• Title, Summary, Keyword: statistical significance

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A sample size calibration approach for the p-value problem in huge samples

  • Park, Yousung;Jeon, Saebom;Kwon, Tae Yeon
    • Communications for Statistical Applications and Methods
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    • v.25 no.5
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    • pp.545-557
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    • 2018
  • The inclusion of covariates in the model often affects not only the estimates of meaningful variables of interest but also its statistical significance. Such gap between statistical and subject-matter significance is a critical issue in huge sample studies. A popular huge sample study, the sample cohort data from Korean National Health Insurance Service, showed such gap of significance in the inference for the effect of obesity on cause of mortality, requiring careful consideration. In this regard, this paper proposes a sample size calibration method based on a Monte Carlo t (or z)-test approach without Monte Carlo simulation, and also proposes a test procedure for subject-matter significance using this calibration method in order to complement the deflated p-value in the huge sample size. Our calibration method shows no subject-matter significance of the obesity paradox regardless of race, sex, and age groups, unlike traditional statistical suggestions based on p-values.

Implementation of Statistical Significance and Practical Significance Using Research Hypothesis and Statistical Hypothesis in the Six Sigma Projects (식스시그마 프로젝트에서 연구가설과 통계가설에 의한 통계적 유의성 및 실무적 유의성의 적용방안)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management and Science
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    • v.15 no.1
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    • pp.283-292
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    • 2013
  • This paper aims to propose a new steps of hypothesis testing using analysis process and improvement process in the six sigma DMAIC. The six sigma implementation models proposed in this paper consist of six steps. The first step is to establish a research hypothesis by specification directionality and FBP(Falsibility By Popper). The second step is to translate the research hypothesis such as RHAT(Research Hypothesis Absent Type) and RHPT(Research Hypothesis Present Type) into statistical hypothesis such as $H_0$(Null Hypothesis) and $H_1$(Alternative Hypothesis). The third step is to implement statistical hypothesis testing by PBC(Proof By Contradiction) and proper sample size. The fourth step is to interpret the result of statistical hypothesis test. The fifth step is to establish the best conditions of product and process conditions by experimental optimization and interval estimation. The sixth step is to draw a conclusion by considering practical significance and statistical significance. Important for both quality practitioners and academicians, case analysis on six sigma projects with implementation guidelines are provided.

Experimental studies on anti-tumor and immunomodulatory effects of Samulbyulgapchoengpitang and one herb added (사물별갑청피탕(四物鼈甲靑皮湯)과 사물별갑청피탕가미방(四物鼈甲靑皮湯加味方)의 항암작용(抗癌作用)과 면역반응(免疫反應)에 미치는 영향(影響))

  • Kim, Dong-Ryoel
    • The Journal of Internal Korean Medicine
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    • v.15 no.2
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    • pp.174-196
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    • 1994
  • In order to investigate the effect of Samulbyulgapchoengpitang(SB) and one herb added(SBA) on anti-tumor and immune response, the author performed this experimental study, Tumor weight(TW), mean survival days(MSD) and body weight(BW) in vivo, natural killer cell activity(NKCA). rosette forming cells(RFC), phagoctic activity in recticuloendomethrial system(PA), delayed type hypersensitivity(DTH), hemoagglutinin titer(HA) and hemolysine(HL) in vitro were measured in mice. 1. MSD was prolonged in both of treated groups(SB and SBA) as compared with control group. 2. TW was decreased in both of treated groups with statistical significance as compared with control group. 3. BW was increased in both of treated groups and just only in SB with statistical significance as compared with control group. 4. DTH was increased in both of treated groups with statistical significance as compared with control group. 5. HA was increased in both of treated groups with statistical significance as compared with control group. 6. HL was increased in both of treated groups with statistical significance as compared with control group. 7. RFC was increased in both of treated groups and just only in SB with statistical significance as compared with control group. 8. NKCA was increased in both of treated groups with statistical significance as compared with control group. 9. PA was increased in both of treated groups with statistical significance as compared with control group. According to the above experimental results, it is suggested that SB and SBA will have anti-tumor substance and enhance the effect of immune response. But we have to consider the longtime prescription of SBA because there have been no experiments in its side effect or accumulation in body.

