Wednesday, June 11, 2008

Impact of Resource Conservation Technologies for Sustainability of Irrigated Agriculture in Punjab-Pakistan

Muhammad Rafiq Akhtar
Director, Agricultural Information, Punjab, Lahore (Pakistan).

Abstract
Pakistan is rightly proclaimed as an agricultural country. Agriculture is the largest commodity producing sector and mainstay of the country’s economy. Wheat as a main staple food crop of Pakistan is grown on about 8 million hectares every year. It is a Rabi (winter) crop and replaces rice and cotton in rice-wheat and cotton-wheat systems, respectively. Rice and cotton is grown on 2.4 and 2.9 million hectares every year, respectively. Pakistan’s population is increasing at an alarming pace and it has reached to about 150 million already. Resultantly, with the exception of few years, Pakistan had to import wheat from international market on expense of huge foreign exchange to meet food requirements of its burgeoning population. It is, therefore, imperative to enhance wheat yield by encouraging farmers, predominantly small farmers, to grow more wheat
with efficient and judicious use of land and water resources. Land and water resources especially for agricultural purposes are getting scarce day by day due to mismanagement. This water deficient scenario is also posing serious threats to food security for generations to come. A shift in the production techniques intervening flooded irrigation methods for efficient utilization of resources is being recommended and same has been actively adopted in many courtiers of South Asia. The resource conservation technologies (RCTs) mainly include bed planting of wheat, sowing of wheat following zero tillage technology, bed and furrow sowing of cotton and management of crop residues. Laser land leveling adopted in Pakistan has shown encouraging results under zero tillage technique wheat is sown using residual moisture with no or minimum tillage without irrigating the fields with the aim to sow wheat in time after rice, conservation of water, and reduced cultivation cost. The technology has been adopted on about one million hectares and presently farmers own more than 5,000 zero tillage drills. Similarly, crops especially cotton is being planted on the raised beds to minimize water losses caused in the flood irrigations. Although these technologies are being adopted on wide scale, yet some quarters are still showing their concerns regarding weed control, pest management and impact on soil structure in relation to adoption of such technology in rice-wheat system of the Punjab. Other faction of scientists/experts is advocating adoption of zero tillage in the country because of embedded benefits of these technologies; for example, efficient use of water and other inputs, cost effectiveness compared to conventional methods of sowing, reduced consumption of diesel and above all, advancement of planting date of wheat by reducing turn around time between wheat sowing and successive rice crop. Latest dimensions of zero tillage and bed planting are also being highlighted in favour of this technology including improving soil biodiversity, reduced air pollution, mitigation of environmental degradation after residue burning, and carbon sequestration.

Keywords: Irrigated farming; sustainability; resource conservation; productivity; Punjab; Pakistan.
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Effects of Storage of Bananas in Controlled Atmosphere Before Ethylene Treