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Purpose The purpose of this study was to examine the efficacy of different cartoon viewing devices during phlebotomy in children. Design This study was a prospective, randomized controlled trial. Methods The study included inpatients from the Biochemical Laboratory of a private university hospital in Turkey and was conducted between September 2017 and April 2018. A computer-based random number generator was used to randomly assign the patients into three groups (virtual reality [VR], tablet, and control) with 40 children each. Data were collected using the Wong-Baker FACES Pain Rating Scale and the Children's Fear Scale. Pain and anxiety scores were reported by children, parents, and observers in tablet and control groups. In the VR group, pain and anxiety were determined only by children's reports. Findings According to the children reports, the VR group reported significantly less pain and anxiety than those in the tablet and control groups (P Conclusions The cartoon distraction performed using a VR device reduced the perception of pain and anxiety during phlebotomy in school-age children.

Background Cutibacterium acnes is the most common pathogen in shoulder prosthetic joint infections. Short-contact benzoyl peroxide (BPO) solutions effectively reduce C acnes loads on the shoulder preoperatively. It is unknown how long the effect of BPO lasts. We evaluated C acnes counts 1 week after BPO application. We hypothesized that BPO would decrease C acnes burden with a rebound after 1 week. Methods Screening of 102 healthy volunteers with no history of shoulder surgery or C acnes infection was performed to establish bacterial counts. Thirty-four participants were selected based on an established threshold. Each was given BPO 5% for 3 consecutive days of application on either the left or right shoulder as indicated by a random number generator. Deep sebaceous gland cultures were obtained with a detergent scrub technique before BPO application, after 3 days of use, and 1 week after BPO treatment commenced. Results The differences between the logarithmic reduction and the logarithmic rebound at the anterior, lateral, and posterior sites were statistically significant. Anteriorly, the average log reduction was −0.44 and the average log rebound was 0.69 (P = .003). Laterally, reduction was −0.64 and rebound was 0.74 (P = .003). Posteriorly, reduction was −0.63 and rebound was 0.78 (P = .008). At the axilla, reduction was −0.40 and rebound was 0.31 (P = .10). The differences in C acnes burden between pretreatment and 1-week counts at all sites were not statistically significant. Conclusion A significant decrease in C acnes burden occurred after BPO application but was not permanent. Significant rebound occurred just 1 week later.

This study was aimed at verifying the possibility of mentally influencing from a distance an electronic device based on a True Random Number Generator (TRNG). Thirteen adult participants contributed to 100 trials, each comprised of three samples of data each of 15 minutes’ duration: one for mental pre-interaction, one for mental interaction, and one for mental post-interaction. For each of these samples, at the end of each minute, the data sequence generated by the random number generator was analysed with two specific tests called “Frequency” and “Runs”, in order to determine the degree of randomness of the sequence. The only evidence of an effect of distant mental interaction is an average increase of approximately 50%, with respect to control data, of the number of samples within which the pre-determined statistical threshold was exceeded in both tests. Although the effect of distant mental interaction is still weak, we believe that the results of this study represent a proof-of-concept for the construction of electronic devices susceptible to distant mental influence.

The chaos driven discrete artificial bee colony (CDABC) algorithm is introduced in this paper. Four unique chaos maps of Burgers, Lozi, Delayed Logistic and Tinkerbell are embedded as chaos pseudo-random number generators and compared with the Mersenne Twister pseudo-random number generator. Two unique problems of quadratic assignment and capacitated vehicle routing problem are solved using five different variants of the algorithm and analytical comparison is conducted. Furthermore, paired t-test is done pairwise on all variants, and from these results it is ascertained that the Tinkerbell variant of CDABC is the best performing for both problem classes.

