scholarly journals Tests of Independence for a $2 \times 2$ Contingency Table with Random Margins

2017 ◽  
Vol 6 (2) ◽  
pp. 106 ◽  
Author(s):  
Yuan Yu ◽  
Dhiman Bhadra ◽  
Balgobin Nandram
Keyword(s):  
Contingency Table ◽  
Bayes Factor ◽  
Small Sample ◽  
Ratio Test ◽  
Power Functions ◽  
Significance Level ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Cell Counts ◽  
Fisher’S Exact Test

Fisher's exact test is commonly used for testing the hypothesis of independence between the row and column variables in a $r \times c$ contingency table. It is a ``small-sample'' test since it is used when the sample size is not large enough for the Pearsonian chi-square test to be valid. Fisher's exact test conditions on both margins of a $2 \times 2$ table leading to a hypergeometric distribution of the cell counts under independence. Moreover, it is conservative in the sense that its actual significance level falls short of the nominal level. In this paper, we modify Fisher's exact test by lifting the restriction of fixed margins and allow the margins to be random. In doing so, we propose two new tests - a likelihood ratio test in a frequentist framework and a Bayes factor test in a Bayesian framework, both of which are based on a new multinomial distributional framework. We apply the three tests on data from the Worcester Heart Attack study and compare their power functions in assessing gender difference in the therapeutic management of patients with acute myocardial infarction (AMI).

scholarly journals Knowledge, Attitudes and Practices on the Use of Botanical Medicines in a Rural Caribbean Territory

2021 ◽  
Vol 12 ◽  
Author(s):  
Tatijana Vujicic ◽  
Damian Cohall
Keyword(s):  
Medicinal Plants ◽  
Medicinal Plant ◽  
Traditional Knowledge ◽  
Significance Level ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Attitudes And Practices ◽  
Fisher’S Exact Test ◽  
Botanical Medicines ◽  
Knowledge Attitudes And Practices

The worldwide use of medicinal plant products has been steadily increasing over the past few decades, whereas the traditional knowledge and practices of these botanical medicines appears to be diminishing. Considering the need to conserve and document these traditions, the objective of this study was to understand the knowledge, attitudes, and practices of people who are familiar with botanical medicines, as well as any factors that may influence the perceptions and behaviours associated with the use of medicinal plants. A previously validated survey instrument assessing knowledge, attitudes, and practices on the use medicinal plants was randomly administered to residents of three rural Barbadian communities. The data was analyzed using descriptive statistics and cross tabulations (Chi-Square Test, Fisher’s Exact Test), with a confidence level of 95% and significance level of p < 0.05. One hundred and fifty-four participants completed the survey with a response rate of 96%. From participant responses we found that over 75% of the study population used botanical medicines. Key findings included a diverse repertoire of traditional knowledge on the use of medicinal plants, which included a total of 29 medicinal applications cited across 69 different plant species and 39 families. The most popular species among respondents (irrespective of use) were Pimenta racemosa (Mill.) J.W. Moore (FC = 30, RFC = 0.26), Momordica charantia L. (FC = 28, RFC = 0.24), Zingiber officinale Roscoe (FC = 22, RFC = 0.19) and Annona muricata L. (FC = 21, RFC = 0.18). The findings also show the persistence of medico-cultural concepts such as cleansing and cooling, and identified significant associations between the use of botanical medicines and related practices with demographic variables such as education (p = 0.05; Fisher’s Exact Test) and health insurance, χ2 (1, n = 152) = 4.645, p = 0.003. The findings of this study can be used in the identification and archiving of the medicinal plant practices in Barbados and the wider Caribbean, as well as for the larger purposes of biocultural exploration, preservation and further scientific assessment of botanical medicine practices.

Rapid-Cycling Affective Disorder in the Elderly: Clinical Subtype or Specific Course of Manic-Depressive Illness?

1997 ◽  
Vol 10 (3) ◽  
pp. 105-110 ◽  
Author(s):  
Vincent Camus ◽  
Carlos Augusto de Mendonça Lima ◽  
Daniel Antonioli ◽  
Jean Wertheimer
Keyword(s):  
Affective Disorder ◽  
Bipolar Affective Disorder ◽  
The Elderly ◽  
Small Sample ◽  
Rapid Cycling ◽  
Exact Test ◽  
Bipolar Illness ◽  
Fisher's Exact Test ◽  
Fisher’S Exact Test ◽  
Clinical Subtype

Rapid cycling is a relatively unusual presentation of bipolar affective disorder in the elderly. Four cases or rapid-cycling affective disorder (RCAD) in elderly women (aged 78-86 yr) are presented. Two patients began their bipolar illness in adulthood (aged 30 and 49 yr), and rapid cycles appeared secondarily in their elderly years (82 and 76 yr). The other two began their illness immediately with rapid cycles respectively at the age of 62 and 66. Added to the nine cases of RCAD in the elderly previously reported in the literature, a meta-analysis conducted on this small sample suggests that immediate entry in rapid cycles seems more likely to be associated with a late occurrence of bipolar illness (after 60 years of age) ( P = .0035, Fisher's Exact Test, two-tailed), and that very short cycles (< 2 weeks each) are more likely to be associated with female gender ( P = .0047, Fisher's Exact Test, two-tailed). Despite the small size of the sample, these results give some arguments to the hypothesis that RCAD is not a homogeneous syndrome but could be considered as a pattern of evolution, as well as clinical subtype, of the bipolar illness.

scholarly journals Changing Pattern of Childhood Epidemic Cerebrospinal Meningitis in North-Western Nigeria

2018 ◽  
Vol 09 (02) ◽  
pp. 203-207
Author(s):  
Sani Mado ◽  
Ibrahim Aliyu ◽  
Rabiu Murtala
Keyword(s):  
Relevant Information ◽  
Female Ratio ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Cell Counts ◽  
Fisher’S Exact Test ◽  
The Mean ◽  
Pro Forma ◽  
Male To Female ◽  
North Western

ABSTRACT Introduction: Nigeria lies within the meningitis belt which extends from the Gambia, Senegal through Nigeria to Eritrea; however, outbreaks have been shown to extend further south involving countries such as Angola and Namibia. Epidemic outbreaks are often recorded every 8–12 years averaging in a 10 yearly circle however endemic cases still occurs. Materials and Methods: The study was retrospective; all results of cerebrospinal fluid (CSF) samples of children with cases of meningitis from January 2010 to December 2010 were collected from the register of the microbiology laboratory of General Hospital Gusau. Relevant information such as their age, sex, CSF macroscopy/microscopy reports, latex particle agglutination test report, and CSF culture report were retrieved and entered into a pro forma. Results: There were 89 (73%) males and 33 (27%) females with male to female ratio of 2.7:1. The age ranged from 2 months to 14 years; the mean was 6.27 ± 4.00 years. Meningitis was mostly recorded from January to April. W135 was the most common serotype identified. Majority of the samples (54) which were nonreactive for any of the tested antigens had clear CSF (36), while among those that reacted; the W135 group had a high proportion of cases that had turbid CSF (44); (Fisher's exact test = 30.650, P = 0.000). Majority of the samples (99) had no cell count; although those of the W135 group had higher cell counts followed by those in the nonreactive group (Fisher's exact test = 11.226, P = 0.181). Conclusion: Meningitis was highest between January and April, and W135 was the most common serotype.

scholarly journals HUBUNGAN KETEPATAN TRIASE DENGAN RESPONSE TIME PERAWAT DI INSTALASI GAWAT DARURAT RUMAH SAKIT TIPE C

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Jimmy Rumampuk ◽  
Mario E. Katuuk
Keyword(s):  
Response Time ◽  
Sampling Technique ◽  
Handling Time ◽  
Cross Sectional ◽  
Significance Level ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Fisher’S Exact Test ◽  
Type C ◽  
Clinical Conditions

Abstract : The most important thing when the nurse does triage is to do response time. A decrease in the triage scale assessment will extend the handling time that the patients should receive according to their clinical conditions so that it will risk reducing the patient safety rate and the quality of health services. The purpose of this study was to identify the relationship of the accuracy of triage with the response time of nurses in hospital type C Emergency Unit. Samples totaling 36 respondents were taken using total sampling technique. Method used observational analytic research design with a cross sectional approach. The result of study using fisher's exact test at a significance level of 95%, obtained a significant value p = 0.003 or smaller than 0.05 (0.003 <0.05). The conclusion of the results of this study indicate that there is a relationship between the accuracy of triage with the response time of nurses in the emergency room type C hospital.Keywords: Triage, Accuracy, Response Time, IGDAbstrak : Hal terpenting ketika perawat melakukan triase adalah melakukan response time. Penurunan penilaian skala triase akan memperpanjang waktu penanganan yang seharusnya di terima oleh pasien sesuai dengan kondisi klinisnya sehingga akan beresiko menurunkan angka keselamatan pasien dan kualitas dari layanan kesehatan. Tujuan penelitian ini adalah untuk mengidentifikasi hubungan ketepatan triase dengan response time perawat di IGD rumah sakit tipe C. Sampel berjumlah 36 responden yang diambil menggunakan teknik total sampling. Desain Penelitian yang di gunakan adalah observasional yang bersifat analitik dengan pendekatan Cross Sectional. Hasil Penelitian uji fisher’s exact test pada tingkat kemaknaan 95%, diperoleh nilai signifikan p = 0,003 atau lebih kecil dari 0,05 (0,003 <0,05). Kesimpulan hasil penelitian ini menunjukan bahwa terdapat hubungan antara ketepatan triase dengan response time perawat di IGD rumah sakit tipe C.Kata Kunci : Triase, Ketepatan, Response Time, IGD

