Please find the dependent and independent variable from this experiment and explain.

Vigilance is typically defined as the mental capacity to sustain attention over extended periods of time. 13 Research often operationalizes this phenomenon as the ability to detect rare and critical signals over the course of multiple periods on watch, spanning minutes 4 to several hours in duration. 5,6 Due to inherent limitations in human physical and cognitive capacities, the ability to maintain attention wanes as a function of time on task, as does performance, a phenomenon noted as the vigilance decrement function. 5 Successful vigilance performance is of vital importance to a host of operational tasks that directly impact health and safety. Real-world operational domains that necessitate observers discriminating signals from extraneous noise include civil aviation, 7 air traffic control, 8 baggage screening, 9 diagnostic medical screening, 10 nuclear power plant operation, 11 military surveillance, 12 and security operations, 13 among others. Most of the monitoring tasks inherent to these performance domains utilize dynamic displays to present information pertaining to system state. However, over the past six decades vigilance research has predominantly used static stimuli in experimental protocols designed to evoke and examine the vigilance decrement. 8,14 Such a divorce between laboratorybased simulations and real-world operational task demands can significantly hamper the validity and generalizability of vigilance research findings. 15 To address this issue, studies in recent years have attempted to build and validate a new vigilance task that employs a videogame-based protocol (Virtual Battlespace 2, VBS2). This task seeks to enhance ecological validity by presenting both signal and nonsignal stimuli in a dynamic, continuous fashion using motion with a first-person perspective. 16 To establish the task parameters of this new protocol and ensure that any changes in performance are due to the task demand of monitoring, rather than signal discrimination, the study investigated the effect of stimulus type (i.e., static versus dynamic) on detection performance using a videogame-based platform under alerted conditions. METHODS This study is framed as an improvised explosive device (IED) detection task. The videogame protocol presents a virtual environment depicting an Afghan village complete with structures, inhabitants, and domestic animals. Within these scenes were randomly placed ecologically valid signals that indicate the potential presence of an IED, such as fuel cans, trash bags, motorcycle batteries, and wooden planks sunk into the ground. The dynamic video clips and static images were excised from this VBS2 software platform and presented via Qualtrics. To determine effects of stimulus type on detection performance, the dependent variables of interest were correct detections and participants' cognitive and affective attributes, specifically task engagement, distress, worry, and global workload. Correct detections (instances where participants identified the presence of a signal when one was indeed presented) were tabulated by Qualtrics software for offline analysis. Cognitive and affective states were gauged via the administration of validated questionnaires, including the Dundee Stress State Questionnaire (DSSQ; 30-item short version 1719 ) and the NASA Task Load Index (NASA-TLX 20 ). Participants first signed an informed consent form and demographics data were collected (e.g., age, gender, previous exposure to virtual environments, videogame-playing experience). The pre-task DSSQ was then administered to assess individuals' cognitive and affective states prior to completing the task. The questionnaire was completed at this time so that difference scores (post-task scores versus pre-task scores) could later be calculated for analysis. Participants then completed a two-alternative forced-choice task (2AFCT). The experiment consisted of two counterbalanced task conditions: one composed of static pictures and one containing dynamic video clips. Each trial comprised one signal-present stimulus and one signal-absent stimulus shown sequentially. After both stimuli had been shown, participants were instructed to identify via a mouse click which stimulus included the signal. Duration was manipulated with a total of three durations: 5,3 , and 1 s stimulus presentations. The order of presentation for the trials (i.e., 10 signal-first trials, 10 nonsignal-first trials) for each duration time was randomized throughout each task condition. The task thus comprised a total of 60 trials per task condition (20 five-second trials, 20 three-second trials, and 20 one-second trials). RESULTS Twenty-nine participants were recruited to take part in this study; as they were university students, they were remunerated with extra credit for their participation. The data of three participants were excluded from the final analysis due to one incident of equipment failure, one participant with a self-reported history of simulator sickness, and one individual with a congenital color perception deficiency. Data from a total of 26 participants (15 females, 11 males) with an average age of 21.12 years was therefore analyzed. Performance