PsyPad User Manual Preamble
Contents
1. then a Next button appears after each response and must be pressed before the next trial begins Time between each question Specify the mean time between response button press and the variation The next stimuli is presented after mean where 6 is sampled uniformly at random from variation variation Infinite presentation time If Yes stimuli are presented until a button is pressed otherwise if No you must specify the presentation time in milliseconds In the No case the image is replaced with the background color and the buttons remain This option can interact strangely with movie stimuli If you have chosen Yes and have a movie stimuli that is not looping you will get the background color once the movie runs out of frames If you have chosen No and a value that is shorter than the movie number of frames x frame rate 60 then the movie will be truncated Use specified seed If Yes the provided number is used to seed the random number generator handy for testing so that you get the same image se quences otherwise if No a random seed from dev urandon is used Attempt facial recognition If Yes then a picture is taken with the on board camera at the beginning of every stimulus presentation beware of the camera noise that can be turned off on the iPad Settings The image is processed to locate two eyes and a mouth The three coordinates are saved into the log file If No no2. 40 is a MOCS over three stimuli levels 16 18 and 20 using 40 trials for each level Display Configuration Background color An RGB hex string beginning with a For example FF0000 is red This is the color of the screen when the Begin button is displayed between stimuli if the Next button is used and also as the background for your images if they do not fill the entire screen or contain transparent pixels Show exit button If Yes then a small cross is displayed as per the x y width and height specifications given All measurements are in pixels and the top left of the screen is 0 0 bottom right is 1024 768 Exit button color Background and foreground colors as RGB hex strings For ex ample 00FF00 is green Ignored if Show exit button is No Button Configuration Number of buttons The number of response buttons maximum 4 Button text The text to appear on each button Background colors RGB hex string specifying the background color of each button For example 0000FF is blue Text colors RGB hex string specifying the text color of each button For example 888888 is grey Button positions For each button x y width and height All measurements are in pixels and the top left of the screen is 0 0 and the bottom right is 1024 768 even on iPad III General Test Parameters Next button after each response If Yes
3. is available to PsyPad their session information is checked against the server and if different the server version is downloaded This allows remote altering of session configurations There is no warning The server session will overwrite the iPad session Hence be careful when altering configurations on the server for existing participants 6 4 2 Automatic session transfer from iPad to Server When configurations are changed on the iPad and there is an internet connection available PsyPad will ask if you want to push the new configuration to the server If you say yes the server configurations will be overwritten so be careful 6 4 3 Log file transfer from iPad to Server This happens automatically at the end of a session if there is an internet connection and is never repeated if successful The admin user on the iPad can force the sending of all log files using Upload logs to server on the Admin Panel 7 Handling Logfiles Logfiles contain lines of text with three columns delimited by a vertical bar pipe symbol The fields are 1 time stamp in number of seconds since 1 1 1970 2 identifier that describes the line and 3 the data related to the identifier 10 Identifier Data type Meaning button_press d String The number and text on the response button that was pushed currentReversal d The number of reversals seen so far Staircase only currentStaircase d The current staircase being presented Stairca
4. on every device If exact luminance is important to you you should use a photometer and measure different pixel levels and make your images accordingly PsyPad sets the iPad to maximum brightness at the beginning of a test session but cannot control the Auto Brightness setting You should make sure this is off and instruct participants never to turn it on if luminance levels are important to your test For calibration you can create an image set that contains a set of blanks which contains full size images all of one pixel level It might be easiest to annotate each corner of the image with the pixel value too You can then set up a MOCS or staircase using this image set to aid in calibration 2 4 Ramping Images are not ramped and are presented immediately after the inter stimulus interval expires If you want to ramp your stimuli on and or off make a movie style image that contains the ramp you require 2 5 Timing We do not have program access to the graphics clock on the iPad and so very precise frame presentation times are not supported If you require very fine timing control of stimuli presentations then PsyPad is probably not for you We have endeavoured to be as accurate as possible with presentation and inter stimulus interval timing and it should be sufficiently accurate for most tests 2 6 Uploading the images Once you have all the images you need for a single test named correctly you should zip them a
5. picture is taken and nothing is logged After choosing all of your settings don t forget to select the Save Configuration button 4 1 MOCS To set up a MOCS procedure you need the stimuli levels to test and the number of trials per level Once you have chosen your image set to use as the basis for your test the levels are defined by the folder names in your image set For example if you used the image set from Figure 2 b the test levels are low med and high On the server the number of trials per level to use is specified in a comma separated list as Lli ni 2 N2 where 4 is the stimulus level matching the folder names n is the number of trials at that level On the iPad the interface for specifying these is a bit nicer as it lists all available levels and you enter the number of trials next to each level leave blank for no trials Remember if you alter tests on the iPad to upload them to the server before a participant logs in otherwise the server version will overwrite your changes if an internet connection is present For the example in Figure 2 c if you want 10 trials per level you would use the following string low 10 med 10 high 10 The order of levels is chosen at random and images within each level are chosen at random without replace ment unless the number of trials exceeds the number of images in which case some images will be repeated images trials times 4 2 Stair
6. then this test is part of a participants practice session if also Enabled Order This specifies the order in which this test will appear in the session if enabled Any integer is fine the tests are sorted by this number to get their order for a session Day of week If enabled this test configuration will only be used on the selected days of the week Image Parameters Image Sequence Choose from the images in the image library Created as in Sec tion 2 Loop animated images Only for images that are a sequence of frames movie If true then the frames loop until a button is pressed Animation frame rate This is the number of frame refreshes on the iPad for which each image in the movie sequence should be displayed Currently iPads have a frame rate of 60Hz For example if you want a movie of 8 images to display for 400 ms you would enter 3 here 3 60 x 8 0 4 Staircase Method Parameters Use staircase If Yes then staircase is used otherwise MOCS Number of staircases The number of staircases you wish to interleave should be at least one Start level A list of start levels separated by a character one for each staircase each must match a filename of an image as per Section 2 Number of reversals A list of the number of reversals before terminating the staircase separated by a character one for each staircase Floor or ceiling hits to finis
7. 1066 44ms 0 232 52 18 899 61ms a 101 79 2 3 52 870 92ms a 45 82 60 895 82ms 75 36 a b Correct Per Level Current Log Staircase 1 Reversals 100 00 o 2 j i gt 42 80 00 Staircase 2 16 1 18 83 33 20 100 00 28 100 00 100 00 9 v 8 i 44 00 00 52 100 00 60 100 00 A 8 ie ww o a Figure 5 Overall structure of data in PsyPad An administrator owns an image library and a list participants Each entry in the image library is a zip file of images as per Section 2 Each participant has a list of test configurations named Tests in this figure see Section 4 and log files of previous tests Section 7 Each test configuration uses one of the image sets in the library The group of enabled test configurations for each participant make up a session 14
8. PsyPad User Manual Preamble This guide assumes you already know how to set up a visual psychophysics experiment For example you know the difference between MOCS and a staircase and you know about gamma correction If not find a translator who speaks psycho babble or perhaps PsyPad is not the tool for you Throughout we refer to a test as a sequence of stimuli either MOCS single or multiple staircases resulting in reversals or collection of correct results A collection of tests performed in sequence make up a session Document History The initial draft of this manual was written by Andrew Turpin David Lawson and Allison McKendrick in August 2013 Contact aturpin unimelb edu au for more information 21 March 2014 Added citation to Journal of Vision Paper Citation Please cite the following if you use PsyPad in your research PsyPad A platform for visual psychophysics on the iPad Andrew Turpin David J Lawson and Allison M McKendrick J Vis March 11 2014 14 3 16 doi 10 1167 14 3 16 as Bibtex article Turpin11032014 author Turpin Andrew and Lawson David J and McKendrick Allison M title PsyPad A platform for visual psychophysics on the iPad volume 14 number 3 year 2014 doi 10 1167 14 3 16 URL f http www journalofvision org content 14 3 16 abstract eprint http www journalofvision org content 14 3 16 full pdfthtml journal Journal of Vision Contents 1 Befor
9. ages that are presented centred on the screen Dynamic stimuli are a sequence of frames that are also PNG images The filenames of the images must be in a specific format see Section 2 If you cannot precompute all the stimuli you might need in a test then PsyPad will not work for you 5 Buttons What response buttons do you need for your test Up to four rectangular buttons are allowed Where should they be placed on the screen What color width and height should they be 6 Thresholding strategy MOCS or staircase If you choose a MOCS you must decide on the stimuli levels you want to test and how many trials per level see Section 4 1 For staircases you must decide how many to interleave and for each the starting values the number of reversals and the step sizes between each reversal See Section 4 2 for more information 7 How many tests in a session Does a session from participant login on the iPad to completion of all tests consist of just one test a thresholding run for one stimuli type or do you want more than one test in a session What order do you want the tests Do you want different tests on different days of the week Do you want a different random seed for each test See Section 5 for information on how to set up tests 8 Do you want a practice session If you mark some test configurations as Practice configurations then once a participant logs in to PsyPad there are options to Begin Test and Begin Prac
10. case A correct response as determined by matching the first character of the filename of the stimulus with the button number pressed will cause the current step size to be subtracted from the current stimulus level to determine the next stimulus level to display An incorrect response will cause the current step size to be added to the current stimulus level A reversal is registered whenever the number of wrong correct in a row is recorded followed by the number of correct wrong in a row For example in a 1 up 1 down staircase wrong 1 correct 1 a correct followed by an incorrect or vice versa is a reversal In a 1 up 2 down staircase 4wrong 1 correct 2 then reversals would be triggered by responses incorrect correct correct and correct correct incorrect Each staircase terminates when its number of reversals is achieved or if the count of minimum maximum stimulus value correct incorrect reaches the specified number 4 3 Managing Test Configurations When you select an existing test configuration there is an option to Copy Configuration at the top of the screen If you choose a participant and a configuration from the drop down list and select Copy Configuration then the current configuration will be copied to that participant Note that each participant has New Configuration as an option in the drop down list and if chosen then the current configuration is added to the participants list of configurations Be careful that the Orde
11. e starting 2 2 Image Stimuli 3 Z1 pingle frame images 4 te Gir le bd oe eee Si ee Ge Ge ie WE ae ae A 5 2 2 Multiframe images movies oaao 5 2 3 Gamma correction and Auto brightness ooa ee 5 24 Rampihg neu 2 ie eb ma aes ae ee ES l ee ee A E EE e a a i 5 29r MAMI Gs ne to oe ar ree ta aaa uy GMA We Bnd Bue Dae ies dood oh te at rn e BM ee WR Bd 5 2 6 Uploading the images 5 660 ecg be ha ee ee eee ee Bre Sew we eB 5 3 Adding Participants 6 3 1 On GhestPad s 2 oe ee Bp Se ne BE SA Bid QP ae ae nee SOG lnc be ae ae 4 6 225 CORA HE DeVere x sete a be elas Oe ait ee oA le Be ale Gert nee ae ree tes ete Aao dA 6 4 Test Setup 6 AA MOCGS 85 and 2S ae ed Se Pk boa Ba del AE ee a a ee ee 2D 8 ALD SUAIECASC 3 te fs Borer ts th oh ae eve BO HR Bla ee Re ke ae ce etn be A BO Be BA 8 4 3 Managing Test Configurations 2 4 5 24 00 648 dod ee ee ee ee e i a daa 9 5 Session Configurations 9 6 Server Setup 9 6 1 The PsyPadnetiaw Server d anre Rad A we A ee es Be aed 9 6 2 Your OWD Server i cc Se ine bee pee eke Gey bod Re ee See Aad Be Re SG 9 6 3 Configuring on the iPad em eny Ed a a ee a Pe ELA Oe ee 9 6 4 Communication with iPad 2 2 0 0 00 2 o e a Da a a a a a e a e a a 10 6 4 1 Automatic session transfer from Server to iPad ooa a 10 6 4 2 Automatic session transfer from iPad to Server ooa 0000 2b 10 6 4 3 Log file transfer from iPad to Server 2 ee ee 10 7 Handling Logfiles 10 8 Checking test r
