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    Factors Affecting The Technical Efficiency Of Boro Rice Producers Of Northern Rigion In Bangladesh
    (University of Rajshahi, Rajshahi, 2021) Kundu, Ranjan Kumar; Karmokar, Provash Kumar
    Because of its significant contribution to the development of various economic-related activities and self-sufficiency in food production, agricultural production needs to increase under the existing challenges so far. Despite increased rice production, it is evident that among all varieties, Boro rice is contributing the largest share of Bangladesh as well. The satisfactory contribution in the production of Boro rice has been unearthed for the Northern regions of the country in this respect. As therefore, investigation of determinants of production risk and efficiency and /or inefficiency may have an important role based on the stochastic production framework. According to the objectives, an attempt has been made to examine the contributory impact of the assigned input variables using frontier modelling. Firm-level primary data of 350 Boro farmers have collected from Rangpur, Dinajpur, Bogura, and Natore districts using an appropriate sampling technique and choice of functional form, distributional assumptions of models. Together with different preliminary statistics related to the research, technical efficiency has computed using Stochastic Frontier Modelling for selected Upazilas and districts. Small unit efficiencies have been computed for the eight Upazilas. The Farmers' Performance Indicators on the integrated management in the efficiency ground has been investigated under the Half-Normal assumption of errors of districts as well as the pooled data.
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    Statistical Modeling for Genome Wide Association Studies
    (University of Rajshahi, 2020) Alam, Md. Jahangir; Mollah, Md. Nurul Haque; Hossain, Md. Ripter; Islam, S. M. Shahinul
    Genomics is the study of the whole genome of any living organism along with its environment and it incorporates different elements from genetics (a branch of biology that generally deals with the heredity). Genomics uses “DNA sequencing methods” to generate sequences of genomes using recombinant DNA, and it utilizes Bioinformatics to assemble the sequences of whole genomes and analyze the structure and function of genomes. It differs from 'classical genetics' in that it considers an organism’s full complement of hereditary material, rather than one gene or one gene product at a time. Moreover, genomics focuses on interactions between loci and allele within the genome and other interactions such as epistasis, pleiotropy and heterosis (Figure 1.1). The availability of complete DNA sequences for entire organisms is made easy by the Genomics. Genomics was made possible by both the pioneering work of Fred Sanger and the more recent next-generation sequencing technology. Fred Sanger's group established techniques of sequencing, genome mapping, data storage, and bioinformatics analyses in the 1970s and 1980s. This work paved the way for the human genome project in the 1990s (Bentley et al., 2008) an enormous feat of global collaboration that culminated in the publication of the complete human genome sequence in 2003. Nowadays, next-generation sequence technologies have led to remarkable improvements in the speed, capacity and affordability of genome sequencing. Moreover, advances in bioinformatics have enabled hundreds of life- science databases and projects that provide support for scientific research. Information stored and organized in these databases can easily be searched, compared and analyzed………….
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    Prediction of Adult Stature of Japanese Boys and Girls
    (University of Rajshahi, 2003) Rahman, J.A.M. Shoquilur; Ali, Md. Ayub
    The longitudinal growth of individual's stature of the present study was characterized from early childhood to adulthood. The samples used here were 509 males and 311 females. A triphasic generalized logistic model (BTT model) and diphasic growth model (JPA-2 model) applied respectively on the above two sets of data through the software AUXAL for characterizing individual growth of stature. The default values of the population mean and covariance matrix in AUXAL for both the models were substituted by estimated population mean and covariance matrix based on Japanese population. The individuals without mid growth spurt for both sexes show that predicted adult stature (PAS) was significantly positive correlated with stature at onset of adolescent and adolescent growth phases, and for only girls VTO and PHV was positively correlated. The individuals with mid growth spurt for both sexes show that PAS was significantly positively correlated with statures at early childhood minimum, mid-childhood maximum, onset of adolescent and adolescent growth phases. Also positive significant correlations were found between VECM and VMC, VTO and PHV but in case of PHV and VMC, negative significant correlation was found. On the basis of JPA-2 model the mean adult stature were 171.27cm for Japanese boys and 158.51 for Japanese girls. On the basis of BTT model this study demonstrates that, on average, 46. 1 %, 39.5%, and 14.4% of the total adult stature were completed during early, middle and adolescent phase of growth, respectively, for the Japanese male population. For the female population, these percentages were 42.6%, 44.6%, and 12.8%, respectively. The distributions of predicted stature that do not have the mid growth spurt, on average, shows that the Japanese girls become taller than boys from age 1 to 5 and 10 to 12, and then again become shorter than boys. The distributions of predicted stature that have the mid growth spurt, on average, shows that the Japanese girls become taller than boys from age 8 and 11 to 12, and then again become shorter than boys. Japanese boys who do not have the mid growth spurt are, on average, 13.26 cm taller than their opposite sex. Moreover, Japanese boys who have the mid growth spurt are, on average, 13. 77 cm taller than their opposite sex. Several equations, after removing the problem of outliers and influential data points, are proposed to predict the adult stature of the Japanese based on growth parameters and statures at different ages.
