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We introduce a fully parametric approach for updating beliefs regarding correlated binary variables, after marginal probability assessments based on information of varying quality are provided by an expert. This approach allows for the calculation of a predictive joint density for future assessments. The proposed methodology offers new insight into the parameters that control the dependence of the binary variables, and the relation of these parameters to the joint density of the probability assessments. A comprehensible elicitation procedure for the model parameters is put forward. The approach taken is motivated and illustrated through a practical application. [ABSTRACT FROM AUTHOR]

B. E. Wampold, T. Minami, S. C. Tierney, T. W. Baskin, and K. S. Bhati (2005) re-analyzed trials included in our systematic review of randomized clinical trials that compared placebo with no treatment (A. Hróbjartsson & P. C. Gøtzsche, 2001). Based on 11 trials, B. E. Wampold et al. concluded that “ ... the placebo effect is robust” (p. 850). We (2001) concluded, based on 130 trials, that “we found little evidence in general that placebos have powerful clinical effects” (p. 1599). In this commentary, we examine the reasons for this discrepancy. For trials with continuous outcomes, our analyses (82 trials) and that of B. E. Wampold et al. (5 trials) resulted in pooled standardized mean differences that were small and essentially identical: -0.28 (95% confidence interval = -0.38 to -0.19) versus -0.29 (95% confidence interval = -0.52 to -0.06). There was considerable risk of bias (e.g., reporting bias, sample-size bias). Similarly, for trials with binary outcomes, our analysis (32 trials) and that of B. E. Wampold et al. (6 trials) found no statistically significant pooled effect of placebo interventions and were essentially identical: relative risk 0.95 (95% confidence interval = 0.88–1.02) versus odds ratio 0.99 (95% confidence interval = 0.81–1.23). Thus, B. E. Wampold et al.'s conclusion was not substantiated by their data, and is best characterized as powerful spin. © 2007 Wiley Periodicals, Inc. J Clin Psychol 63: 373–377, 2007. [ABSTRACT FROM AUTHOR]

The Cranfield test collection was designed for laboratory-based information retrieval (IR) experimentation in the late 1950s and gave a basic model for test collections currently in use. The basic model has been quite resistant to changes while minor modifications have been made. For example, in the Cranfield collection, documents were assessed using a five-level relevance scale. The judge was asked to estimate the value of a document in answering the problem presented in the search question. Typical of the later collections, the notion of relevance has been simplified to cover only topicality aspects that are measured on a binary scale. Text REtrieval Conference has established an evaluation practice where the binary relevance scale is combined with liberal relevance criteria. The threshold for accepting a document relevant to a topic is very low. The use of binary assessments has been criticized for the lack of realism. For example, studies on Web searching have raised the need for improving the capability of IR systems in finding highly relevant documents at the expense of marginally relevant ones.

Although various methods exist in soft decision decoding methods for block codes, of those that can be applied to linear and nonlinear coding, there are not many with low levels of computation that provide high levels of performance. In this paper, a method is proposed that reduces computation requirements while maintaining performance close to that of maximum likelihood decoding by a decision-making procedure in which a candidate codeword table is referenced by performing Euclidean distance comparisons on the received signal's hard decision binary sequence. The computation requirements and the block error rate performance are investigated through computer simulation to demonstrate the effectiveness of the proposed method in nonlinear β codes in additive Gaussian noise channels and fading channels. These results show that the block error rate performance of the proposed method in the additive Gaussian noise channel is about the same as the performance of the Chase 11 algorithm and is only slightly inferior to that of maximum likelihood decoding. Concerning the amount of computations, it is possible to reduce the complexity down to about 1% of that required by maximum likelihood decoding, and also the complexity can be reduced below that of the Chase II algorithm. On the other hand, in the fading channel, the block error rate performance of the proposed method, when compared to maximum likelihood decoding performance, reveals a decrease in Eb/N0 of about 1 dB, and it is seen to have good performance compared to the Chase II algorithm. Also, application toward quasi-cyclic coding/4-ary ASK coding using a candidate word table with respect to a 4-ary sequence applied with BCH coding is investigated, and superior results are obtained. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 1, 80(9): 56–67, 1997 [ABSTRACT FROM AUTHOR]

In the conventional coding of the facsimile signal, codes such as modified Huffman (MH) and modified Reed (MMR) codes have been used, where the statistical properties of the image are assumed as known and the image is assumed as stationary. In practice, however, it is not always adequate to represent the probabilistic structure of the image data by a single model. It is desirable to employ a code whose coding parameters can be adjusted according to the variation of the statistical properties. The arithmetic code can realize independently the symbol coding and the probability estimation, and the dynamic, modification of the coding parameters is easy. From such a viewpoint, this paper proposes a new dynamic adaptive coding based on the arithmetic code. In the proposed method, the effective probability of the less probable symbol, which is the coding parameter of the arithmetic symbol, is selected from the values obtained by the approximation using a polynomial sum of the powers of 2. The algorithm of transition in each coding parameter is determined by considering both the static and the dynamic coding characteristics. In addition, a method is presented in which the decision about the stationarity is included, and the convergence from the initial value is improved by controlling the number of transition steps. As a result of simulation, it is seen that the proposed method can reduce the number of bits of the coded output by 27.2 percent on the average, compared to MMR coding. [ABSTRACT FROM AUTHOR]

Perfect AN codes are those with the least redundancy under constant code length and error correcting capability. The existence of perfect codes has been studied for generalized r-ary represented AN codes and symmetric multivalue represented AN codes to apply them to multivalued arithmetic circuits. In this paper we define single error-correcting perfect BCN (Binary Coded Decimal)-AN codes and obtain the conditions under which the perfect BCN-AN codes exist. These conditions do not depend on the weight sequence itself used in BDC representation of code words, but on the class to which the weight sequence belongs. By using these conditions we prove that for some classes of the BCD representation including (8421) representation there exists no perfect BCD-AN code. For some of the remaining classes we obtain examples of generators of perfect BCD-AN codes through exhaustive computation. [ABSTRACT FROM AUTHOR]

The article focuses on the process of reasoning in a binary computer. Computer elements have only two natural states. It is a simpler way of calculation than the decimal mode. Binary symbols start with a 0 and end with a 1. Binary digits can be manipulated in a number of ways. Arithmetic operations are similar in both the decimal and the binary system. Most of digital computers perform their tasks in binary arithmetic. Subtraction is performed through addition of the ones complement. Division may be accomplished by repeated addition of the complement. The calculus of reasoning is essentially identical with the calculus of number. The apparatus designed to mechanize calculation is also able to simulate the process of logical reasoning because of the formal identity of the rules of the logical and arithmetic calculi in binary notation.

Binary coded decimal (BCD) to 7-segment decoder with oxide thin film transistors (TFTs) was implemented on a glass to display 7-segment display from BCD. The developed BCD to the 7-segment decoder with indium-gallium-zinc oxide thin film transistors was verified up to 1 kHz operation frequency under the power supply voltage of 5 V, and converted successfully 4-bit binary input code to 7-segment inputs. The binary output voltages were 0.4 V for the low and 4.1 V for the high at an operation frequency of 500 Hz, respectively. The output signals of the developed 7-segment decoder matched well the BCD to the decimal values. The result showed that oxide TFT can be used for the integrated BCD to 7-segment decoder for the various sensing applications, particularly for wearable devices and the integrated bio sensing platform. [ABSTRACT FROM AUTHOR]