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1.
Abstract

The purpose of this study was to construct and evaluate a criterion-referenced test for archery at the beginning level. Subjects shot a total of 24 arrows from a distance of 20 yards (18.3m). Each arrow was considered a trial, and scored as 0 for an arrow score of 1 or 3, and as 1 for an arrow score of 5 or higher. Specific techniques for estimating validity and reliability in a criterion-referenced framework were applied to the data, and Berk's (1976) method was utilized in establishing an optimal cut score. The activity was sensitive to instruction, and the techniques applied to the data functioned well. The validity estimate was .73; the reliability estimates were k =.73 and P = .87. Based on the second 12 arrows, subjects who scored a 5 or greater were designated masters, and those scoring 4 or less were designated nonmasters. This cutoff score was used in the derivation of the reliability and validity estimates. Berk's method proved very useful in establishing a valid and reliable cutoff, and misclassifications were, to a great extent, minimized.  相似文献   

2.
Abstract

This paper discusses the use of generalizability theory, a flexible intraclass approach, for estimating the reliability of a motor performance task. The generalizability technique provides variance component estimates for each factor of an analysis of variance design. These variance estimates can be utilized to define a number of reliability coefficients which are dependent upon the logical or theoretical rationale for assigning variance component estimates as true score or error score variance. The second section of this paper presents a study illustrating the use of generalizability theory in estimating the reliability of a motor performance task. The purpose of this study was to determine the reliability of first-ball scores for beginning college bowlers. The facets of the generalizability study were identified as sex of the bowler, trials, and days. Three reliability coefficients, R 1 (.93), R 2 (.92), and R 3 (.84), were computed by assigning the different factors to either true score or error score variance. The performance of beginning college bowlers as measured by first-ball scores is reliable. While the information might be useful for the teacher or researcher who is interested in detecting between-subject differences in coeducational bowling classes, the primary purpose of this paper was to demonstrate the use of generalizability theory to estimate reliability coefficients for a set of motor performance test scores.  相似文献   

3.
Abstract

Independent estimates of the errors of measurement and the intra-individual variations have been made for arm strength (Smedley dynamometer) and vertical jumping (Henry apparatus). The intra-individual variations are much larger than the measurement errors; thus they constitute the chief factor that determines test-retest reliability in these two physical performances. The tolerable error for measuring strength is ± 0.82 kg.; for jumping it is ± 0.5 in. In order to avoid loss of accuracy, it is necessary to read the dial or scale with approximately twice this precision. The method of computing test-retest reliability as the ratio of “true score” variance to total variance is found to underestimate the coefficient when the variability of test and retest scores differs by more than 15 percent. A formula for correcting this attenuation is presented.  相似文献   

4.
Abstract

The purpose of this study was to examine procedures for estimating the reliability for a criterion-referenced measure in the psychomotor domain. Reliability is defined as the consistency of classification of examinees into mastery and nonmastery categories. Three trial mastery criteria—6, 7, 8—were utilized along with three test mastery criteria—.6n, .7n, .8n. Motor skill was defined as first-ball scores of each frame in a line of bowling. Since the empirical distribution functions for men and women subjects were significantly different at trial criteria of 6 and 7, separate reliability coefficients were estimated for each sex. The single administration estimates of reliability developed by Huynh and Subkoviak were equally good indicators of the Swaminathan-Hambleton-Algina estimate of P when the test was administered on 2 days (P represents the proportion of agreement of classifications). Variations in trial and test mastery criteria yielded different proportions of subjects assigned to mastery and nonmastery classifications. When the proportion in either category was high, P tended to be high. As the proportions in the two categories became more similar, the values of P tended to drop. In general, increasing the number of trials was paralleled by an increase in P.  相似文献   