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    Exploring Toxicogenomic Biomarkers using Statistical Models
    (University of Rajshahi, 2019) Hasan, Mohammad Nazmol; Mollah, Md. Nurul Haque; Begum, Anjuman Ara; Rahman, Moizur
    Toxicogenomics studies combines toxicology with several omics technologies (genornics, transcriptomics, proteomics and metabolomics) to assess the risk of toxins (small molecules, peptides or proteins) and chemical agents (drugs, gasoline, alcohol, pesticides, fuel oil and cosmetics) in organism. Through integration of these omics technologies with bioinformatics, toxicogenomics can be used to suggest the molecular mechanism of toxicity. This can reduce the cost in terms of time, labor, compound synthesis and animal use which are main limitations of traditional toxicology work. There are three main objectives of toxicogenomics studies as well as drug discovery and development. 1) To explore the toxicogenomic biomarkers and toxicity of the doses of chemical compounds (DCCs). 2) Exploration of co-clusters between correlated genes and DCCs. and 3) Detection of significant gene and DCCs interactions. In this thesis, we have addressed all of these objectives in absence and presence outlying observations in the toxicogenomic dataset. There are some online computational tools that can explore the toxicogenomic biomarker genes based on t-test and Mann-Whitney U test. However, these tools cannot identify the significant DCCs that regulate the expression pattern of biomarker genes. To overcome this problem we have described one-way ANOVA together with and tukeys' HSD test (post-hoc test) ( chapter 2) to explore toxicogenomic biomarker genes and the significant toxic DCCs. The biomarker genes identified by the ANOV A approach are functionally annotated and found statistically significant for the respective pathway. The tukeys' HSD test identified toxic DCCs have also been validated by the existing literature. Besides this, according to the characteristics of toxicogenomic data exploration of co-clusters between genes and DCCs is another important objective of toxicogenomic studies. Hierarchical clustering (HC) is very popular and widely applied data analysis tool; it search interesting groups of objects in a dataset based on any combination of distance (euclidean, maximum, manhattan, canberra, minkowski) and HC (ward.D, ward.D2, single, complete, average, mcquitty, median, centroid) methods. However, these distance or clustering methods do not perform equally in grouping objects for all types of dataset. Even the performance of some of these combinations is very poor in some specific field of study. In this thesis ( chapter 3) we have selected more suitable HC methods ward.D or ward.D2 in combination with distance methods euclidean, manhattan or minkowski for clustering genes and DCCs of toxicogenomic data. Furthermore, in chapter 3 we have proposed an algorithm for co-clustering between genes and DCCs based HC approach. Though the selected HC clustering approaches together with the proposed co-clustering algorithm can co-cluster the genes and DCCs, these approaches are very sensitive to outlying observations. Therefore, we robustify the selected HC approaches in chapter 4. We observed that the proposed robust HC (RHC) approaches outperform over the classical HC approaches. The gene-DCCs co-clustering results based on RHC using the co-clustering algorithm (proposed in chapter 3) have been validated by the existing literature. Nonetheless, the classical clustering approaches (e.g. k-means, fuzzy, HC, etc.) including our proposed RHC use one-way (gene or DCCs) information for clustering/co­clustering. Thus, these clustering approaches is not flexible and effective for co­clustering genes and DCCs. On the other hand, probabilistic hidden variable model (PHVM) uses two-way (gene and DCCs) information simultaneously for co-clustering between genes and DCCs. Therefore, this approach is more effective and suitable for co­clustering. However, the PHVM approach is not robust against outliers. To overcome this limitation of PHVM in this research (chapter 5) we have proposed logistic PHVM called as LPHVM for robust co-clustering between genes and DCCs discover toxicogenomic biomarkers and their regulatory DCCs. We have observed that the proposed LPHVM approach perform better compare to PHVM and classical co-clustering approaches based on the results of the simulated and real data analysis. In order to answering toxicogenomic questions researchers are being suggested different suitable offline and online computational tools, since a single computational algorithm cannot always produce the answers of the toxicogenomic questions. This is because; large scale datasets have been generated by the complex toxicogenomic experiments. For example, the co-clustering approaches based on HC and hidden variable models sometimes cannot separate the significant up-regulatory (UpR) (the gene is up-regulated by the influence of the DCC) and down-regulatory (DnR) (the gene is down-regulated by the influence of the DCC) gene-DCC interactions from the equal-regulatory (EqR) (thereis no DCC effect on that gene) interactions within a co-cluster. On the other hand, separation of UpR and DnR gene-DCC interactions from the EqR interactions is the cornerstone in toxicogenomics studies as well as in drug discovery and development. Therefore, in chapter 6 we have proposed MRC and LMRC for the detection of significant gene-DCC interactions, so far of our knowledge which have not been considered yet in toxicogenomic studies as well as in drug discovery and development. However, LMRC produces robust results compare to MRC in presence of outlying observations in the data otherwise they perform equally.
