• Title/Summary/Keyword: Spearman Rank Correlation Coefficient

Search Result 94, Processing Time 0.02 seconds

Maximum Sunspot Numbers and Active Days

  • Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
    • /
    • v.30 no.3
    • /
    • pp.163-168
    • /
    • 2013
  • Parameters associated with solar minimum have been studied to relate them to solar activity at solar maximum so that one could possibly predict behaviors of an upcoming solar cycle. The number of active days has been known as a reliable indicator of solar activity around solar minimum. Active days are days with sunspots reported on the solar disk. In this work, we have explored the relationship between the sunspot numbers at solar maximum and the characteristics of the monthly number of active days. Specifically, we have statistically examined how the maximum monthly sunspot number of a given solar cycle is correlated with the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days for the corresponding solar cycle. We have calculated the linear correlation coefficient r and the Spearman rank-order correlation coefficient $r_s$ for data sets prepared under various conditions. Even though marginal correlations are found, they turn out to be insufficiently significant (r ~ 0.3). Nonetheless, we have confirmed that the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days is less steep when solar cycles belonging to the "Modern Maximum" are considered compared with rests of solar cycles. We conclude, therefore, that the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days is indeed dependent on the solar activity at its maxima, but that this simple relationship should be insufficient as a valid method to predict the following solar activity amplitude.

Distributions of the GSTM1 and GSTT1 Null Genotypes Worldwide are Characterized by Latitudinal Clines

  • Saitou, Marie;Ishida, Takafumi
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.1
    • /
    • pp.355-361
    • /
    • 2015
  • Background: Deletion types of genetic variants of glutathione S-transferase (GST) M1 and T1, the GSTM1 null and GSTT1 null which are risk factors for certain cancers, have been ubiquitously found in human populations but their worldwide distribution pattern is unclear. Materials and Methods: To perform a meta-analysis, a systematic search for the literature on GSTM1 and GSTT1 null genotypes was done to identify 63 reports for 81 human populations. Relationships between the GSTM1 and GSTT1 null genotype frequencies and the absolute latitude of 81 populations were tested by Spearman's rank correlation coefficient. Results: A significant positive correlation was detected between the GSTM1 null genotype frequency and the absolute latitude (r=0.28, p-value <0.05), whereas the GSTT1 null genotype frequency and absolute latitude showed a significant negative correlation (r= -0.41 p-value <0.01). There was no correlation between the frequencies of GSTM1 and GSTT1 null genotype in each population (r= -0.029, p-value=0.80). Conclusions: Latitudinal clines of the distribution of the GSTM1 and GSTT1 null genotypes may be attributed to the result of gene-environmental adaptation. No functional compensation between GSTM1 and GSTT1 was suggested by the lack of correlation between the null frequencies for GSTM1 and GSTT1.

Study on the correlation between the soil bacterial community and growth characteristics of wild-simulated ginseng(Panax ginseng C.A. Meyer) (토양세균군집과 산양삼 생육특성 간의 상관관계 연구)

  • Kim, Kiyoon;Um, Yurry;Jeong, Dae Hui;Kim, Hyun-Jun;Kim, Mahn Jo;Jeon, Kwon Seok
    • Korean Journal of Environmental Biology
    • /
    • v.37 no.3
    • /
    • pp.380-388
    • /
    • 2019
  • The studies regarding soil bacterial community and correlation analysis of wild-simulated ginseng cultivation area are insufficient. The purpose of this study was to investigate the correlation between soil bacterial community and growth characteristics of wild-simulated ginseng for selection of suitable cultivation area. The bacterial community was investigated by high throughput sequencing technique (Illumina platform). The correlation coefficient between soil bacterial community and growth characteristics were analyzed using Spearman's rank correlation. The soil bacterial community from soil samples of 8 different wild-simulated ginseng cultivated area exhibited two distinct clusters, cluster 1 and cluster 2. The relative abundance of Proteobacteria (35.4%) and Alphaproteobacteria(24.4%) was observed to be highest in all soil samples. The lower soil pH and higher abundance of Acidobacteria resulted in increased growth of wild-simulated ginseng. Additionally, abundance of Acidobacteriia (class) and Koribacteraceae (family) demonstrated significant positive correlation with fresh weight of wild-simulated ginseng. The results of this study clearly state the correlation between growth characteristic and soil bacterial community of wild-simulated ginseng cultivation area, thereby offering effective insight into selection of suitable cultivation area of wild-simulated ginseng.