5.
Abstract

The aims of this study were to: (1) assess the reliability of various kinetic and temporal variables for unilateral vertical, horizontal, and lateral countermovement jumps; (2) determine whether there are differences in vertical ground reaction force production between the three types of jumps; (3) quantify the magnitude of asymmetry between limbs for variables that were established as reliable in a healthy population and whether asymmetries were consistent across jumps of different direction; and (4) establish the best kinetic predictor(s) of jump performance in the vertical, horizontal, and lateral planes of motion. Thirty team sport athletes performed three trials of the various countermovement jumps on both legs on two separate occasions. Eccentric and concentric peak force and concentric peak power were the only variables with acceptable reliability (coefficient of variation = 3.3–15.1%; intra-class correlation coefficient = 0.70–0.96). Eccentric and concentric peak vertical ground reaction force (14–16%) and concentric peak power (45–51%) were significantly (P < 0.01) greater in the vertical countermovement jump than in the horizontal countermovement jump and lateral countermovement jump, but no significant difference was found between the latter two jumps. No significant leg asymmetries (–2.1% to 9.3%) were found in any of the kinetic variables but significant differences were observed in jump height and distance. The best single predictors of vertical countermovement jump, horizontal countermovement jump, and lateral countermovement jump performance were concentric peak vertical power/body weight (79%), horizontal concentric peak power/body weight (42.6%), and eccentric peak vertical ground reaction force/body weight (14.9%) respectively. These findings are discussed in relation to monitoring and developing direction-specific jump performance.  相似文献   

6.
PurposeThe purpose of this study was to examine the reliability and the learning effect of an isokinetic trunk flexion–extension protocol designed to simultaneously assess trunk muscle strength and endurance. In addition, the effect of the participants' sex on the reliability data was examined.MethodsFifty-seven healthy and physically active young men (n = 28) and women (n = 29) performed the isokinetic protocol 5 times, separated by a week between each of the first 4 sessions and by a month between the last 2 sessions. The protocol consisted of performing 4 trials of 15 maximum flexion–extension concentric exertions at 120°/s (range of trunk motion = 50°). The absolute and relative peak torque and total work were calculated to assess trunk flexion and extension strength. In addition, endurance ratio, modified endurance ratio, fatigue final ratio, recovery ratio, and modified recovery ratio variables were used for the assessment of trunk muscle endurance in both directions.ResultsRegarding the absolute reliability, no relevant changes were found between paired-comparison sessions for most strength and endurance variables, except for total work and relative total work variables in the flexion movement in both sexes. In addition, the typical error of the isokinetic variables was lower than 10% in both males and females, and minimum detectable changes ranged from 7% to 20%, with a tendency to be higher in females and in endurance variables. The strength variables showed high-to-excellent intraclass correlation coefficients (ICCs; >0.74); however, for the endurance variables only the endurance ratio and the modified endurance ratio obtained moderate-to-high ICC values (0.57 < ICC < 0.82). In addition, the analysis of the variance reported no significant differences between consecutive pairs of sessions for most variables in both sexes.ConclusionOverall, these findings provide clinicians, trainers, and researchers with a 10-min single-session protocol to perform a reliable muscle strength and endurance evaluation of trunk flexor and extensor muscles, all within the same protocol.  相似文献   

7.
Abstract

An analysis system for barbell weightlifting exercises is proposed to record reliable performance and neuromuscular responses. The system consists of surface electromyography (sEMG) synchronized with electrogoniometry and a barbell position transducer. The purpose of this study was to establish the reliability of the three components of the system. Nine males (age 28.9 ± 4.8 years, mass 85.7 ± 15.1 kg) performed squat exercise at three loads on three separate trial days. A data acquisition and software system processed maximal knee angle (flexion), mean power for the concentric phase of squat exercise, and normalized root mean square of the vastus lateralis. Inter-trial coefficients of variation for each variable were calculated as 5.3%, 7.8%, and 7.5% respectively. In addition, knee joint motion and barbell displacement were significantly related to each other (bar displacement (m) = 1.39–0.0057 × knee angle (degress), with goodness-of-fit value, r 2 = 0.817), suggesting knee goniometry alone can represent the kinematics of a multi-joint squat exercise. The proven reliability of the three components of this system allows for real-time monitoring of resistance exercise using the preferred training methods of athletes, which could be valuable in the understanding of the neuromuscular response of elite strength training methods.  相似文献   

8.
Abstract

The published data on the reliability of self report measures of physical activity most commonly used in the cardiovascular disease epidemiology literature revealed high test-retest reliability coefficients for two of the measures, and modest to nonexistent intertest correlations. Validity coefficients were low to modest. The published data on the accuracy of the self report measures, however, revealed memory decay, memory of rare events alone, and lack of motivation in memory recall. An information processing model, composed of encoding, storage, and retrieval processes is proposed to understand the memory of physical activity, and to identify necessary skills for accurate self report identified at each step in the process. Questions requiring further research to specify this model and, in turn, improve accuracy of recall, are raised.  相似文献   