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    Factors Associated with Target Fertility in Bangladesh
    (University of Rajshahi, 2012) Karim, Md. Rezaul; Islam, Md. Nurul
    In this study, an attempt has been made to assess the factors associated with target fertility in Bangladesh using nationally representative data from Bangladesh Demographic and Health Survey (BOHS), 2007. Simple linear regression as well as multivariate techniques named logistic regression analysis have been used to find out the direct, indirect and combined (interaction) effects of the selected socio-demographic factors on fertility. To quantify the proximate variables, we apply Bonga arts' model as well as proposed Bogart’s' model. The results of the study show that several socio-economic (socio-economic, demographic) variables effect on fertility behavior. These are age at marriage, place of residence, religion, region, education of women and men (partner's/husband's), working status of women, occupation of women and men (husband's), women's participation at NGO's, age at first birth of women, length of breastfeeding practice, contraceptive use, number of dead children (boys and girls) etc. Fertility is still high in Bangladesh, though it has been declining over time. A major cause of declining fertility has been the steady increase in contraceptive use over the last 32 years; another major cause of declining fertility has been the steady increase the age at marriage. Current contraceptive prevalence rate (CPR) is 56% in 2007 BOHS (Mitra et, al., May 2009). The effect of marriage pattern and marital fertility, on the overall fertility of Bangladesh examined by Coal’s indices show higher influences of marriage pattern than that of marital fertility. The effect of change of marriage pattern in reducing fertility level perhaps has increased over time. Again, the age pattern of marriage and the contraceptive use have changed in a positive direction, the negative impact of which has fallen on fertility. Examination of the changes of the indicated indices at various time segments that the changed could be a recent phenomenon. To identify the change of fertility in terms of proximate variables, Bonga art’s model has been used. Among the variables in the analysis of proximate determinants of fertility happened to be in response of the effect of increase in proportion married and contraceptive use. These determinant shows that 5.69% decline due to change in the proportion of women married, 12.36% decline due to contraceptive use, 0.596% decline due to increase the index of fetal wastages and approximately 20.38% increase due to decrease of the duration of lactational in fecundability. Application of Bonga arts · model indicates that there is a downward trend in all the proximate indices. Between 1997 and 2007 the amount of decrement of total fertility rate is about 17.51 % and it is about 10.139% between 2004 and 2007. This is primarily caused by an increase in the use and effectiveness of contraceptives. The divorce and widowhood have also a major contribution on reduction of the fertility in Bangladesh. Observed TFR found to be 2.7 in 2007 and Bonga arts' model estimate the TFR is 3.21 which is far away from observed TFR but our proposed model estimates the TFR is 2. 76 which is closer to the observed TFR. Again, for consideration only abortion index in Bonga arts · model the estimated TF is 12.83 which is far away from assumed TF and our proposed model gives the value of TF is 14.99 which is very close to observed TF (15.3). So, comparing the estimated values we conclude that proposed model is better than Bonga arts· model. The study of differential fertility indicates the inverse relationship between age at marriage and fertility; education of women, men (husbands) and fertility; occupation of women, men (husbands) and fertility. We observed that fertility is higher in rural areas. There are several reasons, these include may be the rural women are less educated than urban women; rural women have poor media connection etc. Regional difference reveals that fertility is higher in Chittagong, Sylhet and Barisal than from Khulna, Rajshahi and Dhaka division. Dhaka and Rajshahi division have intermediate levels of fertility. Religion has effect on fertility behavior through Muslims and Non-Muslims. The analysis shows that fertility among Muslims is higher as compared with non-Muslims in each age group. Several variables, such as, work status of women, women's participation at NGO's suggests that labor force participation may be consequence of lower fertility than non-working counterpart. Women who are involved, with any service are not dependent on men (husbands), both socially and mentally have their own rights and absence of dependence, men cannot forcibly use women to increase their