scholarly journals Application of Time Series Models in Business Research: Correlation, Association, Causation

2020 ◽  
Vol 12 (12) ◽  
pp. 4833
Author(s):  
Zabihollah Rezaee ◽  
Sara Aliabadi ◽  
Alireza Dorestani ◽  
Nick J. Rezaee
Keyword(s):  
Time Series ◽  
Granger Causality ◽  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Time Series Models ◽  
Spearman Correlation ◽  
Business Research ◽  
Association Analyses ◽  
Time Series Analyses

Time series models are used to determine relationships, spot patterns, and detect abnormalities and irregularities among data. We explore the application of time series analyses in business research by discussing the differences among correlation, association, and Granger causality and providing insight into their proper use in the sustainability literature. In statistics, two correlation coefficients are typically calculated. The first one is the Pearson correlation coefficient and the second is the Spearman correlation coefficient. In the commonly used correlation analysis (the Pearson and the Spearman correlation coefficients), the focus is primarily on the changes in two variables regardless of the effects of other variables. On the contrary, in association analyses, the researcher examines the relationship between two variables while holding the effects of other related variables constant (ceteris paribus). In the study of the causation, or the cause–effect relationship between two variables, researchers are concerned about the effect of variable X on variable Y. The difficulty of achieving the third condition of causation is believed to be the main reason that in business literature causations are rarely used. The difficulty of achieving a causal relationship between two variables has moved researchers toward a special form of causation called “Granger causality”. We offer practical examples for correlation, association, causation, and the Granger causality and discuss their main differences and show how the use of a linear regression is inappropriate when the true relationship is non-linear. Finally, we discuss the policy, practical, and educational implications of our study.

scholarly journals Methods of Estimating Correlation Coefficients in the Presence of Influential Outlier(s)

2021 ◽  
Vol 4 (3) ◽  
pp. 157-185
Author(s):  
Etaga H.O. ◽  
Okoro I. ◽  
Aforka K.F. ◽  
Ngonadi L.O.
Keyword(s):  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Pearson Correlation Coefficient ◽  
Spearman Correlation ◽  
Correlation Methods ◽  
Linear Relationships ◽  
Median Correlation ◽  
Standing Problem ◽  
Research Analysis

Correlation methods are indispensable in the study of the linear relationship between two variables. However, many researchers often adopt inappropriate correlation methods in the study of linear relationships which usually leads to unreliable results. Recurrently, most researchers ignorantly employ the Pearson method in a dataset that contained outliers, instead of more appropriate correlation methods such as Spearman, Kendall Tau, Median and Quadrant which might be suitable in the calculation of correlation coefficient in the presence of influential outliers. It is noted that the accuracy of estimation of correlation coefficients under outliers has been a long-standing problem for methodological researchers. This is due to low knowledge of correlation methods and their assumptions which have led to inappropriate application of correlation methods in research analysis. Five different methods of estimating correlation coefficients in the presence of influential outlier (contaminated data) were considered: Pearson Correlation Coefficient, Spearman Correlation Coefficient, Kendall Tau Correlation Coefficient, Median Correlation Coefficient and Quadrant Correlation Coefficient.

Single- versus multiple-item assessment of quality of life in patients with advanced cancer

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e20528-e20528
Author(s):  
S. H. Bush ◽  
H. A. Parsons ◽  
J. L. Palmer ◽  
R. Chacko ◽  
Z. Li ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Regression Analysis ◽  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Well Being ◽  
Pearson Correlation Coefficient ◽  
Spearman Correlation ◽  
Symptom Intensity