Although random responding is prevalent and increases Type II errors, most psychologists avoid trying to identify it because the means to do so are extremely limited. We propose the inter-item standard deviation (ISD), a statistical index of response variance, is suited for this task. We hypothesized that random responders produce large ISDs because they respond to items all over a measure’s response range, whereas conscientious responders produce small ISDs because they respond to items more consistently. We administered a questionnaire containing the NEO-FFI-3 and an embedded validity scale to 134 university students. Another 134 responders were created using a random number generator. For all 268 responders, the ISD was calculated for each of the NEO-FFI-3′s five subscales and an aggregated ISD was calculated by averaging the five ISD indexes. Results showed that (1) random responders produce significantly larger ISDs than conscientious responders, (2) the ISDs were strongly correlated with the embedded validity scale and with one another, and (3) the ISDs correctly identified responders with greater than 80% classification accuracy. The mean ISD yielded greater than 95% classification accuracy. This study shows that responders can be identified by quantifying inter-item response variance.

We present a random number generator (RNG) testing application in LabVIEW®, based on six of the statistical tests from the ubiquitous NIST test suite that is widely used in the field of cryptography. The implementation is described, and tests measuring performance, both regarding precision and speed, are demonstrated. The application can be interfaced to real time true RNGs based on quantum optics experiments.

We establish average bounds on the partial quotients of fractions b/p, with p prime, b taken in a multiplicative subgroup of (Z/pZ)⁎ and for “most” primitive elements b. Our result improves upon earlier work due to G. Larcher. The behavior of the partial quotients of b/p is well known to be crucial to the statistical properties of the pseudo-congruential number generator (modp). As a corollary, estimates on their pair correlation are refined.

The aim of the study is to evaluate the influence of random errors of the stochastic technological process occurring in a batch type plant on the homogeneity of the hot-mix asphalt (HMA). The article presents the algorithm of prognosing mineral part composition of HMA, which takes into consideration a variation of mineral material cumulative percent passing through control sieves as well as errors of mineral material dose weight in the finite dosing. It is considered that percent passing and dose weight errors are independent random quantities, distributing according to the normal law. The original algorithm for the simulation of values of these two quantities is used. The mineral material grading and dose weight of the batches of HMA are selected through the use of the random number generator. To evaluate the homogeneity of the simulated lot of HMA batches, reference was made to Lithuanian Construction Recommendations R35-01, limiting the admissible deviations of components quantities of HMA in comparison with the job-mix formula. The example of simulation discussed above is presented, and the results are analysed.

A widely used pseudo-random number generator has been shown to be inadequate by today's standards. In producing a revised generator, extensive use has been made of a test package TestU01 for random number generators. Using this, criteria have been devised for the revised generator-also other high-quality generators have been identified. Facilities have been devised to allow the new generator to be used in a highly parallel environment, which is likely to be a feature of many future applications.

A method for model parameter identification as incorrect inverse problem solution has been proposed. Iterative regularization procedure and a numerical algorithm have been developed for the case of two-parameter models. The method has been tested in two cases concerning both linear and non-linear relationships between objective function and parameters. Random number generator has been employed for “experimental” data used in the parameter identification procedure. Initial approximation effects on both the identified parameters and the regularization parameter have been investigated. Statistical approach for the analysis of the model adequacy has been proposed.

Anthelmintic resistance has become an increasing problem particularly to gastrointestinal tract nematodes and appropriate methods are required to detect this phenomenon so the correct action can be taken. This paper compares a number of mathematical techniques that are used to analyse data. The negative binomial distribution is a mathematical distribution used to model aggregated data and hence is suitable to model the intensity of parasite burden and the magnitude of the faecal egg counts. Maximum likelihood techniques are utilised to exploit this mathematical distribution to analyse the magnitude of the faecal egg count reduction and decline in the worm burden in response to anthelmintic treatment. Data from experimental groups of sheep described in the accompanying paper are used. In addition, simulated data sets of faecal egg counts were created using a random number generator following appropriate negative binomial distributions. The results demonstrate this statistical model can detect evidence of anthelmintic resistance with a faecal egg reduction test that otherwise might require a slaughter trial to demonstrate. In addition, the simulated data sets confirm that there is a significant probability of failure to detect low anthelmintic efficacy with commonly used mathematical techniques. Consequently, the use of maximum likelihood mathematical techniques with a negative binomial statistical model would aid in the early detection of anthelmintic resistance using faecal egg count reductions and result in a lower probability of inappropriately assigning an anthelmintic as effective.