fertility. This has resulted in lower fertility. Results of logistic regression analysis indicates that place of residence, religion, age at marriage of women, age of first birth of women, women's education, contraceptive use, women's currently working status, pregnancy status, number of living children, access of mass media and involvement in NGO's are ttie most important significant variables that influence fertility in Bangladesh. According to the regression, the TFR equals, on average 7.742 births per women in the absences of contraception (CPR=0), and fertility declines at a rate of approximately 1.0 birth per women for each 9% increment in the contraceptive prevalence rate. The regression equation of TFR on CPR suggests that a TFR of 2.4 births per women can be achieved if the level of CPR will be raised to 61 % and if the level of CPR will be raised to 65% it is possible to achieve a target TFR level of 2.1 births per women. The prevalence rates are computed at the effectiveness levels of 0.85 and 0.90 such effectiveness of contraception has already reached 0.85 in the year 2007. The results indicate that if target fertility 2.6 is to be achieved then the CPR will be raised to 58% and 57% with 0.85 and 0.90 effectiveness respectively. Similarly, if target fertility 2.1 can be achieved the CPR is to be approximately 68% and 66% with 0.85 and 0.90 effectiveness respectively. The result also found that to reach the desired level of target fertility it must increase the use of contraception, duration of breastfeeding, singulate mean age at marriage and amenorrhea period. To achieve replacement level of fertility at 2.1 births per women we should increase the CPR, SMAM, duration of breastfeeding and amenorrhea period by 68%, 20.80 years, 15.5 months and 22.56 months respectively.
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    Application of Complex Lifetime Models for Analysis of Product Reliability Data
    (University of Rajshahi, 2016) Ruhi, Sabba; RezaulKarim, Md.
    Proper data collection and analysis are very important for effective investigation of product reliability. Data is critical for building and selecting suitable statistical models and model provides new insights for improvements to maintenance and management operations in manufacturing industries. Regarding variations in product quality and reliability, component nonconformance and assembly error are two important problems which occur frequently in manufacturing industries. In such situations, the complex lifetime models are required for analyzing product reliability data. This thesis proposes a general model for modeling the effects of quality variation. This model includes the mixture model and competing risk model as the special cases. The thesis applies these models for analysis of three sets of product reliability data - Aircraft windshield failure data, Battery failure data and Hydraulic pump failure data. A set of competitive 2-fold and 3-fold mixture models are considered for modeling the data sets. The maximum likelihood estimation method via the Expectation Maximization (EM) algorithm is applied mainly for estimating the parameters of the models and reliability related quantities. For the Aircraft windshield failure data, results indicate that the method of estimation with the EM algorithm procedure is better than the Weibull Probability Paper (WPP) plot procedure. For Battery failure data, based on the measures of lifetime quantities, it can be concluded that data without maintenance information provides approximately similar results with the data having maintenance information. According to the graphical representation and estimated values of different model selection criterions, we found that the 3-fold Weibull-Normal-Exponential mixture model can be selected as the best model for the Hydraulic pump failure data. The selected distribution for pumps with assembly errors failure mode is Normal and the distribution for pumps without assembly error failure mode is Weibull. According to the optimization of the proposed objective function, the 3-fold Weibull mixture model gives a bit larger optimal maintenance period, however the Weibull-Normal-Exponential model shows a reduction in the maintenance cost for the pump. Simulation studies are conducted for investigation the performances of the proposed models and methods. The simulation results indicate that the proposed models and methods of estimation are applicable for analyzing 2-fold and 3-fold mixture models for censored product reliability data with incomplete information. The results presented in this thesis would be useful for managerial implications in assessing and predicting the reliability and maintenance cost of the products. Keywords: Product reliability, Data analysis, EM algorithm, Mixture model, Competing risk model, Simulation.
