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Timing Exercises (1-3)Timing Exercises (1-3)

E-Prime 2002 WorkshopE-Prime 2002 Workshop

Files on My Documents\My Experiments\Files on My Documents\My Experiments\Workshop\E-Prime ExercisesWorkshop\E-Prime Exercises

E-Prime Timing ExercisesE-Prime Timing Exercises

Copyright Psychology Software Tools Inc. 2002Copyright Psychology Software Tools Inc. 2002

These materials may be used for local educational purposes only. all These materials may be used for local educational purposes only. all other use requires approval in writing. Please send requests to other use requires approval in writing. Please send requests to

info@pstnet.cominfo@pstnet.com

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List of ExercisesList of Exercises 1. Varying Probe Duration – 1. Varying Probe Duration –

TimingParadigm3TimingParadigm3

2. Cumulative Timing of a Repeating 2. Cumulative Timing of a Repeating Sequence of Events – Sequence of Events – TimingParadigm4TimingParadigm4

3. Continuous sequences of events at 3. Continuous sequences of events at high rate with short stimulus times – high rate with short stimulus times – TimingParadigm5TimingParadigm5

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General Rule For TimingGeneral Rule For Timing Set the timing of the critical event to Set the timing of the critical event to

be equal the intended time rounded to be equal the intended time rounded to the nearest millisecond and set the nearest millisecond and set prerelease equal to greater than the prerelease equal to greater than the longest time to get ready for the next longest time to get ready for the next display. display.

Examples assume 60 Hz, 16.67ms Examples assume 60 Hz, 16.67ms refresh subtract set the prerelease to refresh subtract set the prerelease to 17 ms and refresh time of 17 ms and refresh time of Refreshes 60 72

1 17 142 33 283 50 42

Refresh Rate Hz

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Timing Exercise 1Timing Exercise 1

1. Open My Documents\My Experiments\Workshop\1. Open My Documents\My Experiments\Workshop\E-Prime Exercises\ TimingParadigm3 and run to E-Prime Exercises\ TimingParadigm3 and run to create an EDAT filecreate an EDAT file

2. Verify Display.RefreshRate2. Verify Display.RefreshRate

3. Use E-DataAid to arrange columns to check 3. Use E-DataAid to arrange columns to check timing accuracytiming accuracy

4. Copy columns into Excel4. Copy columns into Excel

5. Perform calculations using Excel5. Perform calculations using Excel

This exercise presents a masking experiments presenting This exercise presents a masking experiments presenting displays for 1-3 refreshes (17-50ms). In this exercise you will:displays for 1-3 refreshes (17-50ms). In this exercise you will:

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Timing Exercise 1- Verify Refresh Timing Exercise 1- Verify Refresh RateRate

1. Use E-DataAid to O1. Use E-DataAid to Open pen My Documents\My Experiments\My Documents\My Experiments\Workshop\E-Prime Exercises\ Workshop\E-Prime Exercises\ TimingParadigm3-3-1.EDAT TimingParadigm3-3-1.EDAT (which was previously created)(which was previously created)

2. Verify Display.RefreshRate2. Verify Display.RefreshRate

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Timing Exercise 1 – Arrange Timing Exercise 1 – Arrange ColumnsColumns

3. Select Arrange 3. Select Arrange Columns tools, Columns tools, click Remove All.click Remove All.

4. Next to the 4. Next to the Select button Select button type type *.OnsetTime; *.OnsetTime; ProbeDuration; ProbeDuration; Time* and click Time* and click SelectSelect

5. Click Add and 5. Click Add and click OKclick OK

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Timing Exercise 1- Copy to Timing Exercise 1- Copy to ExcelExcel

5. Arrange columns move 5. Arrange columns move Mask.OnsetTime after Mask.OnsetTime after Probe.OnsetTime. Click on Probe.OnsetTime. Click on column heading to select column heading to select then click & drag to move then click & drag to move

6. Select all columns, 6. Select all columns, copy, open Excel and copy, open Excel and paste.To select cellspaste.To select cells click on click on

Fixation.OnsetTime Fixation.OnsetTime heading and drag across to heading and drag across to TimeProbetoMask. TimeProbetoMask.