scholarly journals KEBIASAAN MAKAN MAKANAN TINGGI PURIN DENGAN KADAR ASAM URAT DI PUSKESMAS

2019 ◽  
Vol 7 (2) ◽  
Author(s):  
Veronica Flaurensia Magdalena Kussoy ◽  
Rina Kundre ◽  
Ferdinand Wowiling
Keyword(s):  
Uric Acid ◽  
Eating Habits ◽  
Gouty Arthritis ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Significance Level ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Fisher’S Exact Test

Abstract: Unhealthy community eating patterns by consuming high protein foods that contain high purine levels causes the incidence of hyperuricemia to increase. Consuming high purine foods will increase uric acid levels in the blood, which predisposes to gouty arthritis. The aim was to determine the Corelation between high purine food eating habits with uric acid levels in the working area of Remboken Community Health Center. The research design used descriptive analytic with Cross Sectional Study approach. A sample of 51 respondents was obtained using the Total Sampling technique. The results of statistical test studies using the Fisher’s Exact Test at a significance level of 95%, obtained a significant value ρ = 0.034 <α (0.05). The conclusion is that there is a relationship between eating habits of high purine foods with uric acid levels.Keywords : Purines, Gout, Eating habitsAbstrak : Pola makan masyarakat yang tidak sehat dengan mengkonsumsi makanan berprotein tinggi yang mengandung kadar purin tinggi menyebabkan kejadian hiperurisemia semakin meningkat. Mengkonsumsi makanan tinggi purin akan meningkatkan kadar asam urat dalam darah, yang merupakan predisposisi terjadinya gout arthritis. Tujuan untuk mengetahui hubungan kebiasaan makan makanan tinggi purin dengan kadar asam urat di wilayah kerja puskesmas remboken. Desain penelitian yang digunakan yaitu Deskriptif Analitik dengan pendekatan Cross Sectional Study. Sampel berjumlah 51 responden yang didapat dengan menggunakan tehnik Total Sampling. Hasil penelitian uji statistik menggunakan uji Fisher’s Exact Test pada tingkat kemaknaan 95%, didapatkan nilai signifikan ρ = 0,034 < α (0,05). Kesimpulan ada hubungan antara kebiasaan makan makanan tinggi purin dengan kadar asam urat.Kata kunci : Purin, Asam Urat, Kebiasaan makan

scholarly journals Exact Bayesian p-values for a test of independence in a 2 × 2 contingency table with missing data

2017 ◽  
Vol 27 (11) ◽  
pp. 3411-3419 ◽  
Author(s):  
Yan Lin ◽  
Stuart R Lipsitz ◽  
Debajyoti Sinha ◽  
Garrett Fitzmaurice ◽  
Steven Lipshultz
Keyword(s):  
Missing Data ◽  
Bayesian Analysis ◽  
Contingency Table ◽  
P Value ◽  
Type I ◽  
P Values ◽  
Test Of Independence ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Fisher’S Exact Test

Altham (Altham PME. Exact Bayesian analysis of a 2 × 2 contingency table, and Fisher’s “exact” significance test. J R Stat Soc B 1969; 31: 261–269) showed that a one-sided p-value from Fisher’s exact test of independence in a 2 × 2 contingency table is equal to the posterior probability of negative association in the 2 × 2 contingency table under a Bayesian analysis using an improper prior. We derive an extension of Fisher’s exact test p-value in the presence of missing data, assuming the missing data mechanism is ignorable (i.e., missing at random or completely at random). Further, we propose Bayesian p-values for a test of independence in a 2 × 2 contingency table with missing data using alternative priors; we also present results from a simulation study exploring the Type I error rate and power of the proposed exact test p-values. An example, using data on the association between blood pressure and a cardiac enzyme, is presented to illustrate the methods.

scholarly journals Post-traumatic Complications of Severe Luxations and replanted Teeth