The most efficient and easiest way for implementing a multiple recursive random number generator is the approximate factoring (AF) method. In the literature, the AF method can be applied in the three types of restriction on multiplier. This paper considers the effectiveness and efficiency of these restrictions from the theoretical and empirical points of view. The most effective and efficient restriction is presented. The number of arithmetic operations required by the AF method is also discussed.

We describe a random number generator that produces uniform [0,1) variates directly, as 64-bit floating point numbers, without the customary floating of integers. Using only subtraction and tests on magnitude, the method is readily implemented and should, given the same seed values, produce exactly the same random numbers with most programming languages. The resulting numbers have a very long period (≈2 202 or 10 61 ) and apparently excellent randomness—supported by extensive testing.

Because the values of most of the parameters controlling the occurrence and severity of a drought in a given location are unknown, and no periodicity has been observed, droughts can be considered random events. Running a random number generator within the limits of the annual rainfall variability relevant to the Maya lowlands, and defining a “Lean Year”, it is observed that strings of lean years occur quite frequently. Defining “Severe Drought”, “Disaster”, and “Catastrophe” based on the length of these strings, it is observed that a severe drought occurs on average every 32 years, a disaster occurs on average every 130 years, and a catastrophe on average every 500 years. These values fit the measured variability of the Yucatan climate, as observed in lake core sediments and in the post conquest written records. It also fits the average occurrence of “megadroughts” in the US Great Plains. The fit between the random occurrence model and the actual, “measured” occurrence of droughts supports the notion that for all practical purposes, droughts had been random events in the Maya region and could not be predicted. The lack of evident periodicity could be one of the reasons why means for long-term storage of food products were not developed there. It may also have affected the relationship between the priesthood and the general populace in that region. Since the method described here can be applied to any climatic region once the rainfall variability and the sensitivity of the local agriculture are known or can be estimated, if similar results are found they may probably have affected other regions with other ancient cultures in a similar way.

The problems that rendered Excel 97 unfit for use as a statistical package have not been fixed in either Excel 2000 or Excel 2002 (also called "Excel XP"). Microsoft attempted to fix errors in the standard normal random number generator and the inverse normal function, and in the former case actually made the problem worse.

This paper considers the problem of generally and efficiently generating random numbers (RNs) for the multiple recursive generators with unrestricted multipliers. A new algorithm based on the decomposition method is proposed. The new algorithm improves the decomposition method in terms of both generality and efficiency. It is shown to be suitable for the signed and unsigned magnitude number systems on a computer, and to require fewer numbers of arithmetic operations than the decomposition method. Several randomly constructed numerical examples illustrate the low variance and efficiency of the new algorithm compared with the decomposition method for various computers.

The combined random number (RN) generator has been considered by many scholars as a good RN generator. One promising type of combined RN generator, recommended by L'Ecuyer (Oper. Res. 44 (1996) 816; 47 (1999) 159), is the combined multiple recursive generator (MRG). This paper analyzes the combined MRG via the Chinese remainder theorem. A new combined generator based on the generalized Chinese remainder theorem and on the Ore algorithm (Amer. Math. Monthly 59 (1952) 365) is presented. The proposed combined generator improves the combined MRG in terms of both the suitability for various types of RN generators and the restriction on the moduli of the individual generators. Therefore, the proposed combined generator is an ideal RN generator and is most recommended.

Controversy still exists on whether rhythmic features such as beach cusps are the result of the presence of standing edge wave motions in the hydrodynamics or if they are the result of self-organising processes. The compatibility between the two mechanisms is here investigated through the use of a numerical model simulating the formation and development of beach cusps. Simulations characterised by different forcing conditions have been performed. A series of ‘random’ simulations, each individual run simply differing from the others in the seed used in the random number generator, showed the typical self-organisation behaviour with the features appearing at different locations and even with slightly different spacing. ‘Regular’ series of simulations have been run by changing the wavelength of the template superimposed by the hydrodynamic forcing and the number of cycles when the template was present. Results surprisingly indicate that even a minimum number of cycles with a regular forcing can deterministically induce the final shoreline configuration. Furthermore, if the forcing template has the same wavelength as the one resulting from purely random simulations, growth rates are much faster than those obtained with random conditions. Implications for the kind of field measurements necessary to discern which of the two mechanisms is responsible for beach cusp formation have also been considered.

