scholarly journals Multivariate Time Series Modelling with Seasonal Univariate Components; Evidence from Nigeria GDP

2019 ◽  
pp. 1-20
Author(s):  
Taofikat Abidemi Azeez ◽  
Yusuf Olufemi Olusola ◽  
Hamzat Kayode Idris ◽  
Salawu Monsuru Micheal
Keyword(s):  
Time Series ◽  
Multivariate Time Series ◽  
Positive Association ◽  
Information Criteria ◽  
Strong Positive Correlation ◽  
Positive Correlation ◽  
Pairwise Correlation ◽  
Time Series Modelling ◽  
Adf Test ◽  
Time Plot

The patterns of GDP variables are graphically examined using time plot presented the time plot for the GDP variables concerning time presented a combined single time plot for all the considered GDP variables. The relationship, as well as the degree of relationship between/among the GDP variables, was further revealed by computing the pairwise correlation. Based on the output, each variable when crossed classified with itself have a strong positive correlation with an output of (1), while pairwise correlation reveals a positive figure with the least estimate being (0.3149), this implies that for all the variables there exist a positive correlation. All the pairwise relationship reveals a strong positive association with all the estimates revealing a value between (0.8-0.9) except ‘trade and industry' that shows a positive relationship but not strong with an estimate of (0.3149). The initial test in fitting a time series model is to examine the series for stationarity. The Augmented Dickey-Fuller test revealed that ‘Agriculture’, ‘Construction’, and Services’” satisfies the requirement of stationarity while the series ‘industry and “Trade” are non-stationary initially but later became stationary after the application of the first difference transformation which was confirmed after the application of the ADF test to the first differenced series. The Johansen co-integration's Trace test was employed to determine the order of co-integration and it was revealed that the series are cointegrated hence presentation of the equation of integration. We presented the lag length estimation criteria which revealed that the lag length of order 5 is appropriate for the VAR model as suggested by Akaike Information Criteria (AIC), Hannan-Quinn (HQ) Information Criteria, Schwarz Information Criteria (SC). The VAR(5) model was fitted for all the considered GDP variables.

scholarly journals Correlation between salivary glucose and blood glucose levels in diabetic and non-diabetic individuals

2019 ◽  
Vol 6 (4) ◽  
pp. 1220
Author(s):  
Uma Maheswara R. Golamari ◽  
Meenakshi Sundari Subramaniyan Natarajan ◽  
Annam Lakshmanan ◽  
Rajeswari K. Balakrishnan
Keyword(s):  
Blood Glucose ◽  
Blood Sugar ◽  
Positive Association ◽  
Fasting Blood Sugar ◽  
Diabetic Patients ◽  
Strong Positive Correlation ◽  
Positive Correlation ◽  
Glucose Levels ◽  
Diabetic Population ◽  
Strong Positive Association

Background:  The aim of this study was to determine as well as to compare the salivary glucose levels in the diabetic and non-diabetic population and correlate the values with their fasting blood glucose and HbA1c (glycated Haemoglobin) levels. Many researchers have proposed the possibility of using salivary glucose estimation for screening and monitoring of effect in general population and in resource poor settings. But studies on this subject in Indian population are limited.Methods: The current study was an analytical cross sectional study of a group of 100 diabetic patients and 100 healthy controls, conducted in the Department of General Medicine, SRM medical college hospital. The mean difference in the salivary glucose between diabetic and non-diabetic population was compared using unpaired t-test.Results: There was a strong positive association between FBS (fasting blood sugar) and salivary glucose in the overall population. There was a strong positive correlation between FBS and Salivary glucose in FBS <200. There was a moderate positive association between FBS and salivary glucose in people with FBS value between 200 to 300 mg/dl. There was a weak positive association between FBS and salivary glucose in people with FBS value >300 mg/dl, which was statistically not significant. There was a strong positive correlation between HbA1c and salivary glucose in the overall population.Conclusions: There appears to be a strong positive association between fasting blood sugar and salivary glucose value in both study groups. But the correlation seems to be relatively weak in fasting blood sugar range above 300 mg/dl. Considering this positive association, further studies are needed to explore the possibility of utilizing salivary glucose for monitoring glycemic control.