2015 ◽  
Vol 16 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Thiago Farias Rocha Lima ◽  
Juliana Yuri Nagata ◽  
Francisco José de Souza-Filho ◽  
Adriana de Jesus Soares
Keyword(s):  
Root Resorption ◽  
Dental Trauma ◽  
Ratio Test ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
Tooth Avulsion ◽  
Significant Difference ◽  
Fisher’S Exact Test ◽  
Post Traumatic

ABSTRACT Aim The aim of this study was to evaluate the main posttraumatic complications of severe luxation and replanted teeth using clinical and radiographic analyses. Materials and methods Eighty-three patients aged between 7 and 55 years old presenting 180 traumatized teeth that suffered extrusive luxation (n = 67), lateral luxation (n = 69), intrusive luxation (n = 10) and tooth avulsion (n = 34) followed by replantation were evaluated. The follow-up period was 24 months. The complications examined were: pulp canal obliteration, pulp necrosis and root resorption (inflammatory and replacement). Furthermore, the relationship between time elapsed before receiving dental attendance and development of inflammatory resorption was observed. Results Pulp necrosis was the main complication, occurring in 147 teeth (82.7%). All of the teeth that suffered intrusive luxation and tooth avulsion were diagnosed with pulp necrosis, with significant difference in comparison with another traumas (p < 0.001/Fisher's exact test). Inflammatory root resorption was observed in 20.5% of the cases and replacement resorption was more related to tooth replantation (94.1%), showing significant prevalence among tooth luxations (p < 0.001/Fisher's exact test). In addition, it was noted that patients who seek treatment 9 weeks after the trauma episode presented 10 times more chance of developing inflammatory resorption when compared with patients who seek treatment soon after dental trauma (Odds ratio test). Conclusion It may be concluded that pulp necrosis was the main post-traumatic complication observed in traumatized teeth and that delay in seeking treatment may damage the prognosis of severe luxation and replanted teeth. Clinical significance Clinical studies describing the main complications that may affect traumatized teeth present great relevance to make the population aware of the importance of seeking immediate treatment and to alert the professional to the need for follow-up. When traumatic injuries are diagnosed and treated early, post-traumatic complications may be controlled, allowing conservation of the tooth in oral cavity. How to cite this article Lima TFR, Nagata JY, de Souza- Filho FJ, de Jesus Soares A. Post-traumatic Complications of Severe Luxations and replanted Teeth. J Contemp Dent Pract 2015;16(1):13-19.

Public policy and its effects on Mexico’s housing industry

2019 ◽  
Vol 12 (2) ◽  
pp. 246-264
Author(s):  
Luis Raúl Rodríguez-Reyes ◽  
Carlos Omar Trejo-Pech ◽  
Mireya Pasillas-Torres
Keyword(s):  
Public Policy ◽  
Housing Policy ◽  
Great Recession ◽  
Small Sample ◽  
Content Type ◽  
Exact Test ◽  
Fisher's Exact Test ◽  
The Great Recession ◽  
Fisher’S Exact Test ◽  
Housing Industry

Purpose The Mexican housing industry was hindered by a shrinking market and tighter financial conditions related to the Great Recession. Moreover, in 2013, a major change in public policy further modified this industry’s environment. Mexico’s new urban development policy supported inner-city new housing, in contrast to the previous policy that incentivized sprawling. Three out of eight publicly traded housing companies filed for bankruptcy protection in 2013-2014, arguably because of the effects of the Great Recession and the new housing policy. The purpose of this study is to identify firm-level factors that caused some firms to file for bankruptcy protection. Design/methodology/approach Three approaches were used to analyze the housing industry in Mexico from 2006 to 2015. First, a policy analysis focused on the new housing policy and its consequences for housebuilding companies. Second, a financial analysis of the two economic shocks was performed in search for the transmission mechanisms in the companies’ financial metrics. Third, a retrospective analysis using the Fisher’s exact test was used to identify variables statistically associated with companies filing for bankruptcy protection. Findings There are two features significantly associated with bankruptcy protection: increasing market share while being vertically integrated, as a response to the Great Recession, and the relative magnitude of the loss on firms’ inventory value due to the new public policy. Neither Altman’s Z-score values nor firm size or degree of integration are significantly related to bankruptcy. Research limitations/implications The small sample size presented a challenge, as most statistical methodologies require large samples; however, this was overcome by using the Fisher’s exact test. Originality/value The main contribution of this paper is the statistical identification of the possible causes for bankruptcy protection in Mexico amongst homebuilding firms in 2013 and 2014, which have not previously been reported in the literature.

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