We generalize the exact solution to the logistic map. The new chaotic functions in some cases are exact solutions to new classes of chaotic maps, but in general they are truly unpredictable random functions. They can help in the generation of truly random numbers.

In the learning from positive examples framework, finding minimal concepts consistent with a given positive sample is a natural way to avoid over-generalization. We show in this paper that finding a minimal 1-DNF consistent with a positive sample is LOGSNP-complete. We use random number generator techniques to prove this result.

Every random number generator has its advantages and deficiencies. There are no ‘‘safe’’ generators. The practitioner’s problem is how to decide which random number generator will suit his needs best. In this paper, we will discuss criteria for good random number generators: theoretical support, empirical evidence and practical aspects. We will study several recent algorithms that perform better than most generators in actual use. We will compare the different methods and supply numerical results as well as selected pointers and links to important literature and other sources. Additional information on random number generation, including the code of most algorithms discussed in this paper is available from our web-server under the address http://random.mat.sbg.ac.at/ # 1998 IMACS/Elsevier Science B.V.

A mathematical model was used to examine the effect that uncertainty might have on future best choices for the total allowable catch (TAC) and minimum length. Its outputs are estimates of annual fishing mortality and effort (required to achieve the TAC), catch rate, mean individual weight, exploited density, and population fecundity. Uncertainty about the fixed inputs to the model, and variation in the annual recruitment to the stock, were simulated with a random number generator. Reduction in the minimum length was shown to be associated with the need for less annual effort to achieve the TAC. The variability of the effort was also reduced. The effect of increasing the TAC was to increase the effort and its variability. Lower and more variable population fecundities resulted from increase in the TAC, and also from reduction in the minimum length. When the model included a stock-recruitment relationship, a high TAC with a low minimum length was shown as likely to cause fishery collapse. The probability of collapse was reduced when the magnitude of the TAC was adjusted according to the population fecundity of the previous year. Combinations of adjustable TAC and minimum length were identified which achieved higher although more variable yields, higher and less variable catch rates, and low probabilities of fishery collapse.

We consider the problem of deterministically selecting s uniformly random different m-element subsets of (1), h., k. The only known lower bound for the time to solve this problem is the trivial Ω(sm). The best two previously known solutions are of time O(sm3log m log log m) and O(s(k + m)), respectively. In this paper we present an algorithm whose time complexity is O(s2m2 + sm2 log m log log m + sm log sm). Thus, for s < m log m log log m this algorithm is the fastest known deterministic algorithm. The main idea of the algorithm is using a uniform random number generator to efficiently construct biased random numbers.

In a recent article Chang et al. [Computers Ops Res. 21, 199–204 (1994)] investigated the prime modulus M = 32,749 and recommended 227 multipliers selected among 10,912 candidate multipliers. This study examines the multipliers by using the spectral test and points out some weaknesses in the proposed generator. An alternative generator is presented having very long period and satisfactory statistical properties.

We find lower and upper bounds for the price of Bermudan basket options by Monte-Carlo simulation through regression and look at the impact of the choice of random number generator, as well as whether including in-the-money paths or not in the regression.

A Fortran 90 MODULE has been implemented which is used to replace the intrinsic random number generation subroutines RANDOM_NUMBER and RANDOM_SEED with a user-defined generator. It is shown how the new features of Fortran 90 can be used to define a set of user subroutines that behave as the intrinsic procedures do, and thus provide a convenient way to interface to arbitrary random number generators without the need to change the calls to the random number generator in the user program. Implementation examples demonstrate how to call an “external” generator as well as how to integrate an algorithm into the module.

A new very flexible generator of the GFSR type has been constructed, and is examined, thus providing users with numerous different pseudorandom streams from one package. While the software associated with this article is only for Intel-based PCs, some of the statistical conclusions should also apply to other machines for which this algorithm could be programmed.

In searching for statistically sound multipliers for the prime modulus multiplicative congruential random number generator, both theoretical and empirical tests are conducted extensively over one hundred thousand primitive roots of the ten largest primes in 2 15 . Sixty-two multipliers pass all the tests to possess good global and local statistical properties. It is worthwhile to note that the empirically tested multipliers recommended in some previous studies are not on this list. The conclusion is that both theoretical and empirical tests are mandatory to sieve out good multipliers.