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    Probability Pattern and Effect of Extinction of Disease on Expectation of Life in Bangladesh
    (University of Rajshahi, 2014) Sarkar, Aziza Sultana Rosy; Islam, Md. Nurul
    Mortality is one of the three components of population change. There are several causes of mortality which are different from country to country, age to age, sex to sex and present to past. A large number of people die every year by various causes of mortality in the world. Some causes of mortality mostly which are communicable are almost eradicated by following preemptive measures whereas some other causes of mortality i.e. non-communicable diseases exhibit challenging burden. In this study an investigation has been made to get a clear conception regarding mortality, morbidity and relevant issues. So, the purpose of this study is to examine the trends and probability patterns of deaths by age due to a cause of deaths in presence of all causes and also to identify the main causes of deaths those influence the mortality rate. An attempt has also been made the eliminating effect of specific diseases on expectation of life. Again, one of the components of population analysis is the study of differential of mortality classified by socioeconomic status and demographic characteristics. Thus this study attempts to identify important factors influencing non-communicable diseases related mortality. Finally, we find out the expected non-communicable disease related deaths in Bangladesh and setting the targets to control non-communicable diseases as a future plan in health sectors. Mortality trends and patterns in Bangladesh are primarily presented in the form of frequency distributions, prevalence rates, and mortality rates. This study uses Abridged Life table, Multiple Decrement Life table, Single Decrement Life table, Exponential Growth model, Polynomial Regression model, Logistic Regression model and ARIMA model for analyzing data to quantify the objectives of the study. This study uses the vital registration and maternal and child health data gathered from Matlab, Bangladesh in 2000, 2004 and 2008 collected by the Health and Demographic Surveillance System of ICDDR,B (International Centre for Diarrhea Disease Research, Bangladesh). Also, this study based on primary data which have been collected from 30th ward in Rajshahi City Corporation, Bangladesh. The result of this study shows that a huge number of people died because of non-communicable diseases. This number rapidly increases year by year at a large scale. Among non-communicable diseases, circulatory system related diseases (stroke, ischemic heart disease and hypertensive disease) is significant in Bangladesh. The second major cause of death is neoplasm for the national population. The analysis also warns that the burden of non-communicable diseases will significantly increase as the proportion of people aged over 40 rise. The government of Bangladesh should take necessary action to handle all the non-communicable diseases for achieving desired life expectancies in order to become a healthy nation. Some efforts have been made by governmental and non-governmental organization to set a sustainable system including physician and non-physician workers, health workers. In addition adequate supply and access to the essential medications is keenly ensured especially for the poor. Counseling services about the guidelines, treatments of non-communicable diseases for the male and female need to be arranged. Health services according to age and sex should be fixed up as an immediate goal to control the mounting trends of non-communicable diseases.
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    Impact of Early Childbearing on the Health of the Mother and Child: A Statistical Study
    (University of Rajshahi, 2013) Islam, Md. Ashraful; Islam, Md. Nurul; Hossain, Md. Golam
    Recent research has document the focus of rapidly growing interest on adolescents’ and their child health in the developing and under developed countries because of its important implications not only for the health of mother but also their children. Early childbearing is an important indicator for women’s and their child health. Body mass index is an indicator of nutritional status in a population. This indicator provides the circumstances that can assist intervention to help eradicate many preventable diseases. Health impact of teenage childbearing is not only due to socio-demographic factors but also due to biological factors. Women early age at first marriage were associated with early childbearing and early childbearing is considered as a risk factor for poor prenatal outcomes. There is a need to study demographic trends particularly trends in marriage under the framework of “basic need strategy”. The objectives of “basic need strategy” among others are to eradicate poverty, unemployment, hunger and literacy is considered as a major precondition for achieving population goals and the participation of women in development. The main objective of this study is to evaluate and analyze the impact of early childbearing on the mother and their child health of rural and urban community in Bangladesh. The specific objectives were: first one, to find the effect of socio-demographic factors on early childbearing mother’s health; second one, to investigate the changes in age at first marriage of Bangladeshi women over time and third one, to estimate the parameters involving in the age patterns of marriage and evaluate the patterns (using single year age distributions) of