Evaluation of Ecological Niche for Major Tree Species in the Natural Deciduous Forest of Mt. Chumbong (점봉산(點鳳山) 일대(一帶) 천연활엽수림(天然闊葉樹林)의 주요(主要) 구성(構成) 수종(樹種)에 대한 생태지위(生態地位) 평가(評價))

  • Kim, Guang Ze;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
    • /
    • v.90 no.3
    • /
    • pp.380-387
    • /
    • 2001
  • The characteristics of ecological niche, breadth and overlap, for seventeen major tree species were evaluated in the natural deciduous forest in Mt. Chumbong area. Employed by the plot sampling method, the environmental gradient for vertical niche was based on the intensity of light within the forest, and that for horizontal niche was based on multi-dimensional resources in distribution pattern. The result showed that Fraxinus rhynchophylla had the highest value of vertical niche breadth and Maackia amurensis had the lowest, and Acer pseudo-sieboldianum had the highest value of horizontal niche breadth and Betula costata had the lowest. There was no significant correlation between both measures of niche breadth. However, the tolerance index for each species was positively correlated to the values of niche breadth. Spearman's rank correlation coefficients were applied to test the correlationship between the species ranks of tolerance index and those of two ecological niche breadths. The coefficient of $r_s=0.432$ ($P{\leq}0.1$) was not enough to support significant correlationship between the tolerance index and vertical niche breadth at the 95% probability. If Carpinus cordata, rarely reach canopy of the forest due to its own growth form, are excluded from the analysis, coefficient was calculated as $r_s=0.650$ ($P{\leq}0.01$), resulting in highly significant correlationship. The Spearman's rank correlation coefficient was $r_s=0.797$ ($P{\leq}0.01$) for tolerance indices and the values of horizontal niche breadth, indicating highly significant. Four distinctive species groups, produced by cluster analysis on the basis of ecological niche overlap for each pair of species, were in considerable accord with the positively associated species constellation pattern created by the inter-species association analysis.

  • PDF

A study on the determination of an optimal handle diameter for a signal billy (신호봉 손잡이의 최적 굵기 결정에 관한 연구)

  • 변승남;이동훈
    • Journal of the Ergonomics Society of Korea
    • /
    • v.16 no.1
    • /
    • pp.15-27
    • /
    • 1997
  • The objectives of this study were twofold; (1) to determine an optimal handle size of a signal billy, based on the subjective assessment of grip comfort and (2) to investigate the relationship between hand anthropometry and the optimal handle size. Thirty-seven university male students were asked to rate seven cylindrical handles of different diameters in barehanded and gloved conditions, respectively. Among these handles, 3.5cm diameter of the handle size was found to be the most comfortable, in both bardhanded and gloved conditionsl. However, no statistically significant reduction in grip comfort occurred within handle diameter ranging from 2.5cm to 4.0cm. As the handle diameter was deivated from the range, grip discomfort in creased significantly. A Spearman rank correlation coefficient test revealed that hand anthropometries such as finger lengths, hand circumference, and hand thickness were statistically significant factors on the determination of the optimal handle size. The implications of these findings were discussed. The results of this study can be used as guidelines in designing the hand tools for power grip.