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An Experimental Study on the Effects of Shipjuntaepotang on Immune Response in Mice (소음인(少陰人) 십전대보탕(十全大補湯)이 면역반응(免疫反應)에 미치는 영향(影響))

  • Park, Seong Ho
    • Journal of Sasang Constitutional Medicine
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    • v.4 no.1
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    • pp.221-230
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    • 1992
  • In order to investigate the effects of shipjuntaepotang (少陰人 十全大補湯) on immune response, the author performed this experimental study. Delayed type hypersensitivity (DTH) and rosette forming cells (RFC) for cell-mediated immune response, hemagglutinin (HA) titers, hemolysin (HL) titers, and carbon clearance for phagocytic function of MPS (mononuclear phagocyte system) were measured in ICR mice. The results were summarized as follows. 1. DTH in the experimental group was increased, as compared with the control group, with statistical significance. 2. RFC in the experimental group was increased, as compared with the control group, with statistical significance. 3. HA-titers were increased in the experimental group, as compared with the control group, with statistical significance. 4. HL-titers were increased in the experimental group, as compared with the control group, with statistical significance. 5. Carbon clearance was increased in the experimental group, as compared with the control group, with statistical significance. Through invivo experimental study in ICR mice, these findings suggest that shipjuntaepo-tang enhance both cellmediated and humoral immune responce.

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Effects of the Ansymondam-tang and Gamiondam-tang on the Regional Brain Monoamines Contents of Cold Swimming Stressed Mice (안심온담탕(安心溫膽湯)과 가미온담탕(加味溫膽湯)이 한랭(寒冷).유영(遊泳) 스트레스 생쥐의 뇌부위별(腦部位別) Monoamines 함량(含量)에 미치는 영향(影響))

  • Kim Sung-Ho;Hwang Seon-Mi;Chung Dae-Kyoo
    • Journal of Oriental Neuropsychiatry
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    • v.12 no.1
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    • pp.97-109
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    • 2001
  • Objectives : This study aimed to evaluate the anti-stress effects of Ansymondam-tang and Gamiondam-tang on the contents of monoamines in the regional brain of mice forced cold swimming stress in $4^{\circ}C$ water. Methods : The experimental animals were forced cold swimming stress for 3 minutes, and administered of Ansymondam-tang(2.2mg/10g) and Gamiondam-tang(0.83mg/10g) extract for 7 days before stress. The monoamines contents were measured by HPLC method in various part(frontal cortex, hypothalamus, corpus striatum and hippocampus) of mice brain. Results: 1. In frontal cortex, the contents of norepinephrine were increased with statistical significantly in all of the administered group compared to control group. The contents of dopamine and serotonin were increased in Gamiondam-tang administered group has a statistical significance. 2. In hypothalamus, the contents of dopamine were increased with statistical significance in all of the administered group compared to control group. 3. In corpus striatum the contents of norepinephrine were decreased and the contents of dopamine were increased with statistical significance in all of the administered group compared to control group. The contents of serotonin were increased in Gamiondam-tang administered group has a statistical significance. 4. In hippocampus the contents of norepinephrine were decreased with statistical significance in Gamiondam-tang administered group compared to control group. The contents of dopamine were increased in Ansymondam-tang administered group has a statistical significance. Conclusion : This study reaches a conclusion that Ansymondam-tang and Gamiondam-tang has significant effects .on reducing and preventing stress in mice. Especially Gamiondam-tang is more effective in the statistical significance than Ansymondam-tang on the monoamines change in the mice brain.

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The Comparative Studies for the Anti-stress Effect of Guibitang and Ascorbic Acid on Heating and Swimming Stress (열(熱)Stress 및 유영(游泳)Stress에 대(對)한 귀비탕(歸脾湯)과 Ascorbic Acid의 항(抗)Stress효능(效能) 비교연구(比較硏究))

  • Lee Hwa-Sin;Whang Wei-Wan
    • Journal of Oriental Neuropsychiatry
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    • v.6 no.1
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    • pp.19-39
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    • 1995
  • In order to compare the anti-stress effect of Guibitang with that of ascorbic acid, after these medicines were administered to guinea pigs induced by heating and swimming stress, the changes of the weight of body and organ, and content of plasma catecholamines, serum total cholesterol, free cholesterol, triglyceride, protein, glucose and cortisol were measured. The results were as follows : 1. The weight of the body was increased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress. 2. The weight of spleen decreased with statistical significance in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress, but in case of swimming stress, the weight of spleen decreased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. The weight of adrenal decreased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress alone. 3. Plasma norepinephrine content decreased with statistical significance not only in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid but in the group administered ascorbic acid with Guibitang as compared with in the group administered ascorbic acid on heating stress. In case of swimming stress, norepinephrine decreased with statistical significance in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 4. Plasma dopamine content decreased with statistical significance only in the group administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress. 5. Serum total cholesterol content decreased with statistical significance in the groups administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress, but in case of swimming stress, it decreased with statistiscal significance only in the group administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 6. Serum triglyceride content decreased with statistical significance not only in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid but in the group administered ascorbic acid with Guibitang as compared with in the group adminstered ascorbic acid on heating stress. In case of swimming stress, triglyceride decrease with statistical significance only in the group administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 7. Serum glucose content increased with statistical significance in the groups administered Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress, particulaly in case of swimming stress, in the group administered ascorbic acid with Guibitang, it increased with statistical significance as compared with in the group administered ascorbic acid. 8. Serum cortisol content decreased with statistical significance only in the group administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress.

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Effects of Aqua-acupuncture with Woolgum on the Recovery of Liver Injury in Rats (울금약침(鬱金藥針)이 백서(白鼠)의 간손상(肝損傷) 회복(恢復)에 미치는 영향(影響))

  • Ahn Young-Min;Park Hee-Soo
    • Journal of Acupuncture Research
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    • v.15 no.2
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    • pp.237-253
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    • 1998
  • These studies were carried out to observe the effect of Aqua-acupuncture with Woolgum extract on the recovery from liver injury of rats. The liver injury of rats induced with 0.5ml/200g carbon tetrachloride. The Aqua-acupuncture with Woolgum extract solution inserted into corresponding locus of the Kansu(BL18.) in Rats. Experimental group was divided into 4 groups: Normal group, $CCI_4$-intoxicated group, Saline treated group after $CCI_4$-intoxicated and Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. Biochemical assays for each serum enzyme activity of GOT, GPT, LDH, total protein, triglyceride, albumin, WBC, neutrophils, lymphocyte were performed. The results were as follows : 1. GOT was decreased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. In GOT activity, the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated showed higher level significant compared with the saline aqua-acupuncture treated group after $CCI_4$-intoxicated. 2. GPT was decreased with statistical significance in the Woolgum aqua-acupuncture treated after $CCI_4$-intoxicated. In GOT activity, the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated showed higher level significant compared with the saline aqua-acupuncture treated group after $CCI_4$-intoxicated. 3. LDH was decreased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. 4. Total protein increased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. 5. Albumin was increased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. The saline aqua-acupuncture treated group after $CCI_4$-intoxicated was not recognized as compared with $CCI_4$-intoxicated group. 6. Triglyceride was increased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. 7. WBC was decreased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. In WBC count, the Woolgum aqua-acupuncture higher level significant compared with the saline aqua-acupuncture treated group after $CCI_4$-intoxicated. 8. Lymphocyte was decreased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. 9. Neutrophils was increased with statistical significance in the Woolgum aqua-acupuncture treated group after $CCI_4$-intoxicated. The saline aqua-acupuncture treated group after $CCI_4$-intoxicated was not recognized as compared with $CCI_4$-intoxicated group. From above results, it is suggested that the Woolgum aqua-acupuncture had significant effects on the injury induced by $CCI_4$.

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Kinematic Characteristics Based on Proficiency In Geoduepyeopchagi in Taekwondo Poomsae Koryo

