Decline of Pearson’s r with categorization of variables: a large-scale simulation

AbstractWe systematically investigated an ongoing debate about the possible correlation between SARS-CoV-2 (COVID-19) epidemiological outcomes and solar exposure in European countries, in the period of March – August 2020. For each country, we correlated its mortality data with solar insolation (watt/square metre) and objective sky cloudiness (as cloud fraction) derived from satellite weather data. We found a positive correlation between the monthly mortality rate and the overall cloudiness in that month (Pearson’s r(35)=.779, P<.001; linear model fitting the data, adjusted R2 =0.59). In Europe, in colder months, approximately 34% to 58% of the variance in COVID-19 mortality/million appears to be predicted by the cloudiness fraction of the sky, except in August in which only ∼15% of the variance was explained. The data show a low, negative correlation between the mortality rate with the overall insolation received by the country area in that entire month (Pearson’s r(35)=-0.622, P<.001). Additionally, we did not find any statistically significant correlation between the mortality and the latitude of the countries when the “latitude of a country” was precisely defined as the average landmass location (country centroid). The unexpected correlation found between cloudiness and mortality could perhaps be explained by the following: 1) heavy cloudiness is linked with colder outdoor surfaces, which might aid virus survival; 2) reduced evaporation rate; 3) moderate pollution may be linked to both cloudiness and mortality; and 4) large-scale behavioural changes due to cloudiness (which perhaps drives people to spend more time indoors and thus facilitates indoor contamination).

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Farmers Education and Risk Perceptions of Large-Scale Mining in Ghana

Current World Environment ◽

10.12944/cwe.15.special-issue1.04 ◽

2020 ◽

Vol Special Issue (1) ◽

Author(s):

Fred Owusu-Ansah

Keyword(s):

Risk Perceptions ◽

Large Scale ◽

Social Protection ◽

Natural Capital ◽

Economic Status ◽

Empirical Studies ◽

Pearson's R ◽

Mining Project ◽

Mining Projects ◽

Pearson’S R

Empirical studies that use household farmers as unit of analysis to examine the relative influence of education on risk perceptions of large scale mining projects in Ghana are virtually absent. This study combined evidence from literature, mixed methods, Pearson’s Chi square (X2) and correlation analyses. Systematic random sampling was used in selecting farmers. Data obtained from 725 households was analyzed using SPSS. The hypothesis “education has no relationship with farmers’ risk perceptions of large-scale mining projects in Ghana” was tested. Results revealed that large-scale mining has both positive and negative image in the minds of farmers. Farmers’ education strongly correlated with their knowledge of the state of the environment and natural resources before the arrival of the mining project [Pearson’s (X2) = 26.743; p = 0.024; Pearson's (r) = 0.791; p = 0.010]. Statistical evidence exists to support the claim that local communities protested against the mining project due to their ability to anticipate adverse effects of the project on environmental quality. Education significantly influenced farmers’ ability to link sources of livelihood to environmental and resource protection [Pearson's (X2) = 25.516, p = 0.043; Pearson's (r) = 0.640; p = 0.036]. Farmers’ risk perceptions of large scale mining as a threat to: community’s natural capital; traditional systems; environmental and social protection regime; established administrative procedures and good conducts of public officials; as well as being a threat to rural livelihood have serious implications for achieving the goals of sustainable mining in Ghana. Nonetheless, farmers associated mining as agent of economic development, and education significantly influenced this assessment [Pearson’s (X2) = 28.093, p = 0.021; Pearson’s (r) = 0.077; p = 0.041]. This paper concludes that education is a significant predictor in risk perception assessment. Robust environmental and social protection regimes, strong public institutions and improved socio-economic status are good predictors of farmers’ risk perceptions of mining.

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CODEM Instrument

GeroPsych ◽

10.1024/1662-9647/a000100 ◽

2014 ◽

Vol 27 (1) ◽

pp. 23-31 ◽

Cited By ~ 4

Author(s):

Anne Kuemmel (This author contributed eq ◽

Julia Haberstroh (This author contributed ◽

Johannes Pantel

Keyword(s):