12. ersal null 1378869891 next_question 16 1378869891 currentStaircase 0 1378869891 currentReversal 5 1378869891 presented_image 52 1_002 png 1378869891 presented_buttons Concentric Radial 1378869891 image_hidden null 1378869892 reaction_time 1424 79ms 1378869892 button_press 1 Concentric 1378869893 next_question 17 1378869893 currentStaircase 0 1378869893 currentReversal 5 1378869893 presented_image 52 1_001 png 1378869893 presented_buttons Concentric Radial 1378869893 image_hidden null 1378869895 reaction_time 1773 27ms 1378869895 button_press 2 Radial 1378869895 reversal null 1378869895 test_finished null 1378869895 exit_test null Figure 4 An example logfile for a staircase procedure right and a summary of that logfile left 13 aa Logs Current Log peaa Current Log Reaction Time Analysis Reaction Time Correct Per Level Reversals Presentations Per Level test begin next_question 1 gt gt 30 09 2013 8 20 49 PM exit_button_x 950 button2_y 700 num_buttons 2 staircase_max 30 09 2013 8 20 49 PM currentStaircase 4 currentReversal o presented_image 60 1_7 sanamini adian 30 09 2013 8 20 49 PM 30 09 2013 8 20 49 PM 30 09 2013 8 20 49 PM naninarnnaa 2 00 00 DAA o 953 11ms o 0 00 2 AE 838 96ms 0 64 05 6 865 24ms o 50 78 a 8 859 10ms 0 66 44 12 778 91ms o 60 47 a
13. esults on the iPad 11 9 iPad Settings 11 10 Upcoming features 12 1 Before starting Before you begin you will need to make some decisions about your setup and experimental design 1 Server location In order to send images for stimuli to the PsyPad app and to get test log files off the iPad running PsyPad a server is required We provide psypad unimelb edu au for your use but perhaps you want to run your own not recommended or supported See Section 6 discusses the server in more detail 2 Your administrator login name All test configurations images and participants are attached to your administrator login on the server see Figure 1 Choose one and create a password You will need to contact us to be added to psypad unimelb edu au 3 Participant login names PsyPad requires participants to login to their iPads before each session so that their results can be tagged with their login in the log files These login names will be sent to the server and stored in log files in unencrypted text so should not contain any information that might breach the privacy of participants or ethics of your experiment Also as they must be entered by the participants before each test you might like to make them easy to type on the iPad for example all letters or all numbers and not a mix of the two See Section 3 for more information on how to create logins for participants 4 Stimuli All stimuli in PsyPad are precomputed 24 or 32 bit PNG im
14. et connection is present the configuration from the server will overwrite any configuration on the iPad 3 2 On the Server Choose Participants and Add participant at the bottom of the participant list Each participant is given a copy of Default Participant s session which you can edit Altering a session involves altering the individual test configurations as per Section 4 You may also copy participant s configurations and then alter those using the Copy Configuration pull down menu and button See Section 4 3 4 Test Setup In order to define a test you need to choose an image set already loaded via the server see Section 2 and then choose several options as described in this table This table lists the options in the order they appear on the server interface The same options are available on the iPad Note that to reorder tests in a session on the iPad you tap the Reorder button in the top right of a particpant s screen when logged in as admin which allows you to drag the tests into the order you want and then tap Done General Settings Configuration Name Simply identifies the test configuration This text appears on the iPad along with a Begin button before the test You might like to put something here that reminds the participant of the task Does not have to be unique but might be easier for you if it is Enabled If true then this test is part of a participants session Practice Configuration If true
15. h A list of the number of times the minimum maximum stimuli are shown before terminating the staircase separated by a character one for each staircase Minimum level The minimum stimulus level separated by a character one for each staircase each must match a filename of an image as per Section 2 Maximum level The maximum stimulus level separated by a character one for each staircase each must match a filename of an image as per Section 2 A values The step sizes before each reversal as a comma separated list sep arated by a character one for each staircase must be the same number as in Number of reversals for each staircase wrong to get easier The number of incorrect responses before the stimulus level is increased separated by a character one for each staircase Note that an incorrect response adds the current step size to the current stimuli level correct to get harder The number of correct responses before the stimulus level is reduced separated by a character one for each staircase Note that a correct response subtracts the current step size from the current stimuli level MOCS Parameters questions per level A comma separated list of pairs of the form s n where s is the stimulus level matching the filename of an image in the chosen image set and n is the number of trials For example 16 40 18 40 20
