• Journal of Korean Society for Quality Management
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• v.36 no.4
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• pp.1-6
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• 2008

As more and more data are collected one may ask whether the data collected within a short period of time are same. In this case traditional hypothesis testing of $H_o:{\mu}_1={\mu}_2$ vs $H_1:{\mu}_1{\neq}{\mu}_2$ is used to determine whether the data are same when there is no knowledge about equivalence testing. However, this type of hypothesis testing has the undesirable property of penalizing higher precision. So TOST is to be performed in the event of equivalence testing. In this study equivalence testing is introduced where one can find the applications in industry. Traditional two sample t testing is to be compared with the equivalent testing and the procedure to perform the equivalence testing is to be presented along with an example. Finally equivalence testing in terms of the other parameters such as variance, proportion or failure rate is to be sought.

• Journal of Korean Society for Quality Management
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• v.22 no.4
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• pp.102-110
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• 1994

We investigate the small-sample behavior of the probability of rejection curves and its performance for a equivalence testing procedure based on confidence intervals which was developed with a motivation from bioequivalence studies. This type of equivalence studies are conducted frequently in pharmaceutical industries to compare the relative bioavailabilty of two formulations of a drug and can be applied various fields where assurance of quality equivalence is needed. From the Monte-Carlo simulation results we suggest proper sample sizes for the equivalence testing procedure.

• Journal of the Korean Statistical Society
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• v.23 no.1
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• pp.199-206
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• 1994

Sometimes a researcher with a view of conventional significance testing rejects his/her hypothesis, even through it could have not been rejected with a smaller sample. This can be a logical dilemma for a researcher who wants to "prove" a hypothesis rather than to show discrepancy from a null hypothesis. In this study, a new testing paradigm called equivalence testing via confidence interval will be developed so that it is suitable for the purpose of statistical proof.cal proof.

• The Korean Journal of Applied Statistics
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• v.21 no.5
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• pp.867-873
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• 2008

It is a convention to use 5% significance level when a statistical test is employed for clinical data. But when a confidence interval is used for testing equivalence, 90% confidence interval has often been used. When $1-{\alpha}$ confidence interval is used for hypothesis testing, its significance level is often ${\alpha}$. So it makes a confusion that the significance level is 10% if 90% confidence interval is employed for testing equivalence. In this paper I will clarify this issue by reviewing relevant papers and conducting simulation studies. I hope that it will be beneficial to statisticians in pharmaceutical companies, CROs, university hospitals.

• Communications for Statistical Applications and Methods
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• v.5 no.2
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• pp.491-501
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• 1998

Motivated by bioequivalence studies which involve comparisons of pharmaceutically equivalent dosage forms, we propose a more general decision rule for showing equivalence simultaneously between multiple means and a control mean. Namely, this testing procedure is concerned with the situation in that one must make decisions as to the bioequivalence of an original drug product and several generic formulations of that drug. This general test is developed by considering a spherical confidence region, which is a direct extension of the usual t-based confidence interval rule formally approved by the U.S. Food and Drug Administration. We characterize the test by the probability of rejection curves and assess its performance via Monte-Carlo simulation. Since the manufacturer's main concern is the proper choice of sample sizes, we provide optimal sample sizes from the Monte-Carlo simulation results. We also consider an application of the generalized equivalence test to a repeated measures design.

• Journal of Korean Academy of Nursing
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• v.36 no.8
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• pp.1295-1300
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• 2006

Purpose. The purposes of this methodologic paper are to (1) describe theoretical background in conducting research across different cultures; (2) address measurement issues related to instrument administration; and (3) provide strategies to deal with measurement issues. Methods. A thorough review of the literature was conducted. A theoretical background is provided, and examples of administering instrument in studies are described. Results. When applying an instrument to different cultures, both equivalence and bias need to be established. Three levels of equivalence, i.e., construct equivalence, measurement unit equivalence, and full score comparability, need to be explained to maintain the same concept being measured. In this paper, sources of bias in construct, method, and item are discussed. Issues related to instrument administration in a cross-cultural study are described. Conclusion. Researchers need to acknowledge various group differences in concept and/or language that include a specific set of symbols and norms. There is a need to question the philosophical and conceptual appropriateness of an assessment measure that has been conceptualized and operationalized in a different culture. Additionally, testing different response formats such as narrowing response range can be considered to reduce bias.