9.
Errata     
Abstract

One hundred and eighteen national collegiate fencers engaged in the first round competition in the 28th annual NCAA Fencing Championships held at the University of Illinois, Chicago Circle Campus. After the first day of competition, the field size was reduced to 72 fencers or 24 fencers per weapon. Through the use of a unique scoring device, response times and accuracy measurements were recorded for each fencer. The fencers then engaged in their respective round robin tournament according to class of weapon; epee, sabre, or foil. Two criterion measures of fencing success were then correlated with response times and accuracies. Correlation coefficients for sabre fencemen were slightly better than 0. Criterion measures for epee fencers showed a low relationship with response time and accuracies while those of foil showed a slight to fair relationship.  相似文献   

10.
Abstract

The location and outcome of all free kicks taken directly at goal in the 2007 women's football World Cup were assessed to identify areas with the most goal-scoring potential and assist with tactical decisions and training design. Video of all free kicks taken directly at goal in the 32 games was captured and the location of the ball on the pitch was calculated from pitch markings and image pixel coordinates using a customized curve-fitting method. The outcome of each free kick was determined and for those that resulted in a goal or were saved, information on ball flight time and the placement of the ball relative to the goal was reported. All seven free kicks that resulted in a goal were taken from a central area within 7 m of the penalty circle, placed at the edge of the goal within approximately 1 m of the goalpost, and had an average flight time of 1.09 s, which was significantly faster than for those that were saved. All free kicks directed towards the bottom and centre of the goal resulted in straightforward saves for the goalkeeper. It is recommended that teams should consider a direct shot from free kicks awarded within 7 m of the penalty circle. For free kicks from wide areas and areas further from the goal, players should be aware of their individual ability and only take a shot when they perceive the probability of scoring a goal to be high. Otherwise, alternative attacking strategies should be considered to avoid an easy turnover of possession.  相似文献   

11.
Abstract

Through computer simulation of data this study explored the effectiveness of various estimators of reliability in the context of trials-to-criterion testing. The estimation procedures employed were coefficient alpha, parallel forms, and an estimator, called UEV (unbiased error variance), based on estimates of error variance. Based on the results of the computer simulation, the UEV estimator was recommended as the procedure to employ when a single administration of a trials-to-criterion test is planned. However, if a second test administration is feasible the parallel forms estimator was recommended for estimating the reliability of a trials-to-criterion test.  相似文献   

12.
Abstract

Current studies have reported high accuracy in global positioning system (GPS) and recently developed ultra-wideband (UWB)-based tracking systems for monitoring time – motion patterns. The accuracy and reliability of both systems may be different in tactical analysis application, an aspect that has never been studied previously. The aims of the present study were: (i) to determine and compare the accuracy of GPS and UWB technologies in soccer players’ positions (ii) to compare the tactical application of both systems. Following institutional ethical approval and familiarisation, 14 well-trained soccer players performed tests around five courses: (a) field perimeter, (b) halfway line, (c) centre circle, (d) perimeter of the penalty area, and (e) semicircle penalty area. Also, a small-sided game was played monitored with WIMUPRO? to determine real and practical differences in accuracy of both systems in tactical analysis. For the GPS, the mean absolute error (N?=?9445) of “x” and “y” coordinates was 41.23?±?17.31?cm and 47.6?±?8.97?cm, respectively. For UWB, it was 9.57?±?2.66 cm and 7.15?±?2.62 cm. The results of the “x” and “y” accuracy comparison were significantly lower in all cases (p?<?0.05) with an ES of 0.78 and 0.95, respectively. In a real practical application, the differences of both systems reached 8.31% in typical tactical variables (ES?=?0.11). In contrast to GPS-10Hz, UWB WIMUPRO?-20?Hz has been demonstrated to be an acceptable technology to estimate the position of players on the pitch with high accuracy and be a useful, automatic, and portable instrument for tactical analysis measurement.  相似文献   