distributions of first marriage frequencies and risks of the first marriages of ever married women in Bangladesh. Finally, the purposes of the study were to demonstrate the applicability of the generalized Poisson regression (GPR) model as an alternative of other statistical methods and to find some predictors of child malnutrition in Bangladesh. Considering the reproductive women (age 15-49 years), data was extracted from Bangladesh Demographic and Health Survey in this study. For measuring mothers’ health a sample of 1908 ever-married women of age 10-24 were used from the total sample of 10,966. For investigate the age at first marriage and its trends over time, data for 47,109 married Bangladeshi women from 1944-1985 were analyzed. To estimate the parameters of Coale’s nuptiality model and evaluate the patterns of distributions of first marriage frequencies also risks of the first marriages of ever married women in Bangladesh, eventually all of 10,996 ever married women from age 15 to 49 years were taken. To examine the health problem and risks faced by early childbearing mothers’ children in Bangladesh a total sample of 3,207 were extracted. Logistic regression was used to examine the relative importance of socio-demographic factors on early childbearing mothers’ health. ANOVA and linear regression analysis were used to investigate the changes in age at first marriage of Bangladeshi women over four decades. The first marriage frequency and risk of first marriage of women was estimated by Coale and McNeil (1972) model. This model considered five year age group of population. In the present study single year age distribution of ever married female in Bangladesh has been considered. Finally for measuring child health Chi-square test and GPR model were used. More than 33 percent early childbearing mothers have been suffering from chronic energy deficiency, among them 35.4 percent came from rural and 26.9 percent from urban. The BMI varied from 11.95 kg/m2 to 37.79 kg/m2, with a mean of 19.86 ± 2.70 kg/m2 (95% CI: 19.74-19.98). About 15.7 percent women fall below the cutoff of 145 centimeters in height. A decreasing trend was found in the number of CED women with increasing educational level. Student t-test revealed that caesarean mother had a higher BMI than non-caesarean mother (p < 0.001. The coefficients and odds ratio of logistic regression analysis demonstrated that early childbearing mothers who were from rural areas, illiterate, hard laborer, unemployed partner, poorest, non-caesarian, delivered at home, earlier age at first marriage, early age at first birth, having two or more children, were at higher risk for getting chronic energy deficiency (underweight). Based on Wald statistics (16.258) we conclude that age at first marriage was the most influential variable on early childbearing and undernourished mother in Bangladesh. The mean and median age at first marriage of ever married Bangladeshi women was 14.73 ±2.96 years and 14.00 years, respectively; rural women got marriage significantly (p<0.01) earlier than urban women. More than 85 percent (rural 87.6 percent and urban 78.2 percent) Bangladeshi women got marriage before they reached 18 years old, among them 17.0 percent (rural 18.5 percent and urban 13.1 percent) got marriage very early age (before 13 years old). The present study demonstrated that the age at first marriage of ever married Bangladeshi women was showing increasing tendency with changing time. Using ANOVA, age at first marriage for rural and urban showed significant (p<0.01) differences among the birth year cohorts from 1944 to 1985 of the present sample. However, the slope of linear regression line indicated that age at first marriage for both rural and urban women exhibited increasing tendency during the investigated period. Also, the present study demonstrated that the child marriage among Bangladeshi women showed slightly decreasing tendency during birth year cohorts from 1944 to 1985. Coale’s model was used to find the age pattern of marriage among Bangladeshi women. The model gave us interesting results. Most of female got married before the age of 20 years with almost 100 percent getting married by the time they reach age 30. In Bangladesh the legal age of marriage is 18 years old for the women; however a large proportion (about 95 percent) of marriages below this age still take place. The GPR model has been found to be reasonable to study the outcome variable because of its under-dispersion (variance < mean) property. Our study also identify several significant predictors of the outcome variable namely; region, place of residence, father’s and mother’s education, mothers occupation, wealth index, delivery system, place of delivery, source of drinking water of the household, toilet facility, and total number of children ever born to a woman. These above results suggest that for improving health status of Bangladeshi early childbearing mothers, are need to improve the literacy. The result also suggest that age at first marriage of Bangladeshi women has been increasing for last four decades, and increasing rate of urban women is faster than rural women. Moreover, the study confirms that marriage still remains a universal phenomenon among females in Bangladesh. Early marriage prevails that marriage not only start early but progresses fast and are concentrated within a short span of time at least in the female population. Consistencies of our findings we suggest that the GPR model is an ideal alternative of other statistical models for analyzing child malnutrition in a family.
