440 likes | 548 Views
Operational CBT Implementation Issues: Making It Happen. Richard M. Luecht, PhD Educational Research Methodology University of North Carolina at Greensboro.
E N D
Operational CBT Implementation Issues: Making It Happen Richard M. Luecht, PhD Educational Research Methodology University of North Carolina at Greensboro Tenth Annual Maryland Assessment Conference: COMPUTERS AND THEIR IMPACT ON STATE ASSESSMENT: RECENT HISTORY AND PREDICTIONS FOR THE FUTURE. 18-19 October, College Park MD
What do you get if you combine a psychometrician, a test development specialist, a computer hardware engineer, a LSIsoftware engineer, a human factors engineer, a QC expert, and a cognitive psychologist? A pretty useful individual to have around if you’re implementing CBT!!!!
Ui=010120113 Response Vector Item Bank Test Delivery Network Examinee Item Selection/Test Assembly Algorithm Ability Estimation/Scoring Algorithm A Naïve View of Operational CBT* * Includes linear CBT, CAT, CMT CAST and other variants
The Challenge of CBT • Moving more complex data more quickly, more securely and more accurately from item generation through final scoring • Immediate responsiveness where possible • Re-engineering data management and processing systems: end-to-end • 99.999999% accuracy and eliminating costly and error-prone human factors through automation and better QC/QA
Systems Impacted by Redesign and QC/QA • Item development and banking • Test assembly and composition • Examinee eligibility, registration, and scheduling, fees • Test delivery • Psychometrics and post-examination processing • Item analysis, key validation and quality assurance • Test analysis • Final scoring, reporting and communication
Item-Level Data • Item or exercise rendering data • Stimulus information (e.g., MCQ stem, a reading passage) • Response display labels (e.g., distractors as labels for a check box control) • Scripts for interactivity • Template references • Content and other item attributes • Content category codes • Cognitive and other secondary classifications • Linguistic features
Item-Level Data – cont. • Statistical item data • Classical item statistics (p-values, biserial correlations, etc.) • IRT statistics (1PL, 2PL, 3PL, GPCM parameter estimates) • DIF statistics and other special indices • Operational data • Reuse history • Exposure rates and controls (for CAT) • Equating status
Test Unit Data • Object list to include (e.g., item identifies for all items in the test unit) • Navigation functions, including presentation, review and sequencing rules • Embedded adaptive mechanisms (score + selection) • Timing controls and other information (e.g., how clock functions, time limit, etc.) • Title and instruction screens
Test Unit Data – cont. • Presentation template references • Helm look-and-feel (navigation style, etc.) • Functions (e.g., direction of cursor movement after ◄┘ or tab is pressed) • Reference and ancillary look-up materials • Calculators • Hyperlink to other BLOBs • Custom exhibits available to test takers
Examinee Data • Identification information • Name and identification numbers • Photo, digital signature, retinal scan information • Address and other contact information • Demographic information • Eligibility-to-test information • Jurisdiction • Eligibility period • Retest restrictions
Examinee Data – cont. • Scheduled test date(s) • Special accommodations required • Scores and score reporting information • Testing history and exam blocking • Security history (e.g., previous irregular behaviors, flagged for cheating, indeterminate scores, or large score gains) • General correspondence
Interactions of Examinee and Items or Test Units • Primary information • Final responses • Captured actions/inactions (state and sequencing of actions) • Secondary information • Cumulative elapsed time on “unit” • Notes, marks or other captured during testing
Response Processing in CBT • Response capturing agents convert examinee responses or actions to storable data representations • Examples • item.checkbox.state (T/F) item.response.choice=“A” {A,B,C,D} • item.group.unit(j).state (T/F), j=1,…6 item.response.choice=“1,4” {1,2,3,4,5,6} • item.component.text(selected=position,length) item.response.text=“text” • item.component.container(freeresponse.entry) item.response.text=“text” • case.grid.cellRowCol(numeric.entry) case.grid.cellref.response.text=“value”
Raw Response Representations for Discrete Items Convert to item002.response.choice=“3”
Raw Response Representations for a Performance Exercise Convert to… caseA.tab5.sheet001.r3c4.text=“12501.99”
Raw Response Representations for an Essay Store as… RichTextBox.Item001.text=“There were two important changes that characterized the industrial revolution. First, individuals migrated from rural to urban settings in order to work at new factories and in other industrial settings (geographic change). Second, companies began adopting mechanisms to facilitate mass production (changes in manufacturing procedures, away). ”
Entering the Psychometric Zone: Data Components of Scoring Evaluators • Responses • Selections, actions or inactions: item.response.state=control.state (ON or OFF) • Entries: item.response.value=control.value • Answer expressions (rethinking IA is needed) • Answer keys • Rubrics of idealized responses or patterns of responses • Functions of other responses • Score evaluators process the responses • Scoring evaluators convert the stored responses to numerical values—e.g., f(responseij, answer keyi)xij[0,1] • Raw scoring or IRT scoringaggregation and scaling of item-level numerical scores
Planning for Painless Data Exchanges and Conversions • Systems and subsystems need to exchange data on a regular basis, providing different views and field conversions • The hand-off must have several fool-proof QC steps • Verification of all inputs • Conversion success 100% verified • Reconciliation of all results, including counts, discrepancies, missing values, etc.