Go to Edit and select CopyGo to Edit and select Copy Open Excel Open Excel Paste (Ctrl-V) the cells into Paste (Ctrl-V) the cells into

the first cell of the the first cell of the spreadsheetspreadsheet

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Timing Exercise 1- Calculate Timing Exercise 1- Calculate ResultsResults

7. Calculate the 7. Calculate the Probe to Mask timeProbe to Mask time Create a Probe-Mask Create a Probe-Mask

columncolumn In first cell of that In first cell of that

column type the column type the formula: formula: =C2-B2=C2-B2

Copy formula down to Copy formula down to last row last row

Notes the times are Notes the times are about 17,33, and 50 about 17,33, and 50 msms

Compare to Compare to TimeProbeToMask TimeProbeToMask column, they should column, they should be the samebe the same

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Timing Exercise 1- Calculate Timing Exercise 1- Calculate ResultsResults

8. Calculate the 8. Calculate the Fixation to Probe timeFixation to Probe timeCreate a Fixation-Create a Fixation-

Probe columnProbe column In first cell of that In first cell of that

column type the column type the formula: =B2-A2formula: =B2-A2

Copy formula down to Copy formula down to last rowlast row

Note the times are Note the times are ~516 ms~516 ms

Compare to Compare to TimeFixationToProbe TimeFixationToProbe column, they should column, they should be the same be the same

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Timing Exercise 1- View ResultsTiming Exercise 1- View Results

If you know how to If you know how to use Excel pivot use Excel pivot tablestables, create a pivot , create a pivot table by selecting table by selecting columns ProbeDuration columns ProbeDuration to Mask-Probe, on Data to Mask-Probe, on Data menu, choose pivot menu, choose pivot table, press Next twice, table, press Next twice, choose Layout, Copy choose Layout, Copy and drag and drag ProbeDuration to row ProbeDuration to row and Mask-Probe to data and Mask-Probe to data twice, double click and twice, double click and select Average and select Average and StdDev as on the leftStdDev as on the left

Open My Documents\My Open My Documents\My Experiments\Workshop\E-Prime Experiments\Workshop\E-Prime Exercises\TimingExercises excel Exercises\TimingExercises excel spreadsheet and select spreadsheet and select Exercise1Pivot tabExercise1Pivot tab

View the calculated means and View the calculated means and SD of Probe and Mask time SD of Probe and Mask time

View the Pivot table of Probe-View the Pivot table of Probe-Mask based on ProbeDurationMask based on ProbeDuration

OR:OR:

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What would your report to a What would your report to a Journal?Journal?

Have Assistant verify your “Timing Report” Have Assistant verify your “Timing Report” before moving on. before moving on. Please put the display into this Please put the display into this form and raise your hand.form and raise your hand. Explain what would your Explain what would your put in a journal. put in a journal. Assistant InitialsAssistant Initials ___ ___

In this experiment the displays were presented with In this experiment the displays were presented with means and standard deviations for the probe to means and standard deviations for the probe to mask times of ___________________________mask times of ___________________________

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Exercise 1a (Optional) – Use Script to Exercise 1a (Optional) – Use Script to Log Time Between Stimulus Log Time Between Stimulus

OnsetsOnsets

You can add an Inline object and add You can add an Inline object and add script to calculate and log the onset to script to calculate and log the onset to onset time for later analysis in E-onset time for later analysis in E-DataAid.DataAid.

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Timing Exercise 1 Study Timing Exercise 1 Study QuestionsQuestions

Could you at this point answer these questions?Could you at this point answer these questions?1.1. What would expect if you ran this exercise on What would expect if you ran this exercise on

a 100 Hertz monitor if it is set up for a 60 Hertz a 100 Hertz monitor if it is set up for a 60 Hertz monitor?monitor?