outcomes were analyzed via a 2 (Stimulus Type: Static image versus dynamic clip) 2 (Task Order: Images first versus clips first) 3 (Duration: 1, 3,5 s) mixed-model ANOVA with repeated measures on the first and third factors. DSSQ difference scores and NASA-TLX workload scores were analyzed via a between-subjects (Task Order: Clips first versus images first) ANOVA. Analyses revealed a statistically significant main effect of stimulus type on detection performance (F(1,24)=25.333, p<.0001 pairwise comparisons indicated that participants made significantly fewer correct detections when the stimuli were presented via dynamic clips as opposed to static images difference="1.462,p<.0001" this main effect of stimulus type is in fig. a statistically significant for duration on detection performance was also observed p mauchly test identified violation sphericity assumption greenhouse-geisser adjusted degrees freedom are reported. revealed exhibited greater rates over compared or these shown finally there by interaction p2="0.281" both conditions same general trend decreasing decreased. however decline appears much steeper condition illustrated two-tailed t-tests conducted dssq scores minus pre-scores showed reported lower task engagement and distress result completing task. worry not affected unweighted global workload gauged nasa-tlx analyzed t-tests. analyses imposed overall average score commensurate with averages other classification cognitive tasks. current study sought determine possible statistical psychophysical equivalency visual stimuli. correctly detected critical signals equally well mean out under alerted longer versus shorter durations moreover between at yielded smallest size any collective comparisons. be considered truly distributions should gaussian. comparing across two types all three having failed reject null hypothesis equivalent conditions. designated detectable. findings import they used establish parameters subsequent effects vigilance according subjective reports stress participants. subscales t-test results profile traditional protocols: printed pm lamar university. use subject https: equivalence chapter figure performance. error bars standard errors. asterisk denotes difference. interaction. higher no worry. thus length presentation wherein most detectable indexed outcomes reports. empirical studies designed investigate extended periods time have long utilized experimental protocols exclusively present work support nature can therefore help inform refine design future intended naturalistic vigilance-type typically defined mental capacity sustain attention time. research often operationalizes phenomenon ability detect rare course multiple watch spanning minutes several hours duration. due inherent limitations human physical capacities maintain wanes function does noted decrement function. successful vital importance host operational tasks directly impact health safety. real-world domains necessitate observers discriminating from extraneous noise include civil aviation air traffic control baggage screening diagnostic medical nuclear power plant operation military surveillance security operations among others. monitoring utilize displays information pertaining system state. past six decades has predominantly evoke examine decrement. such divorce laboratorybased simulations demands hamper validity generalizability findings. address issue recent years attempted build validate new employs videogame-based protocol battlespace vbs2 seeks enhance ecological presenting signal nonsignal continuous fashion using motion first-person perspective. ensure changes demand rather than discrimination investigated platform methods framed an improvised explosive device videogame presents virtual environment depicting afghan village complete structures inhabitants domestic animals. within scenes randomly placed ecologically valid indicate potential presence ied fuel cans trash bags motorcycle batteries wooden planks sunk into ground. video excised software qualtrics. dependent variables interest affective attributes specifically workload. where one indeed tabulated qualtrics offline analysis. states administration validated questionnaires including dundee state questionnaire short version nasa load index first signed informed consent form demographics data collected age gender previous exposure environments videogame-playing experience pre-task then administered assess individuals prior completed so could later calculated two-alternative forced-choice experiment consisted counterbalanced conditions: composed pictures containing clips. each trial comprised signal-present signal-absent sequentially. after had been instructed identify mouse click which included signal. manipulated total durations: s presentations. order trials signal-first nonsignal-first randomized throughout condition. per five-second three-second one-second twenty-nine recruited take part university students remunerated extra credit their participation. excluded final analysis incident equipment failure participant self-reported history simulator sickness individual congenital color perception deficiency. females males analyzed. type: image clip order: mixed-model anova repeated measures third factors. between-subjects anova.>