Example of a (Partial) Examinee’s Test Results Record testp>wang>marcus>>605533641>0A1CD9>93bw100175>1>>501>001>ENU>CB1_CAST105>>90>0>0>0>DTW>06/26/96>08:41:38>05:58:32>w10>2>apt 75>1000 soldiers field rd>north fayette>IN>47900>USA>1>1235552021>>NOCOMPANYNAME>0>>>>>1>1235551378>>0>0>35>>142/218/0/u>1>-1>7>CBSectionI.12>CB1>s>p>0>36>>72/108/0/u>Survey015>survey15>s>p>0>0>>0/0/0/u>CBSectionI>CAST2S1>s>p>0>28>>28/62/0/u>CBSectionII>CAST2S4>s>p>0>42>>42/48/0/u>CBSectionII>CAST2S3>s>p>0>0>>0/0/0/u>CBSectionII>CAST2S2>s>p>0>0>>0/0/0/u>Survey016>survey2>s>p>0>0>>0/0/0/u>0>372>SAFM0377>2>0>E>5>s>E>1>76>>SAEB0549>2>0>D>5>s>A>0>68>>SAFM0378>2>0>A>5>s>A>1>72>>SAAB1653>2>0>C>5>s>D>0>102>>SABA8868>2>0>B>5>s>C>0>85>>SCAA1388>2>0>E>8>s>E>1>53>>SAAA8447>2>0>D>5>s>E>0>55>>SAAB1934>2>0>A>5>s>A>1>60>>SAAB2075>2>0>E>5>s>E>1>136>>SADA7710>2>0>D>5>s>D>1>40>>SABB1040>2>0>B>5>s>E>0>46>>SCAA1396>2>0>H>10>s>A>0>93>>SACA8906>2>0>D>5>s>E>0>75>>SADA8116>2>0>C>5>s>D>0>53>>SADA8673>2>0>B>5>s>B>1>41>>SACA8626>2>0>B>5>s>D>0>48>>SAFM0374>2>0>C>5>s>D>0>80>>SABA6397>2>0>A>5>s>A>1>110>>SAAB1088>2>0>C>5>s>C>1>55>>SACA8455>2>0>D>4>s>D>1>73>>SAAB1667>2>0>C>5>s>C>1>44>>SAAJ7633>2>0>C>5>s>C>1>89>>SABA5745>2>0>D>5>s>A>0>43>>SCAA1389>2>0>B>8>s>H>0>61>>SADA8650>2>0>A>5>s>C>0>39>>SAFB0112>2>0>C>5>s>C>1>132>>SAAB2513>2>0>B>5>s>B>1>120>>SAFA9248>2>0>E>5>s>A>0>77>>SABJ1042>2>0>D>5>s>C>0>112>>SACJ5894>2>0>C>5>s>D>0>82>>SAAA0410>2>0>D>5>s>E>0>89>>SAAB1681>2>0>C>5>s>C>1>88>>SAFM0365>2>0>A>5>s>A>1>65>>SAEA8980>2>0>A>5>s>B>0>52>>
Assessment XML <?xml version="1.0" encoding="UTF-8"?> <AssessmentResultxmlns="http://ns.hr-xml.org/2004-08-02" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://ns.hr-xml.org/2004-08-02 AssessmentResult.xsd"> <ClientIdidOwner="Provider Inc"> <IdValue name="ClientCode">OurClient-1342</IdValue> </ClientId> <ProviderIdidOwner="Customer Inc"> <IdValue>ePredix</IdValue> </ProviderId> <ClientOrderId> <IdValue name="PO Number">53RR20031618</IdValue> <IdValue name="Department Name">Administration</IdValue> </ClientOrderId> <Results> <Profile>Customer Service</Profile> <OverallResult> <Description>Executive Manager</Description> <Score type="raw score">51</Score> <Score type="percentile">65</Score> <Scale>40-60</Scale> </OverallResult> <AssessmentStatus> <Status>In Progress</Status> <Details>Remains: "GAAP Basic Knowledge"</Details> <StatusDate>2003-04-05</StatusDate> </AssessmentStatus> <UserArea/> </AssessmentResult>
Translating XML Entities to a Data Structure XML Parser Structured Data
Extracting Data Views • A data view is a set of restructuringfunctions that produce a data set from raw data • Views begin with a query • Usually results a formatted file structure • Graphing functions produce graphic data sets • Database functions produce database record sets • Multiple views are possible for different uses (e.g., test assembly, item analysis, calibrations, scoring) • Well-designed views are reusable • Standardized queries of the database(s) • Each views as a template with “object” status • Views can be manipulated by changing their properties (e.g., data types, presentation formats)
Types of Data Files (Views) • Implicit Files: File format implies a structure for the data • Flat files with fixed columns (headers optional) • Comma, tab or other delimited files • Explicit Files: Variables, data types, formats and the actual data are explicitly structured • Data base files: dBASE, Oracle, Access, etc. • Row-column worksheets with “variable sets” (e.g., Excel in data mode, SPSS) • XML and SGML
