• The Korean Journal of Applied Statistics
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• v.22 no.6
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• pp.1249-1263
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• 2009

The power function in sample size determination has to be characterized by an appropriate statistical test for the hypothesis of interest. Nonparametric tests are suitable in the analysis of ordinal data or frequency data with ordered categories which appear frequently in the biomedical research literature. In this paper, we study sample size calculation methods for the Wilcoxon-Mann-Whitney test for one- and two-dimensional ordinal outcomes. While the sample size formula for the univariate outcome which is based on the variances of the test statistic under both null and alternative hypothesis perform well, this formula requires additional information on probability estimates that appear in the variance of the test statistic under alternative hypothesis, and the values of these probabilities are generally unknown. We study the advantages and disadvantages of different sample size formulas with simulations. Sample sizes are calculated for the two-dimensional ordinal outcomes of efficacy and safety, for which bivariate Wilcoxon-Mann-Whitney test is appropriate than the multivariate parametric test.

• The Journal of Korean Academic Society of Nursing Education
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• v.16 no.1
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• pp.129-139
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• 2010

Purpose: A new scale was developed to measure personal power and ability for health care and promotion including health determinants. Method: Research phases designed for this study were a literature review, scale development, discussion with experts, pre-test for content validity, and survey for construct validity and reliability. The scale was composed of 20 items on 4 point Likert scale and was tested on middle aged Korean-Americans (110) and Koreans (105) living in a community. Result: As the result of factor analysis, 7 dimensions were identified that were similar yet different from the original dimensions. They included health literacy, socialbelonging and gender role, self-perception, health policy participation, socio-cultural interpersonal relationships, spiritual comfort, and socioeconomic involvement. The total variances explained 59.73%. The reliability was .736 of Cronbach's alpha. The mean PPHC was not different in age, gender, economic status and disease presence, but significantly different in country where living, religion, education level, job presence, and emigration period. The increased power group perceived more wellbeing and less depression, high internal locus of control and increased power with others. In addition, they had a greater health promotion lifestyle profile. Conclusion: This scale was statistically reliable and valid to measure personal power of health care.

• The Journal of Advanced Prosthodontics
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• v.11 no.5
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• pp.262-270
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• 2019

PURPOSE. The purpose of this in vitro study was to evaluate the marginal misfits of three-unit frameworks fabricated with conventional and digital impressions techniques. MATERIALS AND METHODS. Thirty brass canine and second premolar abutment preparations were fabricated by using a computer numerical control machine and were randomly divided into 3 groups (n=10) as follows: conventional impression group (Group Ci), Cerec Omnicam (Group Cdi), and 3shape TRIOS-3 (Group Tdi) digital impression groups. The laser-sintered metal frameworks were designed and fabricated with conventional and digital impressions. The marginal adaptation was assessed with a stereomicroscope at ${\times}30$ magnification. The data were analyzed with 1-way analysis of variances (ANOVAs) and the independent simple t tests. RESULTS. A statistically significant difference was found between the frameworks fabricated by conventional methods and those fabricated by digital impression methods. Multiple comparison results revealed that the frameworks in Group Ci (average, $98.8{\pm}16.43{\mu}m$; canine, $93.59{\pm}16.82{\mu}m$; premolar, $104.10{\pm}15.02{\mu}m$) had larger marginal misfit values than those in Group Cdi (average, $63.78{\pm}14.05{\mu}m$; canine, $62.73{\pm}13.71{\mu}m$; premolar, $64.84{\pm}15.06{\mu}m$) and Group Tdi (average, $65.14{\pm}18.05{\mu}m$; canine, $70.64{\pm}19.02{\mu}m$; premolar, $59.64{\pm}16.10{\mu}m$) (P=.000 for average; P=.001 for canine; P<.001 for premolar). No statistical difference was found between the marginal misfits of canine and premolar abutment teeth within the same groups (P>.05). CONCLUSION. The three-unit frameworks fabricated with digital impression techniques showed better marginal fit compared to conventional impression techniques. All marginal misfit values were clinically acceptable.