Application of Interrupted Time Series Modelling to Prime Motor Spirit Distribution in Nigeria

2017 ◽  
Vol 7 (8) ◽  
pp. 46
Author(s):  
Ette Harrison Etuk ◽  
Imo Udo Moffat ◽  
Azubuike Samuel Agbam
Keyword(s):  
Time Series ◽  
Oil Industry ◽  
Interrupted Time Series ◽  
Intervention Model ◽  
Post Intervention ◽  
Abrupt Jump ◽  
Time Series Modelling ◽  
And Control ◽  
The Impact ◽  
Time Plot

An inspection of the time-plot of monthly Prime Motor Spirit (PMS) distribution in Nigeria from 2009 to 2015 reveals an abrupt jump in January 2013 with the series continuing at that level till 2015. Clearly the trend of the series was interrupted in January 2013 and it is believed that this perturbation was due to the deregulation of the downstream sector of the crude oil industry.  A t-test comparison of the pre- and the post-intervention means is highly significant (p < 0.0001) indicating the impact of the intervention. A model of the ARIMA family was to be fitted to the pre-intervention data which were observed to have a downward trend and be non-stationary. Differencing once rendered it stationary. An adequate ARIMA(2,1,0) model was fitted to the original pre-intervention series. Post-intervention forecasts were obtained on the basis of this model. These forecasts were subtracted from their respective post-intervention counterpart observations. These differences were modelled to obtain the transfer function of the intervention. The resultant intervention model closely fits the post-intervention data and may be used to explain and control the situation.

scholarly journals Count Data Time Series Modelling in Julia—The CountTimeSeries.jl Package and Applications

Entropy ◽  
2021 ◽  
Vol 23 (6) ◽  
pp. 666
Author(s):  
Manuel Stapper
Keyword(s):  
Time Series ◽  
Real Life ◽  
Theoretical Background ◽  
Information Criteria ◽  
Finite Sample ◽  
Ml Estimation ◽  
Real Life Data ◽  
Time Series Modelling ◽  
Finite Sample Properties ◽  
Count Data Time Series

A new software package for the Julia language, CountTimeSeries.jl, is under review, which provides likelihood based methods for integer-valued time series. The package’s functionalities are showcased in a simulation study on finite sample properties of Maximum Likelihood (ML) estimation and three real-life data applications. First, the number of newly infected COVID-19 patients is predicted. Then, previous findings on the need for overdispersion and zero inflation are reviewed in an application on animal submissions in New Zealand. Further, information criteria are used for model selection to investigate patterns in corporate insolvencies in Rhineland-Palatinate. Theoretical background and implementation details are described, and complete code for all applications is provided online. The CountTimeSeries package is available at the general Julia package registry.

Assessment of Correlation between Clinical Parameters and Pulp Canal Pathogens in Endodontic Pathologies: A Microbiological Study

2016 ◽  
Vol 17 (8) ◽  
pp. 654-658 ◽  
Author(s):  
Vinisha Pandey ◽  
Isha Choudhary ◽  
Vipin Kumar ◽  
Prashant Tripathi ◽  
Abhinav Misra ◽  
...  
Keyword(s):  
Root Canal ◽  
Positive Association ◽  
Signs And Symptoms ◽  
Cultural Analysis ◽  
Clinical Parameters ◽  
Strong Positive Correlation ◽  
Root Canal Therapy ◽  
Positive Correlation ◽  
Microbiological Study ◽  
Group I

ABSTRACT Introduction Success and failure of root canal therapy is largely dependent on the clinician and the patient. Once the tooth is restored into its functional and esthetic place, the root canal therapy is considered to be complete. It is a well-known fact that root canal space acts as a rich reservoir for microorganisms. Past studies show that root canal harbors an array of different microorganisms. Streptococcus mitis and Enterococcus faecalis have been found to be the most prevalent microorganisms isolated from the infected pulp canal space. Hence, we evaluated the association of endodontic signs and symptoms with root canal pathogens. Materials and methods A total of 120 patients were selected for the study and divided broadly into two groups: Group I containing patients with primary infection and group II containing patients in which retreatment was required. Both groups contained 60 patients each. Clinical parameters recorded for the study are pain, tenderness on percussion, swelling, periapical radiolucency on radiographic analysis, caries, sinus formation, and tooth mobility. After assessment, opening, and initial filing, sterile paper points were inserted into the root canal space for collection of microbiological sample, which was further send to laboratory for cultural analysis. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software. Student's t-test and Fisher's exact test were used to evaluate the level of significance. Results While comparing the mean age of the patients in the two groups, no significant association was seen. Statistically significant results were obtained while comparing the association between pain and S. mitis. Positive correlation was seen on comparing the association between tenderness on percussion and E. faecalis. Also, a positive association was seen between periapical radiolucency and S. mitis. Conclusion Strong positive correlation exists between S. mitis and E. faecalis and endodontic signs and symptoms. Clinical significance Sound knowledge regarding the association of microbes of root canal and specific endodontic signs and symptoms could help therapeutic management of root canal infections effectively. How to cite this article Pandey V, Choudhary I, Kumar V, Tripathi P, Misra A, Bagde H. Assessment of Correlation between Clinical Parameters and Pulp Canal Pathogens in Endodontic Pathologies: A Microbiological Study. J Contemp Dent Pract 2016;17(8):654-658.

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