2.2. What if the PreRelease were set to 0 what What if the PreRelease were set to 0 what would you expect the times to be on a 60 would you expect the times to be on a 60 Hertz monitor?Hertz monitor?

3.3. How might you put in code to detect if the How might you put in code to detect if the times were different from the intended time by times were different from the intended time by more than a millisecond and log the problem?more than a millisecond and log the problem?

4.4. How might you put in code to be sure that the How might you put in code to be sure that the program is running on a 60 Hertz monitor?program is running on a 60 Hertz monitor?

Short Answers are included in the Exercise AppendixShort Answers are included in the Exercise Appendix

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Timing Exercise 2Timing Exercise 2This exercise contrasts event mode and This exercise contrasts event mode and

cumulative mode timing. Cumulative mode cumulative mode timing. Cumulative mode minimizes cumulative time error in an minimizes cumulative time error in an experiment. In this exercise you will:experiment. In this exercise you will:

1. Run My Documents\My Experiments\1. Run My Documents\My Experiments\Workshop\E-Prime Exercises\Workshop\E-Prime Exercises\TimingParadigm4AllModes and analyze the TimingParadigm4AllModes and analyze the timing.timing.

2. Use E-DataAid to output graphs and table 2. Use E-DataAid to output graphs and table for Excelfor Excel

3. Report the problem errors in timing3. Report the problem errors in timing

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Timing Exercise 2 – Create or Open EDAT Timing Exercise 2 – Create or Open EDAT filefile

1. Either run 1. Either run TimingParadigm4AllModes.es TimingParadigm4AllModes.es oror use the existing file. use the existing file.

2. In E-DataAid o2. In E-DataAid open My pen My Documents\My Experiments\Documents\My Experiments\Workshop\E-Prime Exercises\Workshop\E-Prime Exercises\TimingParadigm4 and run or open TimingParadigm4 and run or open TimingParadigmAllModes100-TimingParadigmAllModes100-1.EDAT file for data (which was 1.EDAT file for data (which was previously created) with E-previously created) with E-DataAid.DataAid.

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Get Cumulative Time Get Cumulative Time GraphGraph

3. Click 3. Click CalculateCalculate

4. Move 4. Move over Trial, over Trial, TimingModTimingMode, e, PreReleasePreRelease, , TimingCumTimingCumulativeErroulativeError to cellsr to cells

5. Click 5. Click RunRun

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Examine Timing Send Examine Timing Send ExcelExcel

6. Select Plot6. Select Plot 7. Click Excel 7. Click Excel

PlotPlot

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Examine Timing DataExamine Timing Data 8. Look at timing data note difference 8. Look at timing data note difference

from intendedfrom intended

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Zoom in on Timing ErrorZoom in on Timing Error 9. Click on Excel Graph change chart 9. Click on Excel Graph change chart

mode to line graph.mode to line graph. 10. Click on the Y-axis and right click 10. Click on the Y-axis and right click

and set max Y to 50. Note differences and set max Y to 50. Note differences in errorsin errors

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Use E-DataAid to Output Timing Use E-DataAid to Output Timing TableTable

11. Return to E-11. Return to E-DataAid, change DataAid, change Analysis Analysis Set Rows to Set Rows to

TimingModeTimingModePreReleasePreRelease

Set Data toSet Data toTimeCumulativeErroTimeCumulativeErro

rTimerTimeTimeFixationToProbeTimeFixationToProbeTimeProbeToMaskTimeProbeToMask TimeProbeOnsetTo TimeProbeOnsetTo

Onset meanOnset mean Time ProbeOnsetTo Time ProbeOnsetTo

Onset SD of SampleOnset SD of Sample

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Export Table to ExcelExport Table to Excel 12. Export to Excel by selecting 12. Export to Excel by selecting

StatView format and Excel CopyStatView format and Excel Copy

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Identify Poor TimingIdentify Poor Timing 13. Identify poor timing cases (off by a 13. Identify poor timing cases (off by a

refresh cycle). Note cumulative 100 ms refresh cycle). Note cumulative 100 ms prerelease correct, errors in all other cases. prerelease correct, errors in all other cases.