• Journal of Family Relations
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• v.23 no.3
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• pp.105-130
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• 2018

Objective: In this study, we examined the psychometric properties of the Korean Intergenerational Psychological Ambivalence Scale (KIPAS) for young adult children. Method: Data came from 1,140 Korean young adults aged 19-34, who were never married and had at least one living parent. We translated the individual-subjective dimension of Zygowicz's (2006) Intergenerational Ambivalence Scale from English to Korean. The individual-subjective dimension had eight items that directly measured intergenerational psychological ambivalence (D-KIPAS) and 10 items that indirectly measured intergenerational psychological ambivalence (I-KIPAS). Results: The D-KIPAS and I-KIPAS items showed good internal consistency both for the mother and the father. Confirmatory factor analysis showed that D-KIPAS items loaded on one factor after controlling for method effects, which allowed error variances among the four non-reversed items to covary. Both the positive and negative items of I-KIPAS had good reliability and loaded on the same factor. The mean score of D-KIPAS and the calculated score of I-KIPAS were significantly but moderately correlated, which indicates that the D-KIPAS and I-KIPAS assess correlated but distinct aspects of intergenerational ambivalence. Correlations among D-KIPAS, I-KIPAS, and the proxy variables of intergenerational solidarity and conflict supported the discriminant validity of the KIPAS. Conclusion: The results of this study suggest that both D-KIPAS and I-KIPAS are reliable and valid tools to measure intergenerational psychological ambivalence among Korean young adults.

• Journal of Families and Better Life
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• v.24 no.5 s.83
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• pp.53-68
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• 2006

This study examines Korean and American undergraduate students' intimacy toward the grandmother and their attitudes toward the elderly and aging. The study also identifies the variances that influence undergraduate students' attitudes. The subjects were 397 Korean and 364 America undergraduates. Statistical analysis was conducted to examine frequency, percentage, meat standard deviation, Cronbach's ${\alpha}$, t-test, Duncan test, ANOVA, and stepwise multiple regression. The results of this study were as follows; 1) Both Korean and American undergraduates' attitudes were mid-range, but their intimacy level toward their grandmother was high. 2) The Korean undergraduates' intimacy level differed significantly according to sex and religion, and it showed a significant correlation with attitudes toward the elderly and aging traits, when the student had lived with and had frequent contact with the grandmother. The American undergraduates' intimacy level, however, was significantly different according to the presence of the grandmother. There was also had a significant correlation with the undergraduate students' attitudes toward the elderly and aging traits, frequency of contact with the grandmother and year. 3) The variables that affect the Korean undergraduates' intimacy level toward the grandmother were attitude, cohabitation with her, gender, frequency of contact with the grandmother, and religion, which explained about 21% of total variance. Attitudes toward the elderly and aging traits were very important variables for Korean undergraduates' intimacy with their grandmother. The American undergraduates' intimacy was affected by the variables of attitude, frequency of contact with the grandmother, year, and the presence of the grandmother, which explained about 19% of the total variance. Attitude toward the elderly and aging traits were the most important variables for American undergraduates' intimacy with their grandmother.

• Fashion & Textile Research Journal
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• v.9 no.4
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• pp.380-390
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• 2007

The purpose of this study(Part I) was to provide the guidance in more objective and proper clothing design and wearing rule to make good image making by analysis of fashion sensibilities about adult women's town wear in unlimited circumstance. The specific objectives were; 1)to investigate about fashion sensibility of women's town wear at season 2)to investigate about fashion sensibilities of women's town wear of properties which are age, marriage or not, job, average income per month, and schooling. 3)to compare fashion sensibility between Good and Bad women's town wear. The collected photos at shopping mall, department stores, and churches(S/S, F/W:2004.4.28~2005.5.1) were prepared removing face and background that can affect in estimator and attached on gray board. To investigate fashion sensibilities, the stimulus were 80 photos('good':40, 'Bad':40). The questionnaire consisted of bi-polar 25 pairs adjective scale of fashion sensibilities was distributed 60 female(20's~40's) living in Busan. The data were analyzed by t-test, ANOVA, and Scheffe. The results of this study are summarized as follows; For fashion sensibilities at 'Good' and 'Bad' wear, the variances(season, age, marriage or not, job, average income per month, and schooling) are important. Especially, the fashion sensibility at 30's women are very unique and importance age zone to catch both young women's fashion sensibility and old women's fashion sensibility, Through that age zone, we could read women's various fashion sensibility and prospect complicate consumers' fashion mind. This study result will be utilized in the clothing design for target age zone of women's town wear, database of wearing rule and good image making, and planning fashion marketing strategies.

