Similarly, “The test makers’ statistics also indicate Similarly, “The test makers’ statistics also indicate

that members of minority groups score better across that members of minority groups score better across the board on the SAT than on the ACT. But that can the board on the SAT than on the ACT. But that can be explained… Top students in all ethnic groups tend be explained… Top students in all ethnic groups tend to take the SAT, while some Midwestern states to take the SAT, while some Midwestern states require all juniors to take the ACT, thus lowering the require all juniors to take the ACT, thus lowering the mean.” (Slatalla, mean.” (Slatalla, http://www.nytimes.com/2007/11/04/education/edlifehttp://www.nytimes.com/2007/11/04/education/edlife/guidance.html)./guidance.html).

Why would more top achievers take the SAT? Why would more top achievers take the SAT?

Page 19: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Another ExampleAnother Example The SAT had not been “recentered” since its average The SAT had not been “recentered” since its average

raw score was set at 500 in 1941. 500 was set by raw score was set at 500 in 1941. 500 was set by “10,654 students mostly living in New England and “10,654 students mostly living in New England and New York. Ninety-eight percent of them were white, New York. Ninety-eight percent of them were white, 61 percent were male, and 41 percent had attended 61 percent were male, and 41 percent had attended private college-preparatory high schools.”private college-preparatory high schools.”

Why was there a 20-year decline in the average score Why was there a 20-year decline in the average score after 1963?after 1963?

The SAT was eventually “recentered” in 1995 with The SAT was eventually “recentered” in 1995 with scores of MANY more test takers! scores of MANY more test takers!

This is featured in Bracey’s This is featured in Bracey’s Setting the Record Setting the Record Straight.Straight.

Page 20: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

A Few DefinitionsA Few Definitions Population- The entire group of individuals about Population- The entire group of individuals about

which we want informationwhich we want information Sample- A part of the population from which we Sample- A part of the population from which we

actually collect information, used to draw conclusions actually collect information, used to draw conclusions about the wholeabout the whole

Convenience sample- Sample selected by taking the Convenience sample- Sample selected by taking the members of the population that are easiest to reach; members of the population that are easiest to reach; ex. mall surveysex. mall surveys

A simple random sample of size n consists of n A simple random sample of size n consists of n individuals from the population chosen in such a way individuals from the population chosen in such a way that every set of n individuals has an equal chance to that every set of n individuals has an equal chance to be the sample actually selected.be the sample actually selected.

Page 21: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

More DefinitionsMore Definitions Outlier-An individual value that falls outside the Outlier-An individual value that falls outside the

overall patternoverall pattern Variable-Any characteristic of an individual. A Variable-Any characteristic of an individual. A

variable can take different values for different variable can take different values for different individuals.individuals.

Confounded variables- Variables whose effects on the Confounded variables- Variables whose effects on the outcome cannot be distinguished from each otheroutcome cannot be distinguished from each other

What are some confounded variables possible for an What are some confounded variables possible for an outcome of low test scores?outcome of low test scores?

*All definitions taken from COMAP.*All definitions taken from COMAP.

Page 22: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

ACT, PLAN, and ExploreACT, PLAN, and Explore

We have two populations: one that has taken the We have two populations: one that has taken the Explore and the PLAN, another who has taken the Explore and the PLAN, another who has taken the PLAN and ACT. PLAN and ACT.

The tests are designed so 75% of test takers fall into The tests are designed so 75% of test takers fall into the interval given by the previous test. What should the interval given by the previous test. What should this look like graphically?this look like graphically?

How much do students have to improve to fall within How much do students have to improve to fall within their predicted range?their predicted range?

How should we sample these populations to get true How should we sample these populations to get true representations of them? representations of them?

Page 23: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Reality Hits!Reality Hits!

For some reason, students with disabilities For some reason, students with disabilities were underrepresented.were underrepresented.

Many students took only one or the other, not Many students took only one or the other, not both. There was also a LOT of missing data.both. There was also a LOT of missing data.

Many students had already taken the ACT and Many students had already taken the ACT and so did not retake on the school test day. What so did not retake on the school test day. What kind of scores would we have expected of kind of scores would we have expected of them?them?

Page 24: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

What do we do now?What do we do now?

We look at trimmed means (taking 10%, for We look at trimmed means (taking 10%, for example, from both ends of the data) or the example, from both ends of the data) or the median instead of the mean. Which one is median instead of the mean. Which one is better?better?

This gets rid of some of our outliers, but are This gets rid of some of our outliers, but are our outliers significant? Let’s take a look at our outliers significant? Let’s take a look at the data…the data…

Page 25: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Explore Average ScoresExplore Average Scores

0

5

10

15

20

25

English Math Reading Science Composite

JCAverage

NationalAverage

Page 26: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Explore BenchmarksExplore Benchmarks

0

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6070

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English Math Reading Science

JC % MetNational % Met

Page 27: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

PLAN Average ScoresPLAN Average Scores

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English Math Reading Science Composite

JC AverageNational Average

Page 28: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

PLAN BenchmarksPLAN Benchmarks

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English Math Reading Science

JC % Met

National % Met

Page 29: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

PLAN Results from Explore PLAN Results from Explore PredictionsPredictions

0102030405060708090

100

BelowPredicted

Range

WithinPredicted

Range

AbovePredicted

Range

%

Page 30: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Explore vs. PLAN Average Explore vs. PLAN Average PercentilesPercentiles

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English Math Reading Science Composite

ExplorePercentile

PLANPercentile

Page 31: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

ACT Average ScoresACT Average Scores

02468

1012141618202224262830323436

English Math Reading Science Composite

JC Average

State Average

NationalAverage

Page 32: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

ACT Results from PLAN ACT Results from PLAN PredictionsPredictions

0102030405060708090

100

BelowPredictions

WithinPredictions

AbovePredictions

%

Page 33: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

ACT vs. GatewayACT vs. Gateway

0

1020

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5060

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90100

English/Reading Math Science

% Met ACTBenchmark

% Advanced onGateway

Page 34: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Explore, PLAN, and ACT Average Explore, PLAN, and ACT Average Percentiles* Percentiles*

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English Math Reading Science Composite

Explore Percentile

PLAN Percentile

ACT Percentile

* Not the same students tested on all three tests

Page 35: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

ACT BenchmarksACT Benchmarks

0

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English Math Reading Science All Four Met

JC % Met

State % Met

National % Met

Page 36: Educational Statistics: Avoiding Population and Sampling Pitfalls Meredith Wachs

Takeaway PointsTakeaway Points ACT, not Gateway, standards and testing will tell us ACT, not Gateway, standards and testing will tell us

more about instruction and better prepare students for more about instruction and better prepare students for the future (especially post-secondary education), the future (especially post-secondary education), while fulfilling the Gateway standards.while fulfilling the Gateway standards.

This data is only helpful if it is: This data is only helpful if it is: 1. Recorded1. Recorded2. Analyzed every year2. Analyzed every year3. Reflective of true efforts by 3. Reflective of true efforts by everyevery student student

How do we motivate non-college-bound students? How do we motivate non-college-bound students? What else can we do with this kind of data (if What else can we do with this kind of data (if

sampled better)? sampled better)?