  • PDF

The Effect of an Alcohol Education Program on Behavior Related Drinking by the Elderly with Drinking Problems (알코올 교육 프로그램이 음주문제를 가진 노인의 음주관련 지식과 행동에 미치는 효과)

  • Oh, Suk-Hee;Sun, Jung-Joo
    • Journal of Korean Public Health Nursing
    • /
    • v.23 no.1
    • /
    • pp.17-26
    • /
    • 2009
  • Purpose: In this study, the effects of an alcohol education program for elderly persons with drinking problems and the effects of knowledge of the behavior associated with alcohol use by elderly individuals with drinking problems were evaluated. Method: A single-group repeated study was conducted to evaluate 19 elderly individuals with drinking problems who used the G-city Elderly Welfare Center, with more than eight points in AUDIT results. The changes in drinking knowledge and alcohol behavior following an alcohol education program were evaluated. The effectiveness of the program was analyzed by a Wilcoxon signed rank test. and the relationship between drinking knowledge and changes in alcohol behavior was measured by Spearman's rank correlation coefficient. Results: The results indicated that drinking knowledge after conducting education increased significantly(Z=-3.826, p<.001), and that this increased knowledge resulted in significant changes in alcohol behavior(Z=-3.830, p<.001). There was a significantly positive relationship between drinking knowledge and changes in alcohol behavior(r=.464, p=0.013). Conclusion: Alcohol education programs effectively educate the elderly with drinking problems regarding alcohol, which influences their alcohol behavior.

Intravoxel Incoherent Motion Magnetic Resonance Imaging for Assessing Parotid Gland Tumors: Correlation and Comparison with Arterial Spin Labeling Imaging

  • Gao Ma;Xiao-Quan Xu;Liu-Ning Zhu;Jia-Suo Jiang;Guo-Yi Su;Hao Hu;Shou-Shan Bu;Fei-Yun Wu
    • Korean Journal of Radiology
    • /
    • v.22 no.2
    • /
    • pp.243-252
    • /
    • 2021
  • Objective: To compare and correlate the findings of intravoxel incoherent motion (IVIM) magnetic resonance (MR) imaging and arterial spin labeling (ASL) imaging in characterizing parotid gland tumors. Materials and Methods: We retrospectively reviewed 56 patients with parotid gland tumors evaluated by MR imaging. The true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and fraction of perfusion (f) values of IVIM imaging and tumor-to-parotid gland signal intensity ratio (SIR) on ASL imaging were calculated. Spearman rank correlation coefficient, chi-squared, Mann-Whitney U, and Kruskal-Wallis tests with the post-hoc Dunn-Bonferroni method and receiver operating characteristic curve assessments were used for statistical analysis. Results: Malignant parotid gland tumors showed significantly lower D than benign tumors (p = 0.019). Within subgroup analyses, pleomorphic adenomas (PAs) showed significantly higher D than malignant tumors (MTs) and Warthin's tumors (WTs) (p < 0.001). The D* of WTs was significantly higher than that of PAs (p = 0.031). The f and SIR on ASL imaging of WTs were significantly higher than those of MTs and PAs (p < 0.05). Significantly positive correlation was found between SIR on ASL imaging and f (r = 0.446, p = 0.001). In comparison with f, SIR on ASL imaging showed a higher area under curve (0.853 vs. 0.891) in discriminating MTs from WTs, although the difference was not significant (p = 0.720). Conclusion: IVIM and ASL imaging could help differentiate parotid gland tumors. SIR on ASL imaging showed a significantly positive correlation with f. ASL imaging might hold potential to improve the ability to discriminate MTs from WTs.

General Population Time Trade-off Values for 42 EQ-5D Health States in South Korea (시간교환법을 이용한 일부 EQ-5D 건강상태의 질 가중치 측정)

  • Jo, Min-Woo;Lee, Sang-Il
    • Journal of Preventive Medicine and Public Health
    • /
    • v.40 no.2
    • /
    • pp.169-176
    • /
    • 2007
  • Objectives : This study was conducted to elicit quality weights for 42 EQ-5D health states with the time trade-off (TTO) method from the general population of South Korea. Methods : We selected the same EQ-5D health states as those in the UK MVH study. The Korean version of EQ-5D questionnaire and TTO method were used for the valuation process. We interviewed 500 people as a representative sample of the general population in Seoul and Gyeonggido. The result was compared with those from UK, Japan, and USA by Spearman's rank correlation and t-test. Results : TTO values for 42 EQ-5D health states and 'unconscious' state were obtained from the general South Korean population. The best one was '11112' state and the worst one was 'unconscious' state. The states worse than death were '33323', '33333', and 'unconscious' states, which had negative TTO values. There was a strong correlation between TTO values of the EQ-5D health states and those of their corresponding states from UK, Japan, and USA (Spearman's correlation coefficient: 0.885, 0.882, and 0.944, respectively, p <0.001). However, absolute TTO values of most EQ-5D health states were significantly different from those of their corresponding states in other foreign studies (UK : 41/42, USA : 32/42, Japan : 15/17). Conclusions : We found that the Korean general population TTO values for EQ-5D health states were different from those of other foreign studies, suggesting that a specific Korean valuation set should be developed and used for economic evaluation studies in South Korea.

Correlation Between Apoptosis and Intratumoral Microvessel Density in Non-Small Cell Lung Cancer. (비소세포 폐암에서 아포프토시스와 종양내 미세 혈관 밀도의 관계)

  • 장인석;김종우;김진국;한정호
    • Journal of Chest Surgery
    • /
    • v.32 no.2
    • /
    • pp.151-157
    • /
    • 1999
  • Background: Increasing evidences from experimental studies indicate that apoptosis may be inversely related to angiogenesis in tumor progression. Material and Method: To explore how apoptosis correlates with tumor angiogenesis, we measured the apoptotic index(AI) using the terminal deoxynucleotidyl transferase method(Apop Tag In Situ Apoptosis Detection Kit, ONCOR) and the intratumoral microvessel density using the anti-CD31 monoclonal antibody in non-small cell lung cancer. Result: Statistical analysis revealed an inverse correlation between AIs and intratumoral microvessel densities in squamous cell lung carcinoma(Spearman rank correlation coefficient r=- 0.229, p=0.047). Conclusion: The results of this study demonstrated that the amount of apoptosis in squamous cell lung carcinoma may be influenced by the extent of neovascularization. This suggests that tumor angiogenesis may contribute to a reduction of apoptosis in tumor cells.

  • PDF

The Relationship between Functional Movement Screen and Ankle Dysfunctions with Chronic Ankle Instability

  • Choi, Ho-Suk;Shin, Won-Seob;Shim, Jae-Kwang;Choi, Sung-Jin;Bang, Dae-Hyouk
    • The Journal of Korean Physical Therapy
    • /
    • v.26 no.6
    • /
    • pp.459-463
    • /
    • 2014
  • Purpose: The purpose of this study was to investigate the correlations between functional movement screen (FMS) and ankle dysfunctions in subjects with chronic ankle instability (CAI). Methods: This study was a cross-sectional study of 20 participants with CAI. The ankle dorsiflexion range of motion (ROM), Foot and Ankle Disability Index (FADI), center of pressure (COP) path length, and COP velocity for ankle dysfunction were measured in all the subjects. All the subjects underwent the FMS concerned with ankle functions consisted of deep squats, hurdle steps and in-line lunges. The Spearman rank-order correlation coefficient was used to determine relationship between the ankle ROM, FADI, COP and FMS. Results: The results of the deep squat and in-line lunge exercises revealed a significant correlation with the ankle dorsiflexion ROM, FADI, COP path length, and COP velocity. The hurdle step showed no correlation with the ankle dorsiflexion ROM and FADI but a significant relationship with the COP path length and COP velocity. Conclusion: The results of this study showed that relationship deep squat and in-line lunge and it is suggested that an assessment tool using ankle dorsiflexion ROM and ankle instability would be clinically effective.