16. ifications You probably want to make sure Do Not Disturb mode is active and that you are receiving FaceTime calls from No One and that Repeated Calls are off FaceTime Turn it off 10 Upcoming features e Start screen to appear with begin button before each test e Blocking of MOCS trials to ensure no two of the same level in a row e Interactive Screen preview during test configuration in the server e Auto emailing of log files from server nominated email addresses 12 Summary Test date 11 9 2013 13 24 11 Glass stairc Practice no Staircase 0 Not seen Seen min Reversal Reversal Reversal Reversal Reversal Reversal Start time 11 9 2013 13 24 11 11 9 2013 13 24 55 O minutes 44 seconds End time Duration ase max oOoPRPWNEF 6 58 54 58 52 54 52 1378869851 test_begin 1378869851 next_question 1 1378869851 currentStaircase 0 1378869851 currentReversal 0 1378869851 presented_image 50 2_005 png 1378869851 presented_buttons Concentric Radial 1378869852 image_hidden null 1378869859 reaction_time 7711 23ms 1378869859 button_press 1 Concentric 1378869860 next_question 2 1378869860 currentStaircase 0 1378869860 currentReversal 0 1378869860 presented_image 58 2_003 png 1378869860 presented_buttons Concentric Radial 1378869860 image_hidden null 1378869861 reaction_time 1820 66ms 1378869861 button_press 2 Radial 1378869890 rev
17. igure 2 a for an example The button numbers are used to generate a test summary on the iPad for the admin user see Section 8 and to determine correctness for each step in staircase procedures If you do not follow this naming convention staircases will not work and on iPad analysis will not work While folder names in the format for a staircase also match the requirements for a MOCS the folder names for a MOCS can be more general for example as in Figure 2 b 2 2 Multiframe images movies Dynamic stimuli are achieved using a sequence of frames that are also 24 bit RGB PNG images or 32 bit RGBA but in a subfolder named as for the single images without the png suffix with the individual frames named in lexicographic order for example 11 comes before 2 If you want numeric order make sure you pad with leading zeroes as in Figure 2 c which shows stimulus level 48 consisting of 11 frames where a button press of 1 would be correct The time that each frame of the movie is displayed before the next frame is presented and the looping behaviour is set as part of the test configuration see Section 4 2 3 Gamma correction and Auto brightness There is no Gamma correction or look up table LUT capabilities in PsyPad You need to do your own gamma correction and luminance determination offline and then choose the pixel values in your images accordingly For example there is no guarantee that RGB 127 127 127 is mean luminance
18. ilenames are important PsyPad will also faithfully display 32 bit RGBA PNG images if you want to make use of the Alpha channel for transparency The thresholding algorithms in PsyPad identify stimuli using folder names not image filenames This allows for different random images of the same stimulus level to be used by PsyPad For example when PsyPad is asked to present a stimulus of level 33 it randomly selects an image from the folder named 33 Each stimuli folder must be named in the correct format for the thresholding algorithm that you chose e any alphanumeric text if a MOCS is to be used or e an integer corresponding to stimulus level if a staircase thresholding algorithm is to be used Note that because PsyPad s staircases work on integer stimuli levels you may have to be a little creative in mapping your thresholding domain onto an integer domain For example if you are thresholding in log units with a step size of 0 2 log units you might convert a stimulus level to the integer 1000 x 10 giving stimuli levels of 6 10 15 25 39 63 100 158 251 398 630 1000 Inside each folder the images themselves must be named in a specific format as follows Administrator ici dmi a ato Participants Login Default Test Test Test Figure 1 Overall structure of data in PsyPad An administrator owns an image library and a list of participants Each entry in the image library is a zip file of images as per Secti
19. ll into a single zipfile without an enclosing folder using zip on MacOS or Linux or winzip on Windows and upload them to the server using the Images menu options They will then be automatically processed on the server and put in a suitable format a single big file with an index for transfer to the PsyPad app on the iPad When PsyPad is next started with an internet connection to the server and a participant logs in the images will be transferred and stored on the iPad This might take a while so it is recommended that you log in as at least one participant that uses the image set so that this upload is already done before the actual participants uses the app 3 Adding Participants There is one participant already existing in the system called Default Participant which you can configure to have versions of your tests This participant is copied whenever a new participant is added either on the iPad or on the Server 3 1 On the iPad Log in as admin and choose Add Participant The new participant will be given a copy of the Default Partic ipant s configurations which you can then edit You can only use image sets that are already on the iPad for other participants if you add users on the iPad WARNING if you want the participant and their configurations to persist after the participant logs in you should Upload the participant to the server before they log in Recall that when the participant first logs in and if an intern
20. on 2 Each participant has a list of test configurations named Tests in this figure see Section 4 and log files of previous tests Section 7 Each test configuration uses one of the image sets in the library The group of enabled test configurations for each participant make up a session 1_01 png 1_02 png 2_00 png 2_01 png igiie iieaie O 1_01 png 1_02 png 2_00 png 2_01 png 1_01 png 1 02 png 2_00 png 2_01 png aip ii A a fre a fre 2 ire 5 1 01 png 1_02 png 2_00 png 2_01 png 1 01 png 1_02 png 2_00 png 2_01 png d 1 01 png 1 02 png 2_00 png 2_01 png a b 1 01 png 1 02 png 2_00 png 2_01 png PRP y PPPE g Pwe 3 ee GA Figure 2 Folder and image filenames for a a staircase or MOCS procedure that has stimuli levels 0 5 10 15 b a MOCS with three levels low med and high and c a movie stimulus with levels 39 42 54 In a and b the prefix of the filenames give the button number for a correct response 1 or 2 and c the same is given by the prefix of the subfolder name In c files are movie frames that are presented in lexicographic sequence 2 1 Single frame images Within the folder individual images must be named as b_n png where b is the button number that would correspond to a correct response for this stimuli and n is an integer See F
21. r fields end up correct in the target participant There is also a Delete button at the top of each configuration which deletes the current test configuration from the current participant as listed at the top of the screen Remember you can always set Enabled to Off rather than deleting 5 Session Configurations A session is simply a list of enabled tests which are executed in order If you want different tests on different days of the week you should make sure that all the tests for all days are enabled and then each test is configured for the appropriate day Note that the practice session is separate from the test session and so if you want the same test to appear in both you need to take a copy and select the Is practice configuration in one of the copies 6 Server Setup 6 1 The PsyPad net au Server Disclaimers Note that while psypad net au is password protected and under normal circumstances your log files are not available to any other users we are not providing a state of the art secure environment Any determined hacker will be able to get access to your logs in much the same way as they can access your personal computer iPad etc despite our best efforts We also have administrator access to your logfiles While we have procedures in place to limit the use of this access we may inadvertently view your logs while maintaining or updating the system As such do not include any private or unethical data in your participan
22. s the four choices and the actual log file for a participant s test which can be reached by logging in as admin tapping the participant s login name View Logs and then the log in which you are interested The choices reveal the following Reaction Time shows a bar graph of the mean reaction time for each of the stimuli levels shown in the test The mean is in text in the bar and the standard deviation of each reaction time is show in parentheses as o For example Figure 5 b Correct Per Level shows a bar graph of the correct for each of the stimuli levels shown in the test For example Figure 5 c Reversals shows a bar graph of the stimulus level at each reversal for staircase procedures For example Figure 5 d Presentations Per Level shows a bar graph of the number of times each stimulus level was presented in the test 9 iPad Settings There are several settings on the iPad that are not controlled by PsyPad Auto Brightness If contrast is important to your experiment you have to turn this off manually PsyPad sets the brightness to maximum at the beginning of each session Sounds You may like to set the Ringer and Alerts volume to 0 so that there is not a sound when PsyPad uses the camera 11 Wi Fi Obviously if you want participant sessions pulled from the server to the iPad or want logfiles to upload you need to configure the Wi Fi connection so that the iPad is connected to the internet Not
