• 대한수학교육학회지:수학교육학연구
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• 제24권3호
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• pp.375-385
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• 2014

이 연구는 학교수학의 모평균과 모비율의 신뢰구간의 추정을 비교하면서 두 추정간에 일관성이 확보되고 있는지에 대해 고찰하였다. 이 결과를 토대로, 이 연구에서는 표본평균과 표본비율을 동일한 방식으로 취급하는 것, 모평균과 모비율의 신뢰구간의 예를 구성할 때 모표준편차 대신에 표본표준편차의 관측값을 대입하는 절차를 동일하게 적용하는 것, 표본비율 $\hat{P}$와 그에 대한 관측값 $\hat{p}$을 구별하는 것과 같은 일관성 확보 방안을 제안하였다.

• Journal of the Korean Statistical Society
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• 제33권3호
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• pp.323-337
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• 2004

This article coined a general class of estimators for various measures in normal population when some' a priori' or guessed value of standard deviation a is available in addition to sample information. The class of estimators is primarily defined for a function of standard deviation. An unbiased estimator and the minimum mean squared error estimator are worked out and the suggested class of estimators is compared with these classical estimators. Numerical computations in terms of percent relative efficiency and absolute relative bias established the merits of the proposed class of estimators especially for small samples. Simulation study confirms the excellence of the proposed class of estimators. The beauty of this article lies in estimation of various measures like standard deviation, variance, Fisher information, precision of sample mean, process capability index $C_{p}$, fourth moment about mean, mean deviation about mean etc. as particular cases of the proposed class of estimators.

• 핵의학기술
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• 제27권1호
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• pp.55-61
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• 2023

Purpose In this study, the monthly population distribution was calculated for statistical verification of 10 tests (CA19-9, CA15-3, testosterone, PTH, calcitonin, AFP, CEA, CA72-4, PSA, estradiol) with changed reagents, and the trend of change By comparing and analyzing the results, we want to verify the accuracy of the results and improve the reliability of the test. Materials and Methods From June 2021 to February 2023, for the 10 items in which the reagent was changed, the monthly percentage and standard deviation index before and after the reagent change were compared, respectively. At this time, the reference value was arbitrarily set for the comparison group in consideration of the reference value of the test item, and the groups were subdivided and compared, and the standard deviation index allowed range was -2.0 or more and 2.0 or less. Results For CA19-9, CA15-3, AFP, CEA, and calcitonin 5 test items, the change in monthly ratio in all test sections before and after the reagent change was kept constant. On the other hand, for CA72-4, PSA, testosterone, PTH, and estradiol items, the standard deviation index exceeded the acceptable standard after changing the reagent. CA72-4 test items showed an increasing trend in standard deviation index in the test section exceeding the reference value. In the case of the PSA test item, the maintenance ratio of 0.04 ng/mL was significantly decreased after changing the reagent. The testosterone test item had a standard deviation index of -2.5 in the test section exceeding 10.1 ng/mL after changing the reagent, and the standard deviation index of the PTH test item was out of the acceptable range in all test sections. It was confirmed that the estradiol test item showed an overall increase in the result value. Conclusion Through this study, the continuity and accuracy of the test results could be verified. It is considered that the stability of the test can be secured by analyzing the factors affecting the test result and solving the cause for the test item whose standard deviation index is out of the acceptable standard.

• KSBB Journal
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• 제27권1호
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• pp.40-44
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• 2012

The laboratory animal group separation is dividing animal population into subgroups, which have similar average and standard deviation values among the subgroups, based on the biological characteristics such as body weight, glucose level in blood, etc. Although group separation is very important and initial step in experimental design, it needs a labor intensive process for researchers because of making similar average and standard deviation values among the subgroups using the raw biological characteristics. To reduce the labor cost and increase the efficiency of animal grouping, we developed a web program named as laboratory animal group separation (LAGS) program. This LAGS uses biological characteristics of population, number of group, and the number of elements per each subgroup as input data. The LAGS automatically separates the population into each subgroup that has similar statistical data such as average and standard deviation values among subgroups. It also provides researchers with the extraordinary data generated in the process of grouping and the final grouping results by graphical display. Through our LAGS, researchers can validate and confirm results of laboratory animal group separation by just a few mouse clicks.

• 핵의학기술
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• 제20권1호
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• pp.37-41
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• 2016

정도관리(Quality Control)는 오차를 최소한으로 하여 검사의 신뢰도를 증진 시키는 것을 목적으로 하고 있으며 이러한 정도관리 활동을 통해 환자의 진단과 치료방침에 영향을 주는 핵의학 혈액 검사의 신뢰도가 확보되고 있다. 이에 연구자들은 신뢰도 향상의 추가적인 기법으로 건강검진 수검자를 대상으로 시행한 핵의학 혈액검사의 모집단 분포를 이용한 통계적 품질관리의 유용성을 평가해 보고자 한다. 2014년 1월부터 2014년 12월까지 서울아산병원 건강증진센터를 이용한 건강검진 수검자 41,341명을 대상으로 핵의학 혈액 검사 12종목에 대해 통계 분석을 시행 하였다. 통계분석은 핵의학 혈액 검사 12종목에 대한 결과 보고 치를 참고치 이내, 참고치 이상, 참고치 이하의 세 가지 그룹의 월간 백분율로 구분하여 모집단 분포의 평균값과 표준편차, 그리고 표준편차 지수(Standard Deviation Index: SDI)를 산출 하였고 그 결과 모집단 분포의 표준편차는 모든 그룹에서 대부분 ${\pm}2SD$ 이내의 결과를 보였다. 건강검진 수검자에 대한 핵의학 혈액검사 12종목(AFP, CEA, CA19-9, CA125, PSA, TSH, FT4, Anti-Tg-Ab, Anti-TPO-Ab, Calcitonin, 25-OH-VitD3, Insulin)의 모집단 분포를 분석한 결과 월간 백분율의 표준편차 지수(SDI)가 ${\pm}2.0$ 이상인 경우는, 1월과 3월 Insulin검사에서 각각 2.3, 2.4, 5월 Anti-Tg-Ab검사에서 2.2, 그리고 9월 CA19-9에서 2.2의 결과를 보였다. 이는 검사 Kit 시약의 이상 (동위원소 시약의 최대 결합률 저하), 검사반응 시간의 저하가 원인 이었다. 연구대상이 되는 전체의 속성을 포함하고 모집단 분포의 특성을 이용한 통계적 품질관리는 검사실에서 시행하고 있는 내부정도관리 프로그램을 보완하는 역할을 할 수 있으리라 생각된다.

