In survey research, accurate collection and recording of information is very critical. The researcher must deal with many potential problems. First the response rate may be poor due to various reasons such as poorly prepared survey instrument, poor execution of survey, survey questions being very personal in nature, and untrained field workers. Some of these issues lead to measurement errors which are the most common form of non-sampling errors. More formally, these errors are defined as the difference between the true value of a variable and its recorded value. It is for this reason these errors are also known as observational errors. Measurement errors have been studied by various authors with Cochran (1963) drawing early attention to these errors. While mean estimation for nonsensitive variables has been studied extensively in the presence of measurement errors, no attempt has been made to study mean estimation for sensitive variables in the presence of measurement errors. By sensitive variable, we mean a variable for which there is a natural tendency on the part of survey respondent to either refuse to answer or to give a socially desirable answer as opposed to correct answer. Randomized Response Technique (RRT) introduced originally by Warner (1965), and later refined by many researchers, is a great tool to deal with the problem of social desirability bias in surveys involving sensitive questions. The main focus of this thesis is on introducing a generalized mean estimator for non-sensitive as well as sensitive quantitative variables in the presence of measurement errors, and on studying the impact of measurement errors on mean estimation. In Chapter 1, we have provided a brief discussion about measurement errors, sensitive variables, and various versions of the Randomized Response Techniques (RRT). Furthermore, measurement errors under simple random sampling and stratified random sampling have been illustrated. Greater details on these two important topics, measurement errors and randomized response methodology, are provided as part of literature review in Chapter 2. In Chapter 3, we have reviewed some existing mean estimators for non-sensitive and sensitive study variables in the presence of measurement errors under both sampling designs. The major contributions of this thesis start from Chapter 4. In this chapter, a generalized mean estimator for a non-sensitive study variable under simple random sampling design has been proposed to examine the impact of measurement errors on mean estimation. Some special cases for generalized mean estimator have also been discussed. In Chapter 5, we continue the study undertaken in Chapter 4 but in the context of the stratified random sampling design. Chapters 6 and 7 are very important chapters where we have examined the impact of measurement errors on mean estimation of a sensitive study variable under the simple random sampling design and the stratified random sampling design respectively. We have used extensive simulations and numerical examples to validate our theoretical findings. Finally some concluding remarks with some possible future directions are mentioned in Chapter 8.
چلے چلو کہ منزل ابھی نہیں آئی نحمدہ ونصلی علی رسولہ الکریم امّا بعد فاعوذ بااللہ من الشیطن الرجیم بسم اللہ الرحمن الرحیم معزز اسا تذہ کرام اور میرے ہم مکتب شاہینو! آج مجھے جس موضوع پر لب کشائی کا موقع مل رہا ہے وہ ہے:’’چلے چلو کہ منزل ابھی نہیں آئی ‘‘ صدرِذی وقار! منزل کے حصول کے لیے جدوجہد ہر ذی روح کی خواہش رہی ہے، ہر کس و ناکس اس کے لئے کدوکاوش کرتا ہے، اس کی زندگی کا ہر لمحہ حصولِ منزل کے لئے وقف ہوتا ہے، ہمہ قسم لوگ شبانہ روز اس مقصد کے حصول کی خاطر کوشاں رہتے ہیں ، حصول منزل میں ہر آنے والی رکاوٹوں کو ختم کرنے کے درپے ہوتے ہیں، اور پھر یونہی ان کے لمحاتِ زیست گزرتے رہتے ہیں۔ جنابِ صدر! حشرات الارض سے لے کر انسان تک ہر ایک اپنی منزل کی طرف گامزن ہے، ہر ایک کی اپنی ایک منزل ہے، مورومگس کی منزل اور ہے، گل لالہ کی منزل اور ہے، جوئے نغمہ خواں کی منزل اور ہے، حر یرو پر نیاں کی منزل اور ہے، زمین پر رینگنے والی مخلوق کی منزل اور ہے، گل لالہ کے گردبھنبھنانے والی شہد کی مکھی کی منزل اور ہے، غلاظت پر چکر لگانے والی مکھی کی منزل اور ہے۔ صدرِ محترم! گلستان میں عندلیب خوش الحان کی منزل اور ہے، برگد کے درخت پر موجود بوم کی منزل اور ہے، آبادی میں شجر سایہ دار کی منزل اور ہے، ویرانے میں خشک تنے والے درخت کی منزل اور ہے، فضاء میں محو پرواز عقاب وشاہین کی منزل اور ہے ،مُردار کے گرد چکر لگانے والی گدھ کی منزل اور ہے۔ پرواز ہے دونوں کی اسی ایک فضا میں کرگس کا جہاں اور ہے شاہیں کا جہاں اور جنابِ صدر!
