• Korean Journal of Culture and Social Issue
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• v.18 no.3
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• pp.329-347
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• 2012

Criminal media such as dramas and movies are growing in popularity. However, the effects of criminal media as well as its psychological mechanism are not clearly examined. Based on social learning theory (Bandura, 1978), past studies showed that arrest and punishment to the criminal in media have a suppressing effect. The present research examined the ironic possibility that media coverage of punishment could increase the audience's criminal intention and proposed the mediating role of counterfactual thinking in the effect. We hypothesized that when punishment was depicted as accidental rather than unavoidable in media coverage, perceived high mutability and counterfactuals focusing on the accidental factors could clarify the ways to commit the crime without being caught and subsequently increase future criminal intention. In this study, 95 college students read a story of plagiarizing either no, accidental, or inevitable punishment, and later asked to report their intention to plagiarize. An ANCOVA with participants' own history of plagiarism as a covariate found that the intention of plagiarism in future was significantly different. The results showed that the intention of plagiarism in the accidental punishment condition was higher than that in the inevitable punishment condition. Further, the intention of plagiarism in the accidental punishment condition was the same level with non-punishment condition. The findings suggest that whether criminals are caught or not is not enough to reduce criminal intentions of audience, but how criminals are caught matters.

• The Korean Journal of Applied Statistics
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• v.36 no.5
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• pp.415-445
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• 2023

Oftentimes, the time dependent treatment covariate and the time dependent confounders exist in observation studies. It is an important problem to correctly adjust for the time dependent confounders in the propensity score analysis. Recently, In the survival data, Hade et al. (2020) used a propensity score matching method to correctly estimate the treatment delay effect when the time dependent confounder affects time to the treatment time, where the treatment delay effects is defined to the delay in treatment reception. In this paper, we proposed the Cox model based marginal structural model (Cox-MSM) framework to estimate the treatment delay effect and conducted extensive simulation studies to compare our proposed Cox-MSM with the propensity score matching method proposed by Hade et al. (2020). Our simulation results showed that the Cox-MSM leads to more exact estimate for the treatment delay effect compared with two sequential matching schemes based on propensity scores. Example from study in treatment discontinuation in conjunction with simulated data illustrates the practical advantages of the proposed Cox-MSM.

• Journal of Korean Elementary Science Education
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• v.42 no.4
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• pp.591-604
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• 2023

This study investigated the impact of elementary science classes using metaverse on the academic achievement, positive experience in science, and digital literacy of elementary school students. In addition, we examined their perceptions. The respondents were derived from two classes in the sixth grade at an elementary school in Gyeonggi-do, who were selected designated as the experimental (n=29 students) and comparative (n=29) groups, respectively. Across five lessons under the "Plant Structure and Function" unit, the experimental group conducted science classes using the metaverse, whereas the comparative group conducted general textbook-based classes. To investigate instructional effects, the study performed ANCOVA using the pre-test score as a covariate, a survey on the perception of students about science classes using metaverse, and conducted interviews with a number of subjects. The result demonstrated that science classes using metaverse exerted no significant effect on scientific academic achievement and digital literacy. However, the study observed a statistically significant effect on science learning emotion which is a sub-element of positive experiences in science. The students were positively aware of science classes using metaverse in terms of interesting and diverse activities, and free expression of inquiry results and perceived the instability of smart devices and network connections as regrettable. Finally, the study posed the implications of the use of metaverse in science classes.

• The Korean Journal of Applied Statistics
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• v.37 no.2
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• pp.225-237
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• 2024

In the analysis of competing risks data, some of covariates may not be fully observed for some subjects. In such cases, excluding subjects with missing covariate values from the analysis may result in biased estimates and loss of efficiency. In this paper, we studied multiple imputation and the augmented inverse probability weighting method for regression parameter estimation in the cause-specific proportional hazards model with missing covariates. The performance of estimators obtained from multiple imputation and the augmented inverse probability weighting method is evaluated by simulation studies, which show that those methods perform well. Multiple imputation and the augmented inverse probability weighting method were applied to investigate significant risk factors for the risk of death from breast cancer and from other causes for breast cancer data with missing values for tumor size obtained from the Prostate, Lung, Colorectal, and Ovarian Cancer Screen Trial Study. Under the cause-specific proportional hazards model, the methods show that race, marital status, stage, grade, and tumor size are significant risk factors for breast cancer mortality, and stage has the greatest effect on increasing the risk of breast cancer death. Age at diagnosis and tumor size have significant effects on increasing the risk of other-cause death.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.151-157
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• 2005