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How would your run your experiment?How would your run your experiment?How would you report it?How would you report it?

Have Assistant verify your “Timing Report” Have Assistant verify your “Timing Report” for a cumulative experimiment. for a cumulative experimiment. In this In this experiment we used ______ timing mode with the experiment we used ______ timing mode with the stimulus to stimulus time mean of ______ and SD of stimulus to stimulus time mean of ______ and SD of ______. ______.

Please put the display into this form and raise your Please put the display into this form and raise your hand.hand. Explain what would your put in a journal. Explain what would your put in a journal.

Assistant InitialsAssistant Initials ___ ___

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Timing Exercise 2a (optional) - Run Timing Timing Exercise 2a (optional) - Run Timing Paradigm4 Paradigm4

In Cumulative Mode, Change Event, RerunIn Cumulative Mode, Change Event, Rerun

1. Open TimingParadigm4.es file (My Documents\1. Open TimingParadigm4.es file (My Documents\My Experiments\Workshop\E-Prime Exercises).My Experiments\Workshop\E-Prime Exercises).

2. Run the program with subject number 1.2. Run the program with subject number 1. 3. Change the Timing Mode on the TrialProc 3. Change the Timing Mode on the TrialProc

displays (TrialInstructions, Fixation, Probe, Mask, displays (TrialInstructions, Fixation, Probe, Mask, FeedbackDisplay1) to Event and Prereleases to “0” FeedbackDisplay1) to Event and Prereleases to “0” or or load load TimingParadgim4EventTimeNoPreRelease.es.TimingParadgim4EventTimeNoPreRelease.es.

4. Run the experiment with subject number 2. 4. Run the experiment with subject number 2.

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Plot Cumulative Time Errors Plot Cumulative Time Errors Cumulative Mode With PreReleaseCumulative Mode With PreRelease

5. Make table and graph 5. Make table and graph of TimeCumulativeError of TimeCumulativeError by Block Cumulative Run by Block Cumulative Run 1-11-1 Open Program E-DataAidOpen Program E-DataAid Open data file Open data file

TimingParadigm4-TimingParadigm4-1-1-1.1.edat edat

Click CalculateClick Calculate Move Block to rowMove Block to row Move Move

TimeCumulativeErrorTimTimeCumulativeErrorTime to Data e to Data

Click RunClick Run Click PlotClick Plot Click Excel PlotClick Excel Plot

6. Note time variation 6. Note time variation within one refresh and within one refresh and not not increasingnot not increasing

TimeCumlativeErrorTime:Mean by Block

-2.00

-1.00

0.00

1.00

2.003.00

4.00

5.00

6.00

7.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Block

Tim

eC

um

lati

veE

rro

rTim

e:M

ea

n

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Plot Cumulative Time Errors Plot Cumulative Time Errors Event Mode Without PreReleaseEvent Mode Without PreRelease

TimeCumlativeErrorTime:Mean by Block

0.00

100.00200.00

300.00

400.00

500.00600.00

700.00

800.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Block

Tim

eC

um

lati

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rro

rTim

e:M

ea

n

7. Make table and graph 7. Make table and graph of TimeCumulativeError of TimeCumulativeError by Block Evente Run 2-1by Block Evente Run 2-1 Close E-Data Aid Close E-Data Aid

WindowsWindows Open data file Open data file

TimingParadigm4-TimingParadigm4-22--1.1.edat edat

Click CalculateClick Calculate Move Block to rowMove Block to row Move Move

TimeCumulativeErrorTimTimeCumulativeErrorTime to Data e to Data

Click RunClick Run Click PlotClick Plot Click Excel PlotClick Excel Plot

8. Note time variation is 8. Note time variation is increasing with every increasing with every refreshrefresh

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Compare Results from Both Compare Results from Both ModesModes