Structure of the Flat File(A Type of “Metadata”) Data Type Definitions Presentation View Data
Query Test Form and Item Databases SELECT Item.Records IF(Query_Conditions=TRUE) Sort Item.ID
The P IQuery SELECT Examinee.Records IF(Query_Conditions=TRUE)
The P IQuery GENERATE.FLATFILE(Examinee.Records,Item.Records) Generate “Masked” Response File 107555 9919911019991009 517101 1190199990019991 .PersonID Items fromTST0181 & TST0183
Implied Flat File View of Test Data(Person by Item Flat Files) Example 1: “raw response vectors” (input to commercial item analysis software) 00001 BDCAABCAEDACBD 00002 BDBAABDAEDBCBD 00003 BCCBABCAEDABBD Example 2: “scored response vectors” (input to commercial item calibration software) 00001 11111111111011 00002 11011101110011 00003 10101111111100
Reconciliation 101 • Definitions: bringing into harmony, aligning, balancing • Reconciliation is essential for CBT data management and quality assurance • Test forms, items, sets, examinees, and transaction output counts match input counts • Results match expectations or predictions
Reconciliation Example (Examinee Data for IA/Calibrations) File Reconcilation and Rectangular File Creator (R. Luecht, [c] 2009, 2010) Date/time: mm-dd-yyhh:mm:ss Control File: ControlFile.CON Examinee_Test_Form File: ActiveExamineeTestForm.txt NP = 1687 Treatment of (Score_Status=1) items: INCLUDE Items and Responses Item File: MasterItemFile.DAT NI = 3857, Total Read = 3857 Excluded= 0 =========================================================== Active_Examinee_Responses File=ActiveExamineeResponse.txt No. IDs (from Active_Examinee_Test_Form)= 1687 File size (examinee transactions)= 506100 No. nonblank records input = 506100 No. records with unmatched items = 0 Forms = 8 1687 scored response records saved to Data-ResponseFile-Scored.RSP 1687 raw response records saved to Data-ResponseFile-Raw.RAW ITEM LISTING and FORM ASSIGNMENTS DETECTED ID IdentifierNOptOptsN-CountNFrmForms Item_21801 5 ABCDE 41 1 04 Item_24601 5 ABCDE 97 3 01 03 07 Item_29801 5 ABCDE 97 2 02 07 : <only partial records included to conserve space> MISMATCH SUMMARY ---------------- NO unmatched item IDs to FORMS NO unmatched item IDs to RESPONSE RECORDS Item Counts by Form
Follow the Single-Source Principle • A unique master record should exist for every entity • Examinees registered/eligible to test • Items • Item sets • Modules, testlets or groups • Test forms • Changes should be made to the master and forward-propagated for all processing
Example of Single Source YES!! NO!
Ignorable Missing Data? • Very little data is missing completely at random, limiting the legitimate use of imputation • Some preventable causes of missing data • Lost records due to crashes/transmission errors • Corrupted response capturing/records • Purposeful omits • Running out of time/motivation to finish
Challenges of Real-Time Test Assembly (CAT or LOFT) • Real-time item selection requires high bandwidth and fast servers and pre-fetch reduces precision • A “test form” does not exist until the examination is complete • QC of test forms is very difficult, except by audit sampling and careful refinement of test specifications (objective functions/constraints) • QC of the data against “known” test-form entities is NOT possible
Thanks! Ric Luecht rmluecht@uncg.edu