• Transactions of the KSME C: Technology and Education
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• v.5 no.2
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• pp.105-113
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• 2017

KOLAS (KOrea Laboratory Accreditation Scheme) belongs to APLAC (Asia Pacific Laboratory Accreditation Cooperation). KOLAS manages the accreditation scheme for measurement traceability to SI units. As per June 2016, there are 22 KOLAS laboratories for liquid flow metering. Among them, 12 laboratories participated in the proficiency test (PM2015-08) for water flow metering, organized by KASTO (Korea Association of Standards and Testing Organizations). This proficiency test was performed with three kinds of flow ranges ($3.6m^3/h{\sim}12m^3/h$, $40m^3/h{\sim}80m^3/h$, $40m^3/h{\sim}200m^3/h$) considering the CMC (calibration and measurement capability) of the participating laboratories. The purpose of the proficiency test was to find out measurement equivalence of the CMC's between each participating laboratory and the reference testing laboratory (KRISS). The measurement equivalence was tested by the number of equivalence ($E_n$). If ${\mid}E_n{\mid}$ < 1, the measurement equivalence was established. All the participating laboratories passed this proficiency test.

• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.1-8
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• 1997

The main purpose of the Boolean equivalence problem is to verify that two Boolean expressions have the same functionality. Simulation has been extensively used as the standard method for the equivalence problem. Obviously, the number of tests required to perform a satisfactory coverage grows exponentially with the number of input variables. However, formal methods as opposed to simulation are getting more attention from the community. We propose a new algorithm called the Cover-Merge Algorithm based on a derivational method using the concept of cover and merge for the equivalence problem and investigate its theoretical aspects. Because of the difficulty of the problem, we emphasize simplification techniques in order to reduce the search space or problem size. Heuristics based on types of merges are developed to speed up the derivation process by allowing simplifications. In comparison with widely used technique called Binary Decision Diagram or BDD, the algorithm proposed outperforms BDD in nearly all cases of input including standard benchmark problems.

• Journal of Computing Science and Engineering
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• v.4 no.4
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• pp.313-349
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• 2010

In this paper, we study the data interoperability problem of web services in terms of XML schema compatibility. When Web Service A sends XML messages to Web Service B, A is interoperable with B if B can accept all messages from A. That is, the XML schema R for B to receive XML instances must be compatible with the XML schema S for A to send XML instances, Le., A is a subschema of B. We propose a formal model called Schema Automaton (SA) to model W3C XML Schema (XSD) and develop several algorithms to perform different XML schema computations. The computations include schema minimization, schema equivalence testing, subschema testing, and subschema extraction. We have conducted experiments on an e-commerce standard XSD called xCBL to demonstrate the practicality of our algorithms. One experiment has refuted the claim that the xCBL 3.5 XSD is backward compatible with the xCBL 3.0 XSD. Another experiment has shown that the xCBL XSDs can be effectively trimmed into small subschemas for specific applications, which has significantly reduced the schema processing time.

• Journal of the Korea Safety Management & Science
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• v.12 no.2
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• pp.217-223
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• 2010

The research proposes the complementary methodology using integrated hypothesis testing and confidence interval models that can be identified the statistical difference and practical equivalence. The models developed in this study can be used in the quality improvement processes such as QC story 15 steps. For the expressions of CI4LSD(Confidence Interval for Least Significant Difference) and CI4TOST(Confidence Interval for Two One-Sided Tests) are simple, quality practioners can efficiently handle them. CI4TOST models as a complement can be applied when CI4LSD models are influenced by sample size and precision.