9. Note 9. Note characteristics of characteristics of datadata Cumulative mode Cumulative mode

errors within a refresh errors within a refresh (maximum of 7ms no (maximum of 7ms no cumulative drift)cumulative drift)

Event mode increase Event mode increase by significant amount by significant amount with each event with each event causing substantial causing substantial cumulative drift (in cumulative drift (in this example an this example an average of 47 ms with average of 47 ms with a maximum of 710 a maximum of 710 ms)ms)

-2.00

-1.00

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Block

Tim

eC

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lati

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rro

rTim

e:M

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n

0.00

100.00

200.00

300.00

400.00

500.00

600.00

700.00

800.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Block

Tim

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Cumulative Mode PreReleaseCumulative Mode PreRelease

Event Mode No PreReleaseEvent Mode No PreRelease

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Timing Exercise3Timing Exercise3 1. Open My Documents\My Experiments\1. Open My Documents\My Experiments\

Workshop\E-Prime Exercises\Workshop\E-Prime Exercises\TimingParadigm5 and runTimingParadigm5 and run

2. Note Steps involved in Caching Images2. Note Steps involved in Caching Images

3. Use E-DataAid to select TargetDuration 3. Use E-DataAid to select TargetDuration and OnsetToOnsetand OnsetToOnset

4. Plot the difference between Target and 4. Plot the difference between Target and Actual TimeActual Time

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Steps to Caching ImagesSteps to Caching Images• Create CanvasCacheCreate CanvasCache

• Load CacheLoad Cache

• Display CacheDisplay Cache

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Arrange ColumnsArrange Columns 1. Open 1. Open

TimingParadigm5-3-TimingParadigm5-3-1.edat file1.edat file

2. Select Arrange 2. Select Arrange Columns tools, click Columns tools, click Remove AllRemove All

3. Select 3. Select TargetDuration and TargetDuration and OnsetToOnset, click Add OnsetToOnset, click Add and OKand OK

4. Copy two columns to 4. Copy two columns to ExcelExcel

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Chart Results in ExcelChart Results in Excel In Excel select In Excel select

both columns both columns and click on and click on Graph WizardGraph Wizard

Make line Make line chart of timechart of time

Note error Note error target versus target versus intendedintended

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View ResultsView Results Note error target versus intendedNote error target versus intended

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View ResultsView Results Determine max speed presentation Determine max speed presentation

with disk reads and caching.with disk reads and caching.

Network Server Intended and Acutal Display

0

50

100

150

200

250

1

28

55

82

10

9

13

6

16

3

19

0

21

7

24

4

27

1

29

8

32

5

35

2

37

9

Image

Mill

ise

co

nd

s

TargetDuration

OnsetToOnset

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Timing Exercise 2 Cumulative Timing Exercise 2 Cumulative TimeTime

Could you at this point?Could you at this point?

1.1. Specify when to use Cumulative Time and Specify when to use Cumulative Time and Event Time methods?Event Time methods?

2.2. Analyze the timing of a cumulative Analyze the timing of a cumulative experiment and report accurately the experiment and report accurately the timing precision in a journal article?timing precision in a journal article?

3.3. Specify the disadvantage of using Specify the disadvantage of using PreRelease and when must you be careful PreRelease and when must you be careful about it?about it?

Short Answers are included in the Exercise AppendixShort Answers are included in the Exercise Appendix

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Timing Exercise 3 Caching Timing Exercise 3 Caching QuestionsQuestions

Could you at this point?Could you at this point?

1.1. Specify the range of display times in which Specify the range of display times in which prerelease is sufficient for the computer to prerelease is sufficient for the computer to keep up and caching is not necessary?keep up and caching is not necessary?

2.2. Determine the maximal rate at which you Determine the maximal rate at which you could display images before the computer could display images before the computer can not keep up?can not keep up?

3.3. Add new images to TimingParadigm 5 to Add new images to TimingParadigm 5 to allow rapid presentation of those images?allow rapid presentation of those images?

Short Answers are included in the Exercise AppendixShort Answers are included in the Exercise Appendix