e20528 Background: The main objective of palliative cancer care is to improve quality of life (QOL). As multiple dimensions impact on the construct of QOL, multi-dimensional instruments are usually used in its measurement. These are time consuming and burdensome for repeated use. Recent authors have suggested that brief single-item global assessments can provide a reliable measure of QOL. We assessed the performance of the Edmonton Symptom Assessment System ‘feeling of well-being’ item (ESAS WB) using the Functional Assessment of Cancer Therapy - General (FACT-G) instrument as a gold standard. Methods: After obtaining IRB approval, we reviewed the data from 213 advanced cancer patients who had participated in six studies from March 2006 to June 2008 and determined the level of association between baseline ESAS WB and FACT-G total score and subscale domains (Physical (Pwb), Social/Family (Swb), Emotional (Ewb), and Functional (Fwb) Well-Being) and also the 9 ESAS symptom intensity scores using Spearman correlation coefficients. We also calculated the change between the baseline (T1) and second (T2) observations of ESAS WB and of FACT-G total score and determined their level of association using a Pearson correlation coefficient. In addition, we predicted the change in FACT-G as predicted by the change in ESAS WB score using regression analysis. Results: Mean age was 60 (SD 12) years and 48% were female. At T1, the Spearman correlation coefficient of ESAS WB and FACT-G was -0.48 (p<0.0001). Spearman correlation coefficients for ESAS WB and FACT-G subscale domains and ESAS symptom intensity scores were also highly significant (p<0.0001) for all physical and emotional symptoms (other than p=0.003 for nausea) except for FACT Swb (p=0.08). The Pearson correlation coefficient for difference between T1 and T2 in ESAS WB and FACT-G for 146 patients was -0.36 (p<0.0001). The regression analysis was highly significant (p<0.0001). The change in ESAS WB corresponding to FACT-G published minimally important difference (MID) was -0.24 for 3, -1.55 for 5, and -2.87 for 7, respectively. Conclusions: ESAS WB is a practical instrument for clinical use and best reflects the Pwb, Ewb and Fwb domains of FACT-G as compared to Swb. No significant financial relationships to disclose.

scholarly journals A Quantitative Comparison of Multispectral Refraction Topography and Autorefractometer in Young Adults

2021 ◽  
Vol 8 ◽  
Author(s):  
Yunru Liao ◽  
Zhenlan Yang ◽  
Zijing Li ◽  
Rui Zeng ◽  
Jing Wang ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
High Agreement ◽  
Intraclass Correlation Coefficients ◽  
Repeatability And Reproducibility ◽  
The Mean

Purpose: Purpose of this study is to evaluate the measuring consistency of central refraction between multispectral refraction topography (MRT) and autorefractometry.Methods: This was a descriptive cross-sectional study including subjects in Sun Yat-sen Memorial Hospital from September 1, 2020, to December 31, 2020, ages 20 to 35 years with a best corrected visual acuity of 20/20 or better. All patients underwent cycloplegia, and the refractive status was estimated with autorefractometer, experienced optometrist and MRT. We analyzed the central refraction of the autorefractometer and MRT. The repeatability and reproducibility of values measured using both devices were evaluated using intraclass correlation coefficients (ICCs).Results: A total of 145 subjects ages 20 to 35 (290 eyes) were enrolled. The mean central refraction of the autorefractometer was −4.69 ± 2.64 diopters (D) (range −9.50 to +4.75 D), while the mean central refraction of MRT was −4.49 ± 2.61 diopters (D) (range −8.79 to +5.02 D). Pearson correlation analysis revealed a high correlation between the two devices. The intraclass correlation coefficient (ICC) also showed high agreement. The intrarater and interrater ICC values of central refraction were more than 0.90 in both devices and conditions. At the same time, the mean central refraction of experienced optometrist was −4.74 ± 2.66 diopters (D) (range −9.50 to +4.75D). The intra-class correlation coefficient of central refraction measured by MRT and subjective refraction was 0.939.Conclusions: Results revealed that autorefractometry, experienced optometrist and MRT show high agreement in measuring central refraction. MRT could provide a potential objective method to assess peripheral refraction.