23. se only exit_test 5 Last line in a single test log image_hidden Time image was replaced with background next_question d The question number in the current test Staircase only next_question d d The question number in the current test numerator and the total number of questions denominator MOCS only presented_buttons String Labels of each button presented for this question presented_image String Filename of image that was presented at this time reaction_time d ddms Time between image presentation and button push reversal 7 This response caused a reversal Staircase only test_begin String Description of all test parameters in JSON format test_finished 7 Time the test finished distance_detection String Result of face detection if turned on An example string is Question 5 Detected facial features left eye 733 75 443 75 right eye 932 50 482 50 mouth 876 25 236 25 where each number pair is the x y coordi nate of the preceeding feature Table 2 An example logfile for a staircase procedure right and a summary of that logfile left d indicates an integer and d dd indicates a decimal number Figure 4 shows an example log file for a staircase procedure and Table 2 describes each identifier The log file format has been designed for processing with script languages such as awk Perl Python and so on The psypad net au server offers the summary text 8 Checking test results on the iPad Figure 5 a show
24. t identifiers or image file names that will appear in the log files Note that this standard level of security does not compromise your research as log files only contain sequences of image names and button responses There is no easy way for an outside observer to tell what the stimuli are or to which images filenames correspond While the server is currently backed up weekly do not rely on this for your data persistence Make your own backups of log files using the Export all logs regularly 6 2 Your Own Server The source code for the server is available upon request but we do not plan to support you in running your own server 6 3 Configuring on the iPad As shown in Figure 3 logging in as admin on the PsyPad app default password banana gives you options to alter the password the server location and the username and password for the server account You need to configure the server here before you can download any images participants and so on Admin Panel pt4 Download pt5 Download Load server participant list Upload logs to server Download all participants from server excl logs Upload all participants to server excl logs Admin Password eececcee Server URL http www psypad net au Username alice Password eoecccce Figure 3 The Admin Panel as it appears on the iPad using PsyPad 6 4 Communication with iPad 6 4 1 Automatic session transfer from Server to iPad When a user logs on and an internet connection
25. tice Test The practice test session can be configured separately from the main test session but otherwise shares all features with main test sessions Practice sessions are identifiable as such in log files 9 Internet connection All tests undertaken by participants are logged If there is an internet connection present at the end of a session and the target server is configured correctly then the log file for that session will be sent to the server You can also log in as admin on the iPad at a later date and send all logfiles for all participants to the server See Section 7 for more information on uploading logs If an internet connection is present when a participant logs in to PsyPad their session configurations are downloaded from the server If there are new configurations in the download that use images sets that are not already on the iPad these too are downloaded This allows remote altering of participants testing parameters without having to use their iPad Beware that this will overwrite any unsaved changes made to configurations on the iPad See Section 6 for details on remote management of participants and session configurations 2 Image Stimuli All stimuli in PsyPad are 24 bit RGB PNG images www libpng org pub png which are presented without alteration in the centre of the screen You can generate these any way you like ImageMagick Photoshop Matlab R custom C code etc but their folder directory location and f
Download Pdf Manuals
Related Search