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NPSAS DAS Training. December 2006 Training Shefali V. Mehta Minnesota Office of Higher Education. NPSAS Background. NPSAS 2004 Data Based on training by: Lutz Berkner of MPR Associates, Inc. Tracy Hunt- White and James Griffith of the National Center for Education Statistics.
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NPSAS DAS Training December 2006 Training Shefali V. Mehta Minnesota Office of Higher Education
NPSAS Background NPSAS 2004 Data Based on training by: Lutz Berkner of MPR Associates, Inc. Tracy Hunt- White and James Griffith of the National Center for Education Statistics
What is the National Postsecondary Student Aid Survey? • The National Postsecondary Student Aid Survey, or NPSAS, is a nationally-representative stratified random sample of undergraduate, graduate and first-professional students attending postsecondary institutions. • Today’s presentation will focus on the undergraduate sample data- how it was collected, what it contains and how to access and use it. Minnesota Office of Higher Education
NCES’ Recent Surveys: Higher Education Longitudinal and Cross-Sectional Studies Minnesota Office of Higher Education
Data Sources for the NPSAS 2004 • Central Processing System (CPS) Match • Institutional Records (CADE) • Student Interviews • NSLDS Loan Match • NSLDS Pell Grant File Match • ETS File Match • ACT File Match Minnesota Office of Higher Education
NPSAS 2004 Data Collection Timeline Minnesota Office of Higher Education
Products related to NPSAS • Public Use Data Systems (DASs) • Methodology Reports describing study design, procedures, and outcomes • Restricted use research files • ED Tabs and Descriptive Reports based on analyses of merged data. Minnesota Office of Higher Education
Using the DAS online Accessing the NPSAS 2004 Data
What is the DAS? • The Data Application System, or DAS, is a software application that produces tables and correlation matrices for NCES datasets. • The DAS, which is available for each NCES dataset, includes • Over 1,000 variables with full descriptions and • Statistical information, such as standard errors and the distribution of the data. • It is available online through the NCES website: http://nces.ed.gov/dasol/ Minnesota Office of Higher Education
DAS Home Page:http://nces.ed.gov/das/ Minnesota Office of Higher Education
DAS Onlinehttp://nces.ed.gov/dasol/ Minnesota Office of Higher Education
DAS Online: Select a dataset Minnesota Office of Higher Education
DAS Online Minnesota Office of Higher Education
NCES Data Usage Agreement Select “I agree..” to continue to the DAS for NPSAS 2004. Note: To use DAS online, you need to enable pop-up windows from this website. The application relies heavily on pop-up windows, such as this usage agreement. Minnesota Office of Higher Education
DAS Online Window Toolbar Minnesota Office of Higher Education
DAS Online Window Subject Category Topic Subtopic Minnesota Office of Higher Education
DAS Online Window Variable list Blue = continuous variable Green = categorical variable Red = weight Minnesota Office of Higher Education
Available variables Click on the “view/download list of variables” link to see all available variables. Minnesota Office of Higher Education
Locating variables in the NPSAS There are two ways to select variables. The first is through the drop-down menus available on the main page. The menus are organized in the following categories: • Frequently Used:Variables • Aid: Application, Federal, Grants, Institutional, Net Price, Outside, Package, Ratio, State, Total • Background:Demographics, Family, Residence • Education:Attendance, Program • Employment:Description, Employer, Future, Licensure, Status, While Enrolled • Finances:Income • Institution:Other, Price, Type • Parent:Education, Family • Public Service:Participation • Survey:Sample, Weights Minnesota Office of Higher Education
Locating variables in the NPSAS The second way to locate a variable is by clicking on the “Search for variable” link on the toolbar. This pop-up window will appear. Minnesota Office of Higher Education
Using the DAS online Using the Variable Tags
What kind of estimates can the DAS produce? • Means (including observations = 0) • Averages (of observations > 0) • Percent distributions • Percent positive (or greater than a selected value) • Percentiles (10th, 25th, 50th, 75th, and 90th) (with or without observations = 0) • Medians (the 50th centile) or • Correlation matrices Minnesota Office of Higher Education
Variable Description Window • Each variable window contains the following: • a description of the variable • the sources for the variable Minnesota Office of Higher Education
Variable Description Window And the distribution of the variable. In this case, 63.2 percent of the data has a value for the total amount received. The range for this variable is $50-$56,740. Remember- this information is for the national level, each state has its own distribution. Minnesota Office of Higher Education
Select a Tag for the Variable Click on the “Select a tag” tab to show the tag options available for the variable. These “tags” tell you the various ways this variable can be represented in your table. Minnesota Office of Higher Education
Using the DAS online Practice exercises to illustrate the tags
NPSAS - Exercise 1 What is the percent distribution of full-time, full-year undergraduates according to degree program and gender, by dependency status, institution sector, aid status, and age? Find the percentage of full-time, full-year independent male students who attended a public 4-year institution. Minnesota Office of Higher Education
Exercise 1 – Breakdown Run 1 – What is the percent distribution of undergraduates according to degree program, by dependency status and institution sector? Run 2 – What is the percent distribution of undergraduates according to degree program, by dependency status, institution sector, aid status, and age? Run 3 – What is the percent distribution of full-time, full-year undergraduates according to degree program and gender, by dependency status, institution sector, aid status, and age? Minnesota Office of Higher Education