Objectives: 1. To determine the impact of duration of exposure to industrial chemical fumes on Peak Expiratory Flow Rate (PEFR) and blood pressure of the industrial workers. 2. To find out the association between changes in blood pressure and PEFR due to exposure to industrial chemical fumes in these subjects. Methods: This cross-sectional study was performed at Aziz Fatimah Medical and Dental College, Faisalabad. The study participants were 151 males working in the chemical industries. The study was approved by institutional ethical committee and informed consent was taken from the participants. Free camp was arranged for three days in September 2020 in the industrial area of Faisalabad. Thorough history of exposure to chemicals was taken using structured proforma. PEFR values were recorded using Wrights handheld peak flow meter. Blood pressure was taken by auscultatory method using mercury sphygmomanometer. Data was analyzed using SPSS version 22. Results: Systolic and diastolic blood pressures were significantly raised with increase in duration of exposure. PEFR levels were significantly declined with increase in duration of exposure to chemicals. Significant negative association was noted between diastolic blood pressure and PEFR (p value = 0.003). Negative correlation was observed between PEFR and systolic Blood pressure, however it was not statistically significant (p value = 0.92). Conclusions: PEFR decreased while Systolic and diastolic blood pressures increased significantly with increase in the duration of exposure to chemicals. There was a significant negative correlation between PEFR and diastolic blood pressure while there was no association between PEFR and systolic blood pressure.
Brinjal shoot and fruit borer (Leucinodes orbonalis Guenee) is a serious pest of brinjal and is responsible for colossal yield losses. The pest is mainly controlled by chemical insecticides which poses serious threats to human and environment thus demands the use of alternatives. The present studies were conducted with the objective to manage the pest with various methods other than use of chemical pesticides. Use of resistant cultivars is an economical and environmentally safer methods in pest management. In this regard thirteen brinjal cultivars were tested for their resistance against the pest on the basis of fruit infestation. The cultivars Nirala and Anmol were found relatively resistant, Karishma, Kanha (091) and Ep-273 were intermediate resistant and Naeelam and Black long were categorized as susceptible. In another experiment, relationship between various physico-morphic characteristics of brinjal cultivars and pest infestation was studied. The results showed variable infestation levels of L. orbonalis on different cultivars. Cultivar Naeelam showed maximum fruit infestation (58.60 and 48.09%) followed by Black long (47.93 and 33.31%), while minimum was observed in Nirala with (24.75 and 21.57%) fruit infestation during 2007-08 and 2008-09, respectively. Similarly, shoot infestation was found maximum in Naeelam (43.15 and 33.75%) followed by Kanha-091 (37.72 and 28.73%) and Nirala was found as least attacked by the pest showing 19.27 and 15.81% shoot infestation during 2007-08 and 2008-09, respectively. The correlation of different morphological plant characters with fruit infestation indicated very strong but negative correlation between fruit infestation and leaf trichomes, stem thickness and stem hair density. A negatively significant correlation was found between fruit infestation and plant height (r = -0.716), crown hair density (r = -0.672) while the correlations with leaf hair density (r = -0.623), and leaf area (r = -0.613), was also significant but negative. There was positive correlation of fruit infestation with yield (q/acre) and positive and non-significant correlation with number of primary branches/plant with r –value 0.661 and 0.319, respectively. Additionally, various management techniques were tested individually and in different combinations for the management of L. orbonalis. The integration of Trichogrammachilonis, hoeing and clipping of infested plant parts reduced fruit infestation to the maximum level (5.61, 6.14 and 6.66%) and maximum increase in yield (q/acre) (42.58, 35.99 and 39.29) at research farm PMAS Arid Agriculture University Rawalpindi, vegetable research farm NARC, Islamabad and Usman Khattar Vegetable Farm Taxila, Rawalpindi, respectively against L. orbonalis fruit infestation. Conclusively, the resistant cultivar “Nirala” and integration of different non chemical techniques (Trichogramma chilonis + hoeing + clipping) were recommended for the management of L. orbonalis in brinjal fields.