Sheep production is affected by genetic and non-genetic factors. A knowledge of these factors is essential for efficient management and for the accurate estimation of breeding values. The objective of this study was to establish the non-genetic factors which affect birth weight and weaning weight in Dorper, Mutton Merino and indigenous Sabi sheep breeds. A total of 2,625 birth and weaning weight records from Grasslands Research Station collected from 1991 through 1993, were used. The records were collected from indigenous Sabi (939), Dorper (807) and Mutton Merino (898) sheep. A mixed classification model containing the fixed effects of year, birth status and sex was used for identification of non-genetic factors. Sire within breed was included as a random effect. Two factor interactions and three factor interactions were important in indigenous Sabi, Mutton Merino and Dorper sheep. The mean birth weights were 4.37${\pm}$0.04 kg, 4.62${\pm}$0.04 kg and 3.29${\pm}$0.04 kg for Mutton Merino, Dorper and Sabi sheep, respectively. Sire had significant effects (p<0.05) on birth weight in Mutton Merino and indigenous Sabi sheep. Year of lambing had significant effects (p<0.05) on birth weight in indigenous Sabi, Mutton Merino and Dorper sheep. The effect of birth status was non significant in Dorper and Mutton Merino sheep while effect of birth status was significant on birth weight in indigenous Sabi sheep. In Indigenous Sabi sheep lambs born as singles (3.30${\pm}$0.05 kg) were 0.23 kg heavier than twins (3.07${\pm}$0.05 kg), in Mutton Merino lambs born as singles (3.99${\pm}$0.08 kg) were 0.07 kg heavier than twins (3.92${\pm}$0.08 kg) and in Dorper lambs born as singles (4.41${\pm}$0.04 kg) were 0.02 kg heavier than twins (4.39${\pm}$0.04 kg). On average males were heavier than females (p<0.05) weighing (3.32${\pm}$0.04 kg vs. 3.05${\pm}$0.07 kg) in indigenous Sabi, 4.73${\pm}$0.03 kg vs. 4.08${\pm}$0.05 in Dorper and 4.26${\pm}$0.07 kg vs. 3.66${\pm}$0.09 kg in Mutton Merino sheep. Two way factor interactions of sire*year, year*sex and sex*birth status had significant effects (p<0.05) on birth weight in indigenous Sabi, Mutton Merino and Dorper sheep while the effect of year*birth status was non significant on birth weight in Indigenous Sabi sheep. The three way factor interaction of year*sex*birth status had a significant effect (p<0.01) on birth weight in indigenous Sabi and Mutton Merino. Tupping weight fitted as a covariate had significant effects (p<0.001) on birth weight in indigenous Sabi, Mutton Merino and Dorper sheep. The mean weaning weights were 17.94${\pm}$0.31 kg, 18.19${\pm}$0.28 kg and 14.39${\pm}$0.28 kg for Mutton Merino, Dorper and Indigenous Sabi sheep, respectively. Effects of sire and sire*year were non significant on weaning weight in Dorper and Mutton Merino while year, sex and sex*year interaction had significant effects (p<0.001) on weaning weight. On average males were heavier than females (p<0.001) at weaning. The respective weaning weights were 18.05${\pm}$0.46 kg, 18.68${\pm}$0.19 kg, 14.14${\pm}$0.15 kg for males and 16.64${\pm}$0.60 kg, 16.41${\pm}$0.31 kg, 12.64${\pm}$0.32 kg for females in Mutton Merino, Dorper and Indigenous Sabi sheep. Lambs born as singles were significantly heavier at weaning than twins, 0.05 kg, 0.06 kg and 0.78 kg for Mutton Merino, Dorper and Indigenous Sabi sheep, respectively. Effect of tupping weight was highly significant on weaning weight. The three way factor interaction year*sex*birth status had a significant effect (p<0.01) on weaning weight. Correction for environmental effects is necessary to increase accuracy of direct selection for birth weight and weaning weight.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.1
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• pp.8-19
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• 2020