13.
Abstract

This study analysed the effect of imposing a pause between the eccentric and concentric phases on the biological within-subject variation of velocity- and power–load isoinertial assessments. Seventeen resistance-trained athletes undertook a progressive loading test in the bench press (BP) and squat (SQ) exercises. Two trials at each load up to the one-repetition maximum (1RM) were performed using 2 techniques executed in random order: with (stop) and without (standard) a 2-s pause between the eccentric and concentric phases of each repetition. The stop technique resulted in a significantly lower coefficient of variation for the whole load–velocity relationship compared to the standard one, in both BP (2.9% vs. 4.1%; P = 0.02) and SQ (2.9% vs. 3.9%; P = 0.01). Test–retest intraclass correlation coefficients (ICCs) were r = 0.61–0.98 for the standard and r = 0.76–0.98 for the stop technique. Bland–Altman analysis showed that the error associated with the standard technique was 37.9% (BP) and 57.5% higher (SQ) than that associated with the stop technique. The biological within-subject variation is significantly reduced when a pause is imposed between the eccentric and concentric phases. Other relevant variables associated to the load–velocity and load–power relationships such as the contribution of the propulsive phase and the load that maximises power output remained basically unchanged.  相似文献   

14.
Abstract

The primary aim of this study was to develop and validate a golf-specific approach-iron test for use with elite and high-level amateur golfers. Elite (n=26) and high-level amateur (n=23) golfers were recruited for this study. The ‘Approach-Iron Skill Test’ requires players to hit a total of 27 shots. Specifically, three shots are hit at each of nine targets on a specially constructed driving range in a randomised order. A real-time launch monitor positioned behind the player, measured the carry distance for each of these shots. A scoring system was developed based on the percentage error index of each shot, meaning that 81 points was the maximum score possible (with a maximum of three points per shot). Two rounds of the test were performed. For both rounds of the test, elite-level golfers scored significantly higher than their high-level amateur counterparts (56.3±5.6 and 58.5±4.6 points versus 46.0±6.3 and 46.1±6.7 points, respectively) (P<0.05). For both elite and high-level players, 95% limits of agreement statistics also indicated that the test showed good test–retest reliability (2.1±7.9 and 0.2±10.8, respectively). Due to the clinimetric properties of the test, we conclude that the Approach-Iron Skill Test is suitable for further examination with the players examined in this study.  相似文献   

15.
Abstract

The purpose of this study was to compare estimates of test reliability obtained from two sequential testing plans—trials-to-criterion (TTC) and sequential probability ratio (SPR) testing—when reliability is defined as the consistency of classification. Data from a golf chip test given to 110 beginning golf students (n = 80 males; n = 30 females) at the University of Wisconsin were used for analysis. Test specifications for the SPR test were α = β = .05, θ0 =.70, and θ1 = 50. Two mastery levels for the TTC test were examined, .70 and .60, with success criteria ranging from R = 6 to R = 12. For each sequential testing plan, both P and kappa were calculated to estimate reliability. Results for the total group and for gender indicated that reliability was higher with the SPR test when the mastery level was .70, while reliability was similar under both plans at a mastery level of .60. Median test lengths for the group were 21 for the SPR test and an average of 12 across all R values for the TTC test. Misclassification error rates for the TTC test, however, were substantially higher than under the SPR test, particularly for false nonmaster errors. These data suggest that SPR testing would be the preferred approach when misclassification errors are of primary importance, such as to determine minimal competency for certification. However, TTC testing is a viable alternative for classroom tests because of ease of administration and shorter test length.  相似文献   

16.
Abstract

Conventional ANOVA procedures for estimating intraclass reliability of a test consisting of a series of repeated trials yield overly-biased estimates of the reliability coefficient when errors in the responses are autocorrelated. The direction and amount of bias depend on the type and magnitude of error autocorrelation present in the trial responses, as well as the relative size of true variance to error variance. Examples of these biases are presented by considering specific alternatives to the classical test theory model, namely two first-order time series models.  相似文献   

17.
Abstract

The purpose of this investigation was twofold: (a) to examine the feasibility of using mathematical probability models to evaluate scoring systems; and (b) to actually examine, by use of the model, the relative merits of various tennis scoring systems. The hypothesized model was a Markov chain with stationary transition probabilities, the total chain being divided into an initial process and a random walk. By assessing a constant probability p that player A would win a point against his opponent B, and applying probability theory to the initial Markov process and the random walks, the probability that A would win the match was calculated. This was done for each of the various scoring systems. Under the assumption that the “best” player was the one with the highest probability of winning a point, the scoring method which would most frequently result in this best player being declared the winner was ascertained. Further analysis yielded the expected number of points that would be played in a match, thus giving an indication of the efficiency of the scoring system. Data from the 1967 professional tennis tour for 14 matches (350 games) between Rod Laver and Andres Gimeno were applied to the model and yielded results agreeing very closely with the hypothesized outcomes.  相似文献   