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    Determinants of Hypertension in Bangladesh: A Case Study of Rajshahi District
    (University of Rajshahi, 2013) Ali, Md. Ayub; Mondal, Md. Nazrul Islam; Ali, Md. Ayub
    Hypertension is a silent killer of human life and the numbers of hypertensive patients are increasing globally and nationally. Therefore, the purpose of the study was to investigate age-specific hypertension patterns, alarming age for hypertension, and many determinants of hypertension in Bangladesh, e.g., feminine and nuptial determinants, socio-demographic determinants, health complication determinants, and body composition determinants. The data were collected from Rajshahi district using stratified multistage sampling with technique based on the scheduled questionnaire for this study. To identify the most important determinants, sophisticated statistical tools have been used such as percentage distribution, point bi-serial correlation, phi correlation, Pearson product-moment correlation, path analysis, boot strapping technique, binary backward logistic regression method including Likelihood ratio test, Hosmer-lemeshow test, Nagelkerke R2, Sensitivity and specificity, receiver operating characteristics (ROC) curve etc. It was found that the number of systolic hypertensive patients (60.40%) were greater than diastolic hypertensive patients (47.90%) in old age group (≥61 years) where diastolic hypertensive patients (7.40%) were greater than systolic hypertensive patients (3.80%) in young age group (≤39 years) and in middle age group (40-60 years) both are same. Hence, young age (≤39 years) was risk period for occurring diastolic hypertension than systolic and old age (≥61years) was risk period for occurring systolic hypertension than diastolic when middle age (40-60 years) was also risk period for occurring both type of hypertension. The differences between two same percentiles of systolic and diastolic blood pressure were varying from 51 mmHg to 93 mmHg for hypertensive respondents where it is same for normotensive. Hence, the abnormality (>40 mmHg) of the differences is an indicator of hypertension or prehypertension. From the view of proper critical analysis of impact of some key factors on hypertension, the study was divided into four aspects such as socio-demographic, feminine and nuptial, health complication and body composition aspects. About 28.10% hypertensive patients were due to socio-demographic aspect. Applying binary logistic regression model in the study of causal relationship, age was found as the most significant variable. i. e. age had positive significant impact on hypertension. Secondly, education had second most significant negative impact on hypertension and its odds ratio focus that for every increase of one year in education, the risk of hypertension increased 0.958 time. It was also found that sedentary life style, working hour (>8 hrs) per day, social stress, occupational stress and mental stress, hereditary hypertension, smoking, taking alcohol and taking excess salt had positive significant impact on raising hypertension where taking regular exercise had negative significant impact on hypertension. Hence, sedentary life style, working hour (>8) per day, social stress, occupational stress, mental stress, hereditary hypertension, smoking, taking alcohol, taking excess salt may be considered as risk factors for raising high blood pressure or hypertension. Though the age was found to be as the highest risk factor, but age increasing is out of human control. In the health complication aspect, the adult hypertensive patients were 30.60%. In the analysis of causal relationship (applying binary backward logistic regression method) between hypertension and other health complication, kidney disease was found as a significant variable. i. e. kidney disease had positive significant impact on hypertension and its odds ratio 5.428 indicates that the respondents with kidney disease had 5.428 times risk to occur hypertension than the respondent without kidney disease. Also, tumor, diabetes, sleep apnea, hypothyroidism, hyperthyroidism, tachycardia and overweight had the positive significant impact for occurring hypertension. After discussing the binary logistic regression it was further found that kidney disease, tumor, diabetes, sleep apnea, hypothyroidism, hyperthyroidism, tachycardia and overweight might be considered as risk factors for raising high blood pressure or hypertension. In selected feminine and nuptial aspect, the active married female hypertensive patients were 28.90%. In the study of causal relationship (applying backward binary logistic regression model) between hypertension and other feminine and nuptial characteristics, first menstruation age was found to be as significant variable. i. e. first menstruation age had negative significant impact on hypertension. Duration of couple life had significant positive significant impact on hypertension. Use of contraceptive method, menopause, pregnancy and miscarriage had positive significant impact for occurring hypertension compared with those who do not possesses the characteristics. Hence, first menstruation age, duration of couple life, use of contraceptive method, menopause, pregnancy and miscarriage might be considered as risk factors or determinants for raising high blood pressure or hypertension. Using path analysis, the total effect of body mass index, abdominal circumference and ratio of waist to hip on systolic blood pressure were 0.207, 0.185 and 0.118 respectively in which their direct effect were respectively 0.146, 0.082 and 0.047. The total effect of body mass index, abdominal circumference and ratio of waist to hip on diastolic blood pressure were 0.289, 0.231 and 0.138 respectively in which their direct effect were respectively 0.231, 0.079 and 0.043.