  • So, Jae Moo;Kang, Sung-Sun;Hong, AhReum;Jung, Jong Min;Kim, Jai Jeong
    • Korean Journal of Sport Biomechanics
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    • v.26 no.4
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    • pp.343-351
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    • 2016
  • Objective: The purpose of this study was to help improve game performance and provide preliminary data to enhance the efficiency of the kick and stability of the support foot by comparing the kinematic characteristics of the repeated side kick (geodeupyeopchagi) in poomsaeKoryo between expert and non-expert groups. Method: The subjects were divided into 2 groups according to proficiency in Taekwondo, an expert group and a non-expert group (n = 7 in each group), to observe the repeated side-kick technique. Four video cameras were set at a speed of 60 frames/sec and exposure time of 1/500 sec to measure the kinematic factors of the 2 groups. The Kwon3D XPprogramas used to collect and analyze three-dimensional spatial coordinates. Ground reaction force data were obtained through a force plate with a 1.200-Hz frequency. An independent samplesttest was performed, and statistical significance was defined as .05. The SPSS 18.0 software was used to calculate the mean and standard deviation of the kinematic factors and to identify the difference between the experts and non-experts. Results: The angular displacement of the hip joint in both the expert and non-expert groups showed statistical significance on E1 and E4 of the left support foot and E5 of the right foot (p<.05). The angle displacement of the knee joint in both groups showed statistical significance on E4 of the left support foot, and E1 and E2 of the right foot (p<.05). The angular velocity of the lower leg in both groups showed no statistical significance on the left support foot but showed statistical significance on E2 and E6 of the right foot (p<.05). The angular velocity of the foot in both groups showed no statistical significance on the left support foot but showed statistical significance on E2 of the right foot (p<.05). The vertical ground reaction force in both groups showed statistical significance on E2 (p<.05). The center of pressure in all directions in both groups showed statistical significance (p<.5). Conclusion: While performing the repeated side kick (geodeupyeopchagi), the experts maintainedconsistency and stability of the angle of the support leg while the kick foot moved high and fast. On the other hand, the angle of the support foot of non-experts appeared inconsistent, and the kick foot was raised, relying on the support leg, resulting in unstable and inaccurate movement.

An Experimental Study on the Effect of Raw Ginseng, White Ginseng and Red Ginseng on Immune Response in Mice (수삼(水蔘)·백삼(白蔘)·홍삼(紅蔘)이 세포성면역반응(細布性免疫反應) 및 체액성면역반응(體液性免疫反應)에 미치는 영향(影響))

  • Oh, Yong Sung
    • Journal of Sasang Constitutional Medicine
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    • v.1 no.1
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    • pp.125-138
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    • 1989
  • In order to investigate the effect of Row ginseng (Ra. G.; from $K{\acute{u}}msan$ province, Korea), White ginseng (W.G.; from $K{\acute{u}}msan$ province, Korea), and Red ginseng (Re. G.; form $K{\acute{u}}msan$ province, Korea) on immune response, the author used ICR mice having a body weight of about 20g as experimental animals dividing them into four groups-Saline, Ra. G, W.G., Re. G group. Delayed type hypersensitivity(DTH) and rosette forming cells(RFC) for cell-mediated immune response, hemagglutinin(HA) titers, hemolysin (HL) titers for humoral immune response were measured at 24 hours after challenge, The results were summarized as follows: 1) DTH was increased in all of the treated group as compared with the Saline group, with statistical significance(W.G.> Re. G. > Ra. G.). 2) RFC was increased in all of the treated group as compared with the Saline group, with statistical significance(W.G. > Re. G. > Ra. G.). 3) HA titer was increased in all of the treated group as compared with the Saline group, with statistical significance (Re. G.> W. G.> Ra. G.). 4) HL titer was increased in all of the treated group as compared with the Saline group, with statistical significance (Re. G. > W. G.> Ra. G.). Through the experimental study in ICR mice, these findings suggest that Raw ginseng, White ginseng and Red ginseng enhance both cell-mediated and humoral immune response with statistical significance.

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A Clinical Study on the Correlation between Spine Deformity and Foot Abnormality (척추변형과 족부병변의 임상적 상관관계)

  • Choi, Hyun-Im;Park, Hung-Ki;Ju, Mu-Yeol
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.10 no.1
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    • pp.117-128
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    • 2004
  • I have processed all the data by using SPSS PC+. And my research process was investigated for 34 students on the Forward Bending Test, Foot Printer Test, Feedoscope Test, X-ray Test and so on. The object of this thesis is to study the correlation between spine deformity and foot abnormality in a theoretical and empirical method. The main results of this study were as follows: 1. There was statistical significance on the correlation between foot length and spine length. 2. Spinal curve is the smallest on the pes plannus group and the biggest on the pes cavus group without statistical significance. 3. Left lumbar curve is the smallest, and right thoracic spine curve is the biggest on the left foot pattern group with statistical significance. 4. On the foot weight bearing groups, there was statistical significance both of between left and right foot groups. 5. There was no statistical significance on the t-test analysis between left and right foot area according to spinal curve typology. But there was tendency that thoracic spine curve is bigger in the same side of the foot area and lumbar spine curve is bigger in the opposite side of foot area.

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