18.
Abstract

The aim of this study was to examine the effect of concentric warm-up exercise on eccentrically induced changes in muscle strength, range of motion, and soreness of the elbow flexors. Ten resistance-exercise naïve participants performed intermittent incremental eccentric actions (42 in total) of the elbow flexor muscles of each arm to induce muscle damage. The arms of each participant were randomly assigned either to a pre-eccentric exercise warm-up involving intermittent concentric exercise (warm-up) or no prior exercise (control). Strength, range of motion, and ratings of soreness were recorded before and 1, 2, 3, 4, and 7 days after exercise. Strength, range of motion, and soreness during muscular movements changed over time (P at most 0.01; Cohen's d at least 0.51, medium). There was an interaction (P < 0.001) for strength, showing a smaller reduction after exercise for warm-up than control (P < 0.001, d = 2.44, large effect). The decreased range of motion was less for warm-up than control for the arm while extended (P < 0.001), flexed (P = 0.002), and relaxed (P = 0.004). Muscle soreness was reduced for the warm-up group, while the muscle was flexed, extended, and relaxed compared with control (P < 0.001). The results demonstrate that a concentric warm-up exercise attenuates the reduction in loss of strength, range of motion, and muscle soreness after eccentric-exercise-induced muscle damage and might allow higher intensities of training to be performed.  相似文献   

19.
Abstract

The purpose of this study was to assess the test–retest reliability and criterion validity the Self-Administered Physical Activity Checklist (SAPAC) translated into the Greek language. To evaluate reliability, 72 students (35 girls and 37 boys) of the fifth and sixth grade completed SAPAC on two separate occasions, two weeks apart. Internal consistency was determined with Cronbach alpha coefficient and test–retest reliability with the intraclass correlation coefficient (ICC). To evaluate criterion validity, the RT3 Research Tracker accelerometer was used as standard measure, in 90 randomly selected Greek children (51 girls and 39 boys), aged between 10 and 13. Each subject participated for two consecutive days. On day one, an accelerometer was fitted when school started. On day two, the accelerometers were returned and each subject completed the questionnaire. The internal consistency and the test–retest reliability of SAPAC on total metabolic equivalent (MET) score, MET score of low physical activities (LPA) and MET score of moderate to vigorous physical activities (MVPA) were very satisfactory (all Cronbach's alpha > 0.87, and all ICC > 0.85, P <0.001). The Kendall's tau-b test revealed that the degree of agreement between SAPAC and RT3 accelerometer on total MET score and MET score of MVPA were 0.31 and 0.37, respectively (P <0.01). It was concluded that the Greek translated version of SAPAC is a reliable questionnaire that provides valid estimates of total, as well as moderate to vigorous activities MET scores.  相似文献   

20.
ABSTRACT

This study aimed to compare the reliability and magnitude of velocity variables between 3 variants of the bench press (BP) exercise in participants with and without BP training experience. Thirty males, 15 with and 15 without BP experience, randomly performed 3 variants of the BP on separate sessions: (I) concentric-only, (II) fast-eccentric and (III) controlled-eccentric. The mean velocity (MV) and maximum velocity (Vmax) of the concentric phase were collected against 3 loads (≈30%1RM, 50%1RM, and 75%1RM) with a linear velocity transducer. Reliability was high regardless of the variable, BP variant, and load (coefficient of variation [CV] ≤ 4.47%, intraclass correlation coefficient [ICC] ≥ 0.87). The comparison of the CVs suggested a higher reliability for the fast-eccentric BP (8 out of 12 comparisons), followed by the concentric-only BP (5 out of 12 comparisons), and finally the controlled-eccentric BP (never provided a higher reliability). No differences in reliability were observed between experienced (CV ≤ 4.71%; ICC ≥ 0.79) and non-experienced (CV ≤ 6.29%; ICC ≥ 0.76) participants. The fast-eccentric BP provided the highest MV (p < 0.05) and no differences were observed for Vmax. These results support the assessment of movement velocity during the fast-eccentric BP even in participants without experience.  相似文献   

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