Convergent Validity ◽

Interrater Reliability ◽

Discriminant Validity ◽

Assessment Tool ◽

Intraclass Correlation ◽

Well Being ◽

Communication Behavior ◽

People With Dementia ◽

Pearson's R ◽

Pearson’S R

Communication and communication behaviors in situational contexts are essential conditions for well-being and quality of life in people with dementia. Measuring methods, however, are limited. The CODEM instrument, a standardized observational communication behavior assessment tool, was developed and evaluated on the basis of the current state of research in dementia care and social-communicative behavior. Initially, interrater reliability was examined by means of videoratings (N = 10 people with dementia). Thereupon, six caregivers in six German nursing homes observed 69 residents suffering from dementia and used CODEM to rate their communication behavior. The interrater reliability of CODEM was excellent (mean κ = .79; intraclass correlation = .91). Statistical analysis indicated that CODEM had excellent internal consistency (Cronbach’s α = .95). CODEM also showed excellent convergent validity (Pearson’s R = .88) as well as discriminant validity (Pearson’s R = .63). Confirmatory factor analysis verified the two-factor solution of verbal/content aspects and nonverbal/relationship aspects. With regard to the severity of the disease, the content and relational aspects of communication exhibited different trends. CODEM proved to be a reliable, valid, and sensitive assessment tool for examining communication behavior in the field of dementia. CODEM also provides researchers a feasible examination tool for measuring effects of psychosocial intervention studies that strive to improve communication behavior and well-being in dementia.

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LARGE-SCALE SIMULATION OF OIL RECOVERY BY SURFACTANT-POLYMER FLOODING

Eurasian Journal of Mathematical and Computer Applications ◽

10.32523/2306-6172-2016-4-1-12-31 ◽

2016 ◽

Vol 4 (1) ◽

pp. 12-31 ◽

Cited By ~ 1

Author(s):

D.Zh. Akhmed-Zaki ◽

T.S. Imankulov ◽

B. Matkerim ◽

B.S. Daribayev ◽

K.A. Aidarov ◽

...

Keyword(s):

Oil Recovery ◽

Large Scale ◽

Polymer Flooding ◽

Large Scale Simulation

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LARGE-SCALE SIMULATION OF THE CZOCHRALSKI GROWTH OF SILICON CRYSTALS

Proceeding of International Heat Transfer Conference 10 ◽

10.1615/ihtc10.1820 ◽

1994 ◽

Cited By ~ 1

Author(s):

R. A. Brown ◽

T. A. Kinney ◽

W. Zhou ◽

D. E. Bornside

Keyword(s):

Large Scale ◽

Czochralski Growth ◽

Large Scale Simulation ◽

Silicon Crystals

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Pre-Planned and Non-Planned Agility in Patients Ongoing Rehabilitation after Knee Surgery: Design, Reliability and Validity of the Newly Developed Testing Protocols

Diagnostics ◽

10.3390/diagnostics11010146 ◽

2021 ◽

Vol 11 (1) ◽

pp. 146

Author(s):

Ivan Peric ◽

Miodrag Spasic ◽

Dario Novak ◽

Sergej Ostojic ◽

Damir Sekulic

Keyword(s):

Total Knee Arthroplasty ◽

Body Mass ◽

Knee Arthroplasty ◽

Arthroscopic Surgery ◽

The Body ◽

Clinical Population ◽

Pearson's R ◽

Total Knee ◽

Type Of Surgery ◽

Pearson’S R

Background: Due to its association with the risk of falling and consequent injury, the importance of agility is widely recognized, but no study so far has examined the different facets of agility in an untrained/clinical population. The aim of this study was to evaluate the reliability, validity, and correlates of newly developed tests of non-planned agility (NPA) and pre-planned agility (PPA) in an untrained/clinical sample. Methods: The sample comprised 38 participants older than 40 years (22 females, age: 56.1 ± 17.3 years, height: 170.4 ± 10.8 cm, mass: 82.54 ± 14.79 kg) who were involved in a rehabilitation program following total knee arthroplasty and knee arthroscopy. Variables included age, gender, type of surgery, history of fall, anthropometrics/body composition, and newly developed tests of NPA and PPA. Results: The results showed the high inter-testing- (ICC > 0.95, CV < 9%), and intra-testing-reliability (ICC > 0.96, CV < 9) of the newly developed tests. PPA and NPA were found to be valid in differentiation between age groups (>50 yrs. vs. <50 yrs.), and genders, with better performance in younger participants and males. Only NPA differentiated participants according to type of surgery, with better performance in those who had arthroscopic surgery, than those who had total knee arthroplasty. No differences in NPA and PPA were established between groups based on fall-history. In females, the body mass (Pearson’s r = 0.58 and 0.59, p < 0.001) and body fatness (Pearson’s r = 0.64 and 0.66, p < 0.001) were negatively correlated, while the lean body mass (Pearson’s r = 0.70 and 0.68, p < 0.001) was positively correlated with PPA and NPA. The NPA and PPA were highly correlated (Pearson’s r = 0.98, p < 0.001). Conclusions: We found that the proposed tests are reliable when evaluating agility characteristics in an untrained/clinical population after knee arthroplasty/arthroscopy. Further evaluation of the specific validity of the proposed tests in other specific subsamples is warranted.

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