Objectives : The purpose of this study was to examine whether the MMPI-2-RF serves as a useful tool to differentiate between the subtypes of high risk of suicide among psychiatric outpatients. Methods : Patients were recruited from the department of psychiatry of university hospital. Participants were diagnosed using DSM-5 criteria by board certified psychiatrists. Their medical records were reviewed retrospectively. And participants were put into 4 groups (Suicide ideation, Suicide attempt, Non-suicidal self-injury, and general psychiatric diagnosis as a control group). For statistical comparison, the MANCOVA with gender as a covariate was used. Results : The results indicated that as previous research with non-clinical sample suggested, psychiatric outpatients with high suicide risk also have significantly higher Emotional/Internalizing Dysfunction, Helplessness/Hopelessness, Suicidal/Death Ideation, Demoralization, Cognitive complaints, Cynicism, Dysfunctional negative thoughts than general psychiatric patients group. But group differences within the high suicide risk patients have not been observed. However, suicide attempt group and NSSI group has higher Behavioral/Externalizing Dysfunction, RC4, AGG than general psychiatric patients group. But there was no difference between suicidal idea group and general psychiatric patients group. Conclusions : There was no group difference observed between all three subtypes, which mean the MMPI2-RF may not be the useful diagnostic tool to navigate high suicide risk subtypes. Even though there was no difference observed in the suicide ideation group, suicide attempt group and NSSI group have higher aggression and externalization. So those indexes could serve as a useful marker to investigate riskiness of suicide related symptoms.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.12
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• pp.1696-1702
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• 2015

The objective of this study was to compare the effects of body weight growth adjustment methods on genetic parameters of body growth and tissue among three pig breeds. Data collected on 101,820 Landrace, 281,411 Yorkshire, and 78,068 Duroc pigs, born in Korean swine breeder farms since 2000, were analyzed. Records included body weights on test day and amplitude (A)-mode ultrasound carcass measures of backfat thickness (BF), eye muscle area (EMA), and retail cut percentage (RCP). Days to 90 kg body weight (DAYS90), through an adjustment of the age based on the body weight at the test day, were obtained. Ultrasound measures were also pre-adjusted (ABF, EMA, AEMA, ARCP) based on their test day measures. The (co)variance components were obtained with 3 multi-trait animal models using the REMLF90 software package. Model I included DAYS90 and ultrasound traits, whereas model II and III accounted DAYS90 and pre-adjusted ultrasound traits. Fixed factors were sex (sex) and contemporary groups (herd-year-month of birth) for all traits among the models. Additionally, model I and II considered a linear covariate of final weight on the ultrasound measure traits. Heritability ($h^2$) estimates for DAYS90, BF, EMA, and RCP ranged from 0.36 to 0.42, 0.34 to 0.43, 0.20 to 0.22, and 0.39 to 0.45, respectively, among the models. The $h^2$ estimates of DAYS90 from model II and III were also somewhat similar. The $h^2$ for ABF, AEMA, and ARCP were 0.35 to 0.44, 0.20 to 0.25, and 0.41 to 0.46, respectively. Our heritability estimates varied mostly among the breeds. The genetic correlations ($r_G$) were moderately negative between DAYS90 and BF (-0.29 to -0.38), and between DAYS90 and EMA (-0.16 to -0.26). BF had strong $r_G$ with RCP (-0.87 to -0.93). Moderately positive $r_G$ existed between DAYS90 and RCP (0.20 to 0.28) and between EMA and RCP (0.35 to 0.44) among the breeds. For DAYS90, model II and III, its correlations with ABF, AEMA, and ARCP were mostly low or negligible except the $r_G$ between DAYS90 and AEMA from model III (0.27 to 0.30). The $r_G$ between AEMA and ABF and between AEMA and ARCP were moderate but with negative and positive signs, respectively; also reflected influence of pre-adjustments. However, the $r_G$ between BF and RCP remained non-influential to trait pre-adjustments or covariable fits. Therefore, we conclude that ultrasound measures taken at a body weight of about 90 kg as the test final should be adjusted for body weight growth. Our adjustment formulas, particularly those for BF and EMA, should be revised further to accommodate the added variation due to different performance testing endpoints with regard to differential growth in body composition.

• Korean Journal of Biological Psychiatry
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• v.3 no.2
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• pp.222-239
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• 1996