Tags: Column_Cat • Creates percentages for each category of a variable • Missing values and legitimate skips are not included in any of the categories • Responses coded as “0” are not included • Pertains to categorical variables only Also applies to: Row_Cat, Span_Cat, By_Cat Minnesota Office of Higher Education
Tags: Row_Cat • Similar to Column_Cat • Creates a row of estimates for each category • Responses coded as “0” are not included • Pertains to categorical variables only Also applies to: Column_Cat, Span_Cat, By_Cat Minnesota Office of Higher Education
Tags: Row_Lump • Creates customized categories by grouping existing variable categories • Responses coded as “0” can be included • Legitimate skips can be excluded or included in the new categorization • Allows reordering of existing categories • Pertains to categorical variables only Also applies to: Column_Lump, Span_Lump, By_Lump Minnesota Office of Higher Education
Tags: Row_Cut • Divides a continuous variable into categories by specifying ranges • Creates a row of estimates for each category • Specify beginning cut-point value in each range • Cut-point must be a number with a decimal (e.g., 10.5) Also applies to: Column_Cut, Span_Cut, By_Cut Minnesota Office of Higher Education
Tags: Row_Cut Range 1: (>= -0.5 and < 0.5) includes 0 2: (>= 0.5 up to infinity) at least $1 in aid Range 1: (>= 0.5 and < 18.5) 2: (>= 18.5 and < 23.5) 3: (>= 23.5 and < 29.5) 4: (>= 29.5 up to infinity/max value) Minnesota Office of Higher Education
Tags: Filter Or_Filter • Subsets (focuses on) the population of interest • If any condition is met (filter is selected) the case will be included And_Filter • Subsets (focuses on) the population of interest • All conditions have to be met (filters selected) in order for case to be included Minnesota Office of Higher Education
Tags: Filter Integer filter: Limit population to the categories selected. Cut-point filter: Limit population to those with values greater than or less than a specific point or between two points. Minnesota Office of Higher Education
Tags: Span_Cat • Uses all of a variable’s categories to group sets of rows in the table • Creates a subtable of estimates for each variable category • Does not provide an overall summary table • Warning: Drastically increases the number of estimates in the table See also: Span_Cut, Span_Lump Minnesota Office of Higher Education
NPSAS - Exercise 2 What percentage of full-time, full-year undergraduates received financial aid by dependency status, institution sector, and age? What was the average amount they received? Steps: Import exercise 1 Delete Column_Cat and Span_Cat tags Delete Row_Cut tag for Total Aid Add Percent and Average tags Minnesota Office of Higher Education
Tags: Percent> • Defines a column of percentages based on values greater than a specified cut point • Can be used with the Mean and Average>0 tags Minnesota Office of Higher Education
Tags: Mean versus Average • Mean will include zeros in the denominator • Average will not include zeros in the denominator Minnesota Office of Higher Education
Mean vs. Average All respondents, including those with no aid Only respondents who have aid Minnesota Office of Higher Education
Tags: By_Cat • Creates a column of Average, Mean, or Percent> estimates for each category of a variable • Can be used with only ONE Mean, Average>0, or Percent> variable • Provides an overall summary column • Will increase the size of your table See also: By_Cut, By_Lump Minnesota Office of Higher Education
Example of By_Cat with Percent> • Percent> yields percent FT, full-year UG with aid • By_Cat generates percent FT, full-year UG with aid by degree program. Ex: 77.4% of FT, full-year UG in a certificate degree program received aid. Minnesota Office of Higher Education
Representative Sample States NPSAS:04 is not designed to be representative at the state level except for undergraduates attending public 2-year, public 4-year, and private not-for-profit 4-year institutions in the 12 specific states. Use these to look at these representative sample states: - INSTSAST (NPSAS institution representative sample states) - INSTSTSE (NPSAS institution representative state sample by sector) Do not use: INSTSTAT (NPSAS institution state) Minnesota Office of Higher Education
Tags: Centile vs. Centile>0 • Generates percentile columns from continuous variables • Produces the cut points for the following percentiles: 10th, 25th, 50th, 75th, 90th • Median = the 50th centile -- the value above and below which half of the observations lie • Centile includes zero values • Centile>0 excludes zero values Minnesota Office of Higher Education
Example of Centile>0 Note: Last column shows the percentage of FT, FY undergraduates who received no aid. Minnesota Office of Higher Education
Using the DAS online Saving, modifying and loading files: .tpf files
Saving tables you created • You can save the parameter file for re-use and modification • Files containing the specifications for tables are called .tpf files, or table parameter files • After creating a file in the DAS window, click on Save in the toolbar. • The .tpf file will be saved to the location specified by you Minnesota Office of Higher Education
Uploading tables to the DAS application • Click on Import in the toolbar. • Locate the .tpf file to be uploaded and upload it. • Note: for the DAS online application to read the file, they must be saved with the extension .tpf • Once the file is uploaded, it can be altered and run as usual. Minnesota Office of Higher Education
Reproducing or modifying tables created by others • You can download and use any parameter file used to create a report or ED Tab from our web site: http://nces.ed.gov/das • .tpf files can be edited in a text editor (such as Notepad or Wordpad) but they must be saved with the .tpf extension (not the .txt default extension) Minnesota Office of Higher Education
Using the batch processor • The batch processor allows you to run several tpfs at once • You must create an account and log-in by clicking on “Batch processor” on the left-hand side of http://nces.ed.gov/dasol/ • The files must be in added to a .zip file and then uploaded. After uploading the file, COPY down your batch number to retrieve your files Minnesota Office of Higher Education