The Birnbaum-Saunders distribution has been shown to be the failure time distribution for fatigue failure in particular and for stochastic wear-out failure in general. In this paper, the random number generator for Birnbaum-Saunders distribution is addressed. In testing the proposed approaches several large samples were generated with various combinations of the paramenters. The probability plot is further applied to check the goodness-of-fit of each sample.

A library containing highly portable implementations of most algorithms for (pseudo) random number generation has been developed, which might be used in any area of simulation which requires random number generators. Each generator is freely configurable by the user, so the RANEXP library is particularly well-suited for applications requiring different random number generators. The algorithms are implemented in C, but are callable from Fortran application program also.

In searching for statistically sound multipliers for the prime modulus multiplicative congruential random number generator for 16-bit microcomputers, an exhaustive analysis is conducted over the 10,912 primitive roots of the modulus 215 − 19 = 32,749. The result shows that there are only 227 good multipliers among the 10,912 candidate multipliers. Here a multiplier is said to be good if its corresponding generator has good statistical properties and computational efficiency.

The effect of noise on the triadic 1D Cantor set is studied. The iterative procedure used to generate the Cantor set is modified by adding a stochastic variable to the interval length at each iteration. It is found that the presence of this ‘noise’ truncates the self-similar structure of the set after a finite number of iterations. Either the noise causes the closest spaced intervals to merge together, or it causes all the intervals to collapse to a set of a finite number of points. Distribution functions are found describing the probability that self-similarity was destroyed on the nth iteration. A program using a random number generator was written that simulates our modified Cantor procedure. The results of 100 000 simulations are compared with the predictions of the probability distribution functions. Good agreement is found.

By studying a different system, we verify the correlations found recently in a popular random number generator by Ferrenberg et al. We find indeed that the dominant correlations are too long ranged to be seen by them, and we check a number of further RNGs.

Audit is now part of any laboratory service. Histopathology is no exception, and we have set up a system which allows us to review 4% of our specimens. These specimens are identified using a random number generator and reviewed by a consultant pathologist. Both slides and wet specimens are reviewed and graded according to a set scheme. The results from the first year of operation (1990) show a high rate of accuracy with no serious diagnostic disagreements between the auditor and the reporting pathologist. However, some errors which we would wish to prevent were detected and the audit has allowed us to take corrective measures. In our opinion, this form of audit is useful and necessary to maintain good clinical practice. The cost is considerable--histopathology is by its nature labour intensive. Recognition of this fact by health boards is essential if such systems are to continue.

A solute dispersion model with random variable porosity is considered in the present study. A spectrum of longitudinal random porosities is generated by the random number generator to illustrate the applications and to assess its effect on the solute dispersion. The complicated governing dispersion model can be conveniently tackled by an implicit finite difference method. It is shown that if the random porosity function does not deviate more than 92 , 70 and 34% from its average, the dispersion model using average porosity can, respectively, predict an average solute concentration within 15 , 10 and 5% of that of the random variable porosity model.

Early in cohabitations of pairs of bowl and doily spiders, Frontinella pyramitela (Linyphiidae), males and females court and pseudocopulate with no transfer of sperm, then may proceed to true copulations during which sperm are transferred. A male assesses female virginity during courtship and pseudocopulation. Only if the female is a virgin will he build a sperm web, charge his pedipalps with sperm, and then begin insemination. The data also indicate that (1) the male's assessment of the female's virginity depends on a signal (in contrast to a structural change) given by the female, and (2) the female can signal ‘virgin’ but not ‘non-virgin’. Males that do not assess the females as virgin continue with pseudocopulations for highly variable periods of time (up to 4·5 h) and the decision to cease is apparently governed by a stochastic process, analogous to a random number generator, in the male. In constrast, the timings of other events (e.g. the virginity signal and the end of true copulation) during these reproductive behaviours are governed by quite different processes: the data are consistent with a model involving the steady accumulation or dissipation of some substance or drive.