• The Korean Journal of Applied Statistics
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• v.25 no.1
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• pp.15-27
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• 2012

We have studied the realized variance(RV) of intra-day returns and market microstructure noise based on high-frequency stock transaction data for the four largest companies in terms of market capitalization in the KOSPI. First, non-negligible biases are observed for the RV and for the bias-corrected realized variance($RV_{AC_1}$) which is constructed by adjusting RV for the first order autocorrelation in intra-day returns. Bias is more obvious for the RV and the $RV_{AC_1}$ when intra-day returns are sampled more frequently than every 2 minutes. Transaction Time Sampling(TTS) is shown to be better than Calendar Time Sampling(CTS) in terms of biases of the RV and the $RV_{AC_1}$ for the 4 companies. The analysis reveals that market microstructure noise is temporally dependent. Second, by using the Noise-to-Signal Ratio(NSR), we estimate sampling frequencies that are optimal in terms of the Mean Square Errors(MSE) of the RV and the $RV_{AC_1}$. The optimal sampling frequencies are around 200 for RV and is around 5000 for the $RV_{AC_1}$ for all the four stock prices. For the 6 hour transaction period of the Korean stock trading, these correspond to about 2 minutes and 6 seconds.

• Journal of the Korean Data and Information Science Society
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• v.26 no.6
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• pp.1367-1375
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• 2015

Consider the linear growth models for longitudinal data analysis. Several kind of linear growth models are selected such as time-effect and random-effect models as well as a dummy variable included model. In this work, simulation data are generated with normality assumption, and both binormal ROC curve and AUC are obtained and compared for various linear growth models. It is found that ROC curves have different shapes and AUC increase slowly, as values of the covariance increase and the time passes for random-effect models. On the other hand, AUC increases very fast as values of covariance decrease. When the covariance has positive value, we explored that the variances of random-effect models increase and the increment of AUC is smaller than that of AUC for time-effect models. And the increment of AUC for time-effect models is larger than the increment for random-effect models.

• Journal of KIISE:Information Networking
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• v.30 no.4
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• pp.504-512
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• 2003

In this paper, we propose a new adaptive dissolve detection method based on the analysis of a dissolve modeling error which is the difference between an ideally modeled dissolve curve with no correlation and an actual dissolve curve including a correlation. The proposed dissolve detection method consists of two steps. First, candidate dissolve regions are extracted using the characteristics of a downward convex parabola, then each candidate region is verified based oil the dissolve modeling error. If the dissolve modeling error for a candidate region is less than a threshold defined by the target modeling error with a target correlation, the candidate region is determined as a resolve region with a lower correlation than the target correlation. The threshold is adaptively determined based on the variances between the candidate regions and the target correlation. By considering the correlation between neighbor scenes, the proposed method is able to be a semantic scene-change detector. The proposed method was tested on various types of data and its performance proved to be more accurate and reliable regardless of variation of variance of test sequences when compared with other commonly use methods.

• Korean Journal of Applied Biomechanics
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• v.13 no.1
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• pp.63-72
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• 2003

This study is examine and analysis of the most flying and run distance during swing three times with six balls between two amateurs and pro-golfers in golf field in Sungnam airport. During down swing, kinetics variances are velocity of club-head and balls, vertical angular velocity. this scientic data present amateur golfers with recognition of long flying distances for golf balls. Through this study, the conclusions are as follows. 1. Before impact the balls, The club-head velocity of amateur golfers and pro-golfers show 33.34 - 39.53m/s, 39.04 - 42.82m/s respectively during the down swing. But The club-head velocity, flight and Run distances comparative $K_1$ amateur golfer with the pro-golfer are similar. 2. After impact the balls, The balls velocity if amateur golfers show 53.04 - 61.57m/s, The pro-golfers show 62.32 - 63.4m/s respectively during the down swing. In case of $K_3$,$K_4$, After the impact balls velocity comparative The RA brand with other brand are similar, Flight and Run distance are difference. 3. After impact the balls, The balls velocity are difference to other brand but The long flight and Run distance arrange RA, BIG, TITL. 4. In the vertical flight angle of the ball after impact, amateur golfer showed 16.75 - $18.73^{\circ}$. The pro-golfer showed 15.03 - $16.04^{\circ}$. In the vertical flight angle of the balls ideal $12-13^{\circ}$, The long flight and Run distance approach In the vertical flight angle the balls $12-13^{\circ}$.