The purpose of this study was to evaluate the effects of alcohol on the psychomotor performance and subjective assessment in healthy Korean adults with acetaldehyde dehydrogenase I(ALDH-I) isozyme variance. A total of 20 male subjects, half with active ALDH-I and the other half with inactive ALDH-I, were selected through both a self-reporting questionnaire examining alcohol sensitivity and the Higuchi's ethanol patch test detecting ALDH-I deficiency. In a doule-blind, placebo-controlled cross-over design, each subject consumed four doses of alcohol(0.25, 0.5, 0.75, 1.0g/kg) and placebo on five separate occasions at weekly intervals, Treatment order was fully balanced using a $5{\times}5$ Latin square, Psychomotor performance tests[coritical flicker fusion threshold(CFF) and choice reaction time(CRT)] and self-estimate questionnaires were conducted at baseline and at time points of 20, 40, 60, 90, 120, 150, 180 minutes after consuming the test drug for 20 minutes, Blood alcohol concentrations(BACs) using breath analyzer were measured at baseline and at time points of 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 150, 180 minutes after drinking, The BACs and the mean changes in the psychomotor performances and subjective assessments from pre-alcohol baseline, were compared between the two groups. The findings were summarized as follows : 1) BACs were tended to be higher in the inactive group than the active in all of the four alcohol doses. However significant group differences were only after the 0.5g/kg dose of alcohol. 2) The inactive group showed significant impairment in CFFT at most time points alter 0.75 and 1.0g/kg doses of alcohol. 3) In CRT, total reaction time(TRT) significantly prolonged in the inactive group than the active group at 20 minutes after 0.25 and 1.0g/kg doses of alcohol and at 40, 60, 90 minutes alter 0.75g/kg dose of alcohol. In the inactive group, recognition time component significantly increased at 20, 60, 90 minutes after 1.0g/kg dose of alcohol, while movement time component significantly increased at 40, 60 minutes after 0.75g/kg dose of alcohol. 4) Subjective evaluation of the effect of alcohol revealed that physical and mental conditions as well as a self-estimate of the effects of alcohol on performance were significantly worse in the inactive group than the active at some time points alter all of the lour alcohol doses, wihch were more pronounced after 0.75 and 1.0g/kg doses of alcohol. 5) Most of the group differences mentioned above, still remained statistically significant after BAC was entered as a covariate, These findings demonstrated that the alcohol sensitivity is higher in individuals with inactive ALDH-I than those with active ALDH-I both on the subjective assessments and the objective psychomotor performances. Furthermore, these results suggest thai the alcohol sensitivity may be determined by acetaldehyde concentration rather than BAC per se. In future studies, after more accurate genotyping for ALDH-I, the relationships between BAC, acetaldehyde concentration and alcohol sensitivities should be clearly defined.

• Journal of agricultural medicine and community health
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• v.27 no.1
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• pp.87-98
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• 2002

This study is to reveal the overall level of loneliness, depression and social supports of the elderly in rural area of Korea. The interview survey was performed in February 2001 with structured questionnaires to 486 respondents of 65 years or more of age who lived in Muan-gun area. The questionnaire was the revised translation of Japanese Elderly Study Which was composed of general characteristics, Japanese Loneliness Scale, abridged General Depression Scale(GDS) and Duke University social support Inventory. The following analyses adopted the analysis of covariate, t-test, and Chi- squire were used for some of the cross- sectional analyses. Average age of 486 respondents was 73.9 years old. 58.0% of the respondents noticed their partner or son as the primary consultant for the stressful situation. 56.2% of the respondents experienced the loss of their marital partner, health and/or friends. Average score of loneliness, GDS and social supports of the respondents that was each $35.54{\pm}8.38$, $7.23{\pm}2.21$ and $26.01{\pm}.90$. The overall level of depression seemed to be low as the 'pleasure to be alive' and 'happiness' scored high while the 'state of anger' and 'ominous presentiment' scored low. The level of loneliness and depression was positively correlated while the relationships were negative between loneliness and support and between depression and social support. These results suggested that social and health promotional programmes be necessary for the elderly of rural area. Further research would be required to specify the necessities.

• The Korean Journal of Nuclear Medicine
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• v.32 no.3
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• pp.225-237
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• 1998

Purpose: We investigated the statistical methods to compose the functional brain map of human working memory and the principal factors that have an effect on the methods for localization. Materials and Methods: Repeated PET scans with successive four tasks, which consist of one control and three different activation tasks, were performed on six right-handed normal volunteers for 2 minutes after bolus injections of 925 MBq $H_2^{15}O$ at the intervals of 30 minutes. Image data were analyzed using SPM96 (Statistical Parametric Mapping) implemented with Matlab (Mathworks Inc., U.S.A.). Images from the same subject were spatially registered and were normalized using linear and nonlinear transformation methods. Significant difference between control and each activation state was estimated at every voxel based on the general linear model. Differences of global counts were removed using analysis of covariance (ANCOVA) with global activity as covariate. Using the mean and variance for each condition which was adjusted using ANCOVA, t-statistics was performed on every voxel To interpret the results more easily, t-values were transformed to the standard Gaussian distribution (Z-score). Results: All the subjects carried out the activation and control tests successfully. Average rate of correct answers was 95%. The numbers of activated blobs were 4 for verbal memory I, 9 for verbal memory II, 9 for visual memory, and 6 for conjunctive activation of these three tasks. The verbal working memory activates predominantly left-sided structures, and the visual memory activates the right hemisphere. Conclusion: We conclude that rCBF PET imaging and statistical parametric mapping method were useful in the localization of the brain regions for verbal and visual working memory.