• 대한인간공학회지
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• 제32권3호
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• pp.237-243
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• 2013

Objective: The present study developed an estimation method of boundary zone representative humanoids(hereafter, EBZ method) using descriptive statistics on the design target population. Background: The boundary zone method(hereafter, BZ method) generates representative humanoids at a boundary zone that statistically accommodates a designated percent of the design target population; however, the BZ method has a practical limitation because it requires a large scale anthropometric database on the design target population. Method: The EBZ method developed in the present study consisted of 3 steps. In the first step, the boundary zone of accommodating a designated percent(e.g., 90%) is formed under the assumption of normal distributions for anthropometric sizes. In the second step, cases that fall within the boundary zone are estimated using descriptive statistics(mean, standard deviation, and covariance) on the design target population. In the last step, K-mean cluster analysis is conducted for the cases, and representative humanoids are selected from each of clusters. Results: Evaluation results showed that mean accommodation percent of the EBZ method was 90.9%(range: 90.8~91.1%) which is similar to the target percent(90%). In addition, standard deviation of accommodation percent for 100 repetitions was 0.1%. Lastly, the number of representative humanoids generated by the EBZ method(n = 20) was similar to the BZ method(n = 16). Conclusion: The EBZ method can generate representative humanoids which accommodate a designated percent of the design target population using descriptive statistics. Application: The EBZ method can be utilized in the generation of humanoids for ergonomic design and evaluation of products when the large scale anthropometric database on the design target population is not existed.

• Journal of the Korean Data and Information Science Society
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• 제23권6호
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• pp.1241-1247
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• 2012

The paper considers empirical Bayes (EB) and hierarchical Bayes (HB) predictors of the finite population mean under a linear regression model with measurement errors We discuss how to calculate the mean squared prediction errors of the EB predictors using jackknife methods and the posterior standard deviations of the HB predictors based on the Markov Chain Monte Carlo methods. A simulation study is provided to illustrate the results of the preceding sections and compare the performances of the proposed procedures.

• 대한인간공학회지
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• 제11권1호
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• pp.31-38
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• 1992

The population of aged people in industries has been increased remarkably due to the decline of birth rates and the increase of average life span. Also, the current automation trends makes aged people to work easy in industries since automation technologies help them to avoid physically hard tasks. Therefore the evaluation of aged workers' adaptability would be an important research topic. In the study, the mean and standard deviation of the reaction time are calculated to see the differences with four lamps's types and ages. It is found that the mean reaction time and the standard deviation are increased with the the increase of age. The quantitative approach provides an important information to be used not only for the adaptability estimation of aged workers but also for the working capability qualification for re-employment.

• 산업경영시스템학회지
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• 제20권44호
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• pp.69-79
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• 1997

We investigate both of central and dispersion tendencies of the observed test statistics in control charts in order to judge whether a production process is abnormal or not. In order to do it, first, we study about detection of changes of the population mean as a central tendency The $\bar{x}$ and x control charts are used for detecting the change of the population mean $\mu$. We shows the probability detecting the change of population mean using the $\bar{x}$ and x control charts. Secondly, we study about detection of changes of the population standard deviation as a dispersion tendency in the s control chart. In our studies, for the given several parameters the detection probabilities of changes of central and dispersion tendencies are calculated, the necessary sample size values n are suggested for detecting the changes, and their informations are given as various tables.

• 생명과학회지
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• 제14권2호
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• pp.345-350
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• 2004

한국내 물오리나무(Ainus hirsuta) 집단의 미소지리적 변이를 공간적 상관관계에 적용하였다. 분리된 등급간 대립유전자의 각 형태의 산출을 정규분포 편차 통계에서 임의분포를 하고 있는지를 검정하였다. 모든 경우에서 예상 값이 유의성을 가지는지 Moran의 I값으로 추정한 결과 120 경우 준 24 경우(20.0%)에서 유의성을 나타내었다. 이들 값 중에서 17 경우는 음의 값을 나타내었는데 이는 한국의 물오리집단이 10등급 간격에서 유사하지 않다는 점을 시사하였다. 그 한 원인으로는 화목(火木)을 위한 인간의 간섭을 추정할 수 있다. 열매를 맺는 가지나 줄기의 간헐적인 벌목에 의해 유전자 유동이 조장되었기 때문일 것이다. 한편, 그루터기나 밑둥으로부터 영양번식을 할 수 있는 능력 또한 유전적 구조를 어지럽히는 한 요인으로 작용한 것으로 사료된다.