An efficient method is presented which implements the start-up from noise in numerical simulations of free-electron lasers in the steady state. The method is related to the one described by Penman and McNeil [Optics Comm. 90 (1992) 82], but has the advantage that it does not need the use of a random number generator, so it lacks a statistical spread in the simulation results.

In this paper a method for comparison of pseudo-random number generators which have uniform distributions in the interval [0, 1] is proposed. With the suggested criterion, it is better to use a pseudo-random number generator whose distribution of the pseudo-random variable is closer to the ideal uniform distribution. The application of the suggested method is illustrated by an example.

In a previous note [1] with the above title, Coldwell demonstrated the manifestation of a defect in a special random number generator and discussed methods [2] to circumvent this defect. The purpose of this note is to draw attention to other devices which may serve for the same intent.

The advance architecture and software of Fujitsu's new vector machines, the FACOM VP-100/200, allow one to extract maximum performance from a program by FORTRAN coding. Three examples of basic algorithms, i.e., triangularization of a symmetric matrix, a radix-2 FFT, and a random number generator, are implemented on the VP-200 to exemplify the effectiveness of the well-balanced compiler capability against the VP architecture.

A novel dynamic bias technique for the 8085A microprocessor has been developed which uses a random number generator both to produce an instruction sequence and to exercise the control functions.

We show that using RANF may lead to wrong results when lattice models are simulated by Monte Carlo methods. We present a shift-register sequence random number generator which generates two random numbers per cycle on a two pipe CDC Cyber 205.

The iterative scheme described by Milstein [6] is used to estimate the rate constants of a model describing an inducible enzyme system. The model was formulated by Heinmets [5], and was mathematically analyzed by Roth and Roth [9] using Bellman's quasilinearization technique. The method used in this article makes use of multiple trajectories of the system to obtain a set of parameters which fit the data of all trajectories simultaneously. A comparison of the numerical results is presented. The data used in the calculations were generated in a similar way to that of Roth and Roth. However, we introduce into each datum 5% noise from a random number generator uniformly distributed [0,1].

A new class of random-number generators is described, based on a combination of the logical exclusive-or operation and the McLaren-Marsaglia mechanism. It is suitable for any word length, requires no multiple-precision arithmetic, and contains no hard-to-determine constants. Though no theory is available, numerical tests have shown it to be very satisfactory. Execution time is less than twice that of standard congruential generators.

The Ising ferromagnet is a well-known model of a system of interacting spins which is amenable to Monte Carlo calculation involving: 1. (a) Boolean work and low precision counting; 2. (b) conditional choice of transition probabilities; 3. (c) high quality 24-bit random number generation (RNG); 4. (d) comparison of transition probabilities with random numbers. An assembler implementation on the 64 × 64 DAP has achieved 42 × 10 6 spin updates per second on a 64 × 64 × 64 problem using a standard DAP random number generator (RNG) that has recently been speeded up by a factor of eight. A later implementation involves: 1. (a) a new RNG that is an order of magnitude faster still, mainly achieved by producing data in greater bulk; 2. (b) a rewrite of the code including a form of parallel table look up for the transition probabilities; 3. (c) an increase in the problem size to 128 × 128 × 144. The performance is 218 × 10 6 spin updates per second. This compares with 22 × 10 6 on a CYBER 205 and 24 × 10 6 on special purpose hardware built by a group in Santa Barbara, both on 64 × 64 × 64 problems. Our results can be extrapolated to about 40 × 10 6 spin updates per second for a possible 32 × 32 DAP which would be about two times faster than a CYBER 205 and two orders of magnitude cheaper.

A simulation model which reflected the seasonal dynamics of biomass in a North America mixed prairie was employed to evaluate methods of calculating aboveground net primary production from harvest data. The methods of calculating aboveground net primary production were evaluated under conditions with and without variability in the data. A multivariate normal random number generator was utilized in the variance case. In the no variance case, methods which utilized only live biomass underestimated aboveground net primary production by approximately 42%. Methods which utilized live and recent dead (senesced) biomass produced estimates very close to the model value. Variance in the data resulted in overestimation of aboveground net primary production with the degree of overestimation related to the sampling frequency. Use of a simple simulation model which simultaneously makes use of all the data to arrive at an estimate of aboveground net primary production may prove to be superior to the statistical estimators.