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    Demography of Aging : Lessons from Bangladesh
    (University of Rajshahi, 2001) Hossain, Md. Ripter
    The aging of population is thought to be the outcome of interplay between fertility and mortality. So is the case with Bangladesh. In the face of socio-economic transformations that are taking place in Bangladesh, it is assumed that the demographic transition what has been underway in the country in recent years affects the upper age spectrum of the population and has resulted in increase of the older persons of age 60 and over. However, the demographic consequences of changing population age structure and the growing number of older persons are yet to fully understood. The present study is an attempt to explore the causes and consequences of population aging in Bangladesh. The aim of the study is to explore the current situation and future trend of population aging under the changing condition of demographic variables, specifically, fertility and mortality. The objectives of the study are: ■ to look at the change in the level and pattern of fertility and mortality and their effect on the age structure of the population, ■ to examine the impact of undergoing demographic transition on aging of population, ■ to investigate the current age-sex structure of the aged population and to asses future trend under various demographic alternatives and ■ to understand the consequences of population aging in the country. The study has been based on secondary sources of data. The secondary data have been taken from different published and unpublished sources. These are Vital Registration, Population Census, Demographic Survey of East Pakistan, Population Growth Estimation Experiment, National Impact Survey, Bangladesh Retrospective Survey on Fertility and Mortality, Bangladesh Fertility Survey, Bangladesh Contraceptive Prevalence Survey, Bangladesh Demographic and Health Survey, Demographic Surveillance System and some others. Besides these sources, data are also taken from United Nations publications. The study has been carried out on the basis of such demographic indicators as crude birth rate, crude death rate, total fertility rate, median age, age and sex composition, marital status, life expectancy, and so on. The study has analyzed the demographic transition caused by reduction in fertility and mortality and also identify the factors affecting the aged population. To estimate and project the aged population, the models viz. Exponential growth model, Modified exponential growth model, Geometric model, Makeham's model and Logistic model have been used. The study has estimated and projected mid-year female population of Bangladesh by age group during 1991-2021 and through applying Frejka's component method in Leslie matrix form. Finally, Cohort component method has been used to estimate and project the mid-year total population of Bangladesh by age group. The expected trend in aging of population of Bangladesh reveals a clear increasing level in aging population both in case of males and females. As regards age structure it is found that the elderly population( 60+) has increased by 1 percent during 1911 to 1991. The projected figure of elderly population in Bangladesh shows that the size of the elderly population is expected to increase from nearly 6.02 million in 1996 to 7.78 million in 2006. It is also evident that there is a consistent increase in the proportion of aged 60+ compared to the population in those of young and adult age groups. Thus older population of Bangladesh is going to increase remarkably between the next two decades from 2010 to 2030. The exponential growth rate of elderly population in Bangladesh is lower than the other Asian countries. With regard to demographic change the crude birth rate has reduced to as low as 25.6 percent in 1996 from 53.8 percent in 1901. The total fertility rate has also declined with narrow amplitude. It has reduced from 6.78 in 1961 to 3.41 in 1996. Comparison of crude birth rate with the proportion of aged population reveals an inverse relationship between the two. So is the case between the aged population and total fertility. With the decline of total fertility, the aged population would gradually increase. Crude death rate has also an uninterrupted declining trend over the period of the study. Reduction of mortality has however been the important factor in triggering off the rapid growth of population in Bangladesh. Again a considerable decline in infant mortality is noticed in the second half of the twentieth century. Infant mortality reduced to 67 deaths per 1000 live births in 1996 against 140 in 1960. As regards crude death rate and expectation of life at birth, there is a close relationship between the two variables. The average length of life has increased more than double in this century from 24 years in 1901 to 59 years in 1996. The relation of crude death rate with aged population reveals that about 77 percent variation in the proportion of aged population is explained by crude death rate. About 99 percent variation in such proportion is explained by expectation of life at birth. As regards to nuptiality, significant changes in marital composition and in the mean age at marriage are noticed. The mean age at marriage of females has increased to 20.1 years in 1996 as against 12.6 years in 1931 and for males to 27.8 years from 19.0 years during the same period. Both the factors are closely related to fertility thereby affect the aging of population. Estimate and projection of the aged population reveal that in next 20 years their number will exceed nearly one crore and in the mid of the next century the elderly( older persons) is expected to increase nearly 205 times than today. The aged population of Bangladesh will increase gradually up to 2021 and thereafter it will increase remarkably between 2021 to 2051 about 4.6 times by the end of 2051 from the figure of 1981. Thus, we have clear evidence that the aging of population that is taking place in the country can be accounted for the transition of both fertility and mortality i.e. the demographic transition vis-a-vis changes in the age structure. In view of growing number of elderly m Bangladesh, the aged population gradually emerges as a vulnerable group in our society. The well-being of the older person requires formulation of appropriate polices and programmes through a clear understanding of the problems, needs, and demands of this vulnerable group, their status and functions in the family and society, their living arrangement, support systems, economic activity, potentiality and so on. Population aging in Bangladesh is becoming a serious concern for the development agendas. The issue should be dealt with much care. The rapid rate of aging of population and the growing cohorts of older persons have particular implications for the development of the country including increasing economic dependency and rising incidence of care giving to older persons by the traditional social unit, the family. Maintenance of joint family system could be a policy option.