Evaluation of Cultural Intelligence in Staff of Industries, Mines and Trades Organizations - Case Study

2017 ◽  
pp. 429-438
Author(s):  
Mohammad Abdolshah ◽  
Baranak Geranfar ◽  
Eisa Akbari ◽  
Jalil Vaziri
Keyword(s):  
Organizational Culture ◽  
Correlation Coefficient ◽  
Cultural Intelligence ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Statistical Population ◽  
Key Competencies ◽  
The Relationship ◽  
Personnel Department

This article examines one of the key competencies of the 21st century known as cultural intelligence (CQ). This study investigates the relationship between CQ, organizational culture, and the effectiveness of staff in the industry, mine, and trade organizations of Semnan province in Iran. Using correlational analysis, the statistical population includes a total of 103 people from 141 employees based on personnel department documents. Three questionnaires were used to measure the variables and descriptive and deductive statistics were applied to evaluate and analyze the data. The Pearson correlation coefficient and multivariate regression were used in deductive statistics to obtain the results. The findings show there is a significant relationship between CQ, organizational culture, and effectiveness. Among four cultural intelligence factors, only the knowledge of CQ can predict the effectiveness. The calculated correlation coefficient indicates that the creativity factors and communication pattern have the highest correlation coefficients.

Assessing the Motor Status Score: A Scale for the Evaluation of Upper Limb Motor Outcomes in Patients after Stroke

2002 ◽  
Vol 16 (3) ◽  
pp. 283-289 ◽  
Author(s):  
Mark Ferraro ◽  
Jennifer Hogan Demaio ◽  
Jennifer Krol ◽  
Chris Trudell ◽  
Keren Rannekleiv ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Upper Limb ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Pearson Correlation Coefficient ◽  
Maximum Score ◽  
Intraclass Correlation Coefficients ◽  
Upper Extremity Impairment ◽  
Motor Outcomes

The Motor Status Scale (MSS) measures shoulder, elbow (maximum score = 40), wrist, hand, and finger movements (maximum score = 42), and expands the measurement of upper extremity impairment and disability provided by the Fugl-Meyer (FM) score. This work examines the interrater reliability and criterion validity of the MSS performed in patients admitted to a rehabilitation hospital 21 ± 4 days after stroke. Using the MSS and the FM, 7 occupational therapists masked to each other’s judgments, evaluated 12 consecutive patients with stroke. Two therapists evaluated 6 additional patients on consecutive days. Intraclass correlation coefficients were significant for each group of raters for the shoulder/elbow and for the wrist/hand (P < 0.0001); test-retest measures were also significant for the shoulder/elbow (Pearson correlation coefficient r = 0.99, P < 0.004) and for the wrist/hand (Pearson correlation coefficient r = 0.99, P < 0.003). The internal item consistency for the overall MSS was significant (Cronbach alpha = 0.98, P < 0.0001). Finally the correlation between the MSS and the FM (R 2 = 0.964) was significant (P < 0.0001). The MSS affords a reliable and valid assessment of upper limb impairment and disability following stroke.

scholarly journals Measurement of flow harmonics correlations with mean transverse momentum in lead–lead and proton–lead collisions at $$\sqrt{s_{\mathrm{NN}}} = 5.02~\hbox {TeV}$$ with the ATLAS detector

2019 ◽  
Vol 79 (12) ◽  
Author(s):  
G. Aad ◽  
◽  
B. Abbott ◽  
D. C. Abbott ◽  
A. Abed Abud ◽  
...  
Keyword(s):  
Charged Particle ◽  
Transverse Momentum ◽  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Gluon Plasma ◽  
Pearson Correlation Coefficient ◽  
Order Flow ◽  
Momentum Range ◽  
Ion Collisions

AbstractTo assess the properties of the quark–gluon plasma formed in ultrarelativistic ion collisions, the ATLAS experiment at the LHC measures a correlation between the mean transverse momentum and the flow harmonics. The analysis uses data samples of lead–lead and proton–lead collisions obtained at the centre-of-mass energy per nucleon pair of 5.02 TeV, corresponding to total integrated luminosities of $$22~\upmu \text {b}^{-1}$$22μb-1 and $$28~\text {nb}^{-1}$$28nb-1, respectively. The measurement is performed using a modified Pearson correlation coefficient with the charged-particle tracks on an event-by-event basis. The modified Pearson correlation coefficients for the 2nd-, 3rd-, and 4th-order flow harmonics are measured in the lead–lead collisions as a function of event centrality quantified as the number of charged particles or the number of nucleons participating in the collision. The measurements are performed for several intervals of the charged-particle transverse momentum. The correlation coefficients for all studied harmonics exhibit a strong centrality evolution, which only weakly depends on the charged-particle momentum range. In the proton–lead collisions, the modified Pearson correlation coefficient measured for the 2nd-order flow harmonics shows only weak centrality dependence. The lead-lead data is qualitatively described by the predictions based on the hydrodynamical model.

scholarly journals Validation of the pediatric Radboud dysarthria assessment

2021 ◽  
pp. 1-12
Author(s):  
Marieke Ruessink ◽  
Lenie van den Engel-Hoek ◽  
Marjo van Gerven ◽  
Bea Spek ◽  
Bert de Swart ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Intraclass Correlation ◽  
Self Care ◽  
Reliability And Validity ◽  
Correlation Coefficients ◽  
Activity Level ◽  
Clinical Use ◽  
Spearman Correlation ◽  
Rater Reliability ◽  
Video Recordings

PURPOSE: The Radboud Dysarthria Assessment (RDA) was published in 2014. Adaptation into a pediatric version (p-RDA) was required because of relevant differences between children and adults. The purpose of this study was to assess the feasibility of the p-RDA and to test intra-rater and inter-rater reliability as well as the validity of the two severity scales (function and activity level). METHODS: Video recordings were made of 35 participants with (suspected) dysarthria (age 4 to 17 years) while being assessed using the p-RDA. Intra-rater reliability was assessed by one, and inter-rater reliability by two experiments using the Intraclass Correlation Coefficient (ICC). Validity of the severity scales was tested by correlating the consensus scores with the independently rated scores on four communication scales, three mobility scales, and one self-care scale using Spearman correlation coefficients (r s). RESULTS: The assessment was applicable for 89% of the tested sample, with good intra-rater and inter-rater reliability (ICC = 0.88–0.98 and 0.83–0.93). The p-RDA severity scales (function and activity level) correlated from substantially to strongly with the communication scales (r s = 0.69–0.82 and 0.77–0.92) and self-care scale (r s = 0.76–0.71) and correlated substantially with the mobility scales (r s = 0.49–0.60). CONCLUSION: The feasibility, reliability and validity of the p-RDA are sufficient for clinical use.

scholarly journals The effect of education and sporting experience of iranian premier league football players on their awareness of sports law

2020 ◽  
Vol 13 (32) ◽  
pp. 1-15
Author(s):  
Mahdi Azimi ◽  
Seyed Amir Reza Hosseinipour Rafsanjani ◽  
Mona Torkaman
Keyword(s):  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Percent Level ◽  
Football Players ◽  
Pearson Correlation Coefficient ◽  
Spearman Correlation ◽  
Sports Law ◽  
Premier League ◽  
History Of ◽  
Kendall Correlation

The purpose of this study was to investigate the relationship between education and athletic background of Premier League football players on their awareness of sports Law. In this study, descriptive-analytical method and Spearman correlation coefficient were used. Ninety-five percent level was used as the criterion for rejecting the hypothesis. Questionnaires about variables were used to identify the sample group and the main questions about players' legal awareness were used for data collection. The results showed that Pearson correlation coefficient was 0.107, Spearman correlation coefficient was 0.204 and Kendall correlation coefficient was 0.139 and significant was 0.88. There is no relationship between awareness of sports law and the history of sports in the Premier League. Pearson correlation coefficient of 0.388, Spearman correlation coefficient of 0.204 and Kendall correlation coefficient of 0.139 and significant value of 0.001 indicated that there is a relationship between sport legal awareness and education of the Iranian Premier League players.

scholarly journals MONITORING OF TIME-SERIES SOIL MOISTURE BASED ON ADVANCED DINSAR

2021 ◽  
Vol V-3-2021 ◽  
pp. 51-55
Author(s):  
C. H. Yang ◽  
A. Müterthies
Keyword(s):  
Time Series ◽  
Soil Moisture ◽  
Water Content ◽  
Large Scale ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Organic Soil ◽  
Underground Water ◽  
Multi Temporal ◽  
Mean Square Errors

Abstract. Understanding soil moisture is essential for earth and environmental sciences especially in geology, hydrology, and meteorology. Remote sensing techniques are widely applied to large-scale monitoring tasks. Among them, DInSAR using multi-temporal spaceborne SAR images is able to derive surface movement up to mm level over an area. One of the factors inducing the movement is variation of soil moisture. Based on this, a semi-empirical approach can be tailored to retrieve the underground water content. However, the derived movement is often contaminated with other irrelevant noise. Besides, a time-series analysis could not be simply implemented without additional fusion and calibration. In this paper, we propose a novel modelling based on advanced DInSAR to solve these problems. The irrelevant noise will be removed as parts of the modelled elements in the DInSAR processing. A forward model on a scene is built by regressing the measured soil moisture on the DInSAR-derived movement series. We tested our approach using Sentinel-1 images in the grasslands of organic soil within State of Brandenburg, Germany. The Pearson correlation coefficients between the measured soil moistures and the DInSAR-derived movements are up to 0.91. The mean square errors of the predicted soil moistures compared with the measurements reach 3.03 % (volumetric water content) at best. Our study shows a promising new concept to develop a global monitoring of soil moisture in the future.

scholarly journals Investigation of the Relationship between Trauma, Anxiety, Depression and Stress in Kerman Emergency Medical and Emergency Center 115

2020 ◽  
pp. 25-31 ◽  
Author(s):  
Mohammadreza Soltaninejad ◽  
Mohsen Aminizadeh ◽  
Amin Saberinia
Keyword(s):  
Mental Health ◽  
Correlation Coefficient ◽  
Correlation Coefficients ◽  
Spearman Correlation ◽  
Emergency Center ◽  
Statistical Population ◽  
Emergency Medical ◽  
Spss Software ◽  
Anxiety Depression ◽  
The Relationship

Introduction: The efficacy of psychological and pharmacological approaches is broadly similar in the acute treatment of psychopharmacology disorders. One of the most important stressful environmental stimuli that can cause chronic stress is people's jobs. And since promoting the mental health of individuals in a society, especially its constituent classes, is essential to the dynamics and growth of that society, this research was conducted with the aim of investigating the relationship between trauma caused by accident and anxiety, depression, and stress in Kerman Emergency Medical and Emergency Center during 2019. Methods: This is a descriptive-correlational study. The statistical population was all 70 personnel members of Emergency Medical and 115 Emergency Centers in Kerman. The Depression, Stress and Anxiety Scale 21 and Trauma Screening were used as the instruments of measurement. Pearson and Spearman correlation coefficients through SPSS software were used to test the hypotheses. Results: There is a significant and direct correlation between trauma caused by accidents and personnel anxiety with a correlation coefficient of 0.407. Also, there is a significant and direct correlation between trauma caused by accidents and personnel depression with a correlation coefficient of 0.407. There is also a significant and direct relationship between trauma caused by accidents and personnel stress with a correlation coefficient of 0.388. Conclusion: Our data suggested that mental health along with personality traits is a solution to reduce stress and anxiety resulting from the personnel facing trauma caused by accidents.

Sign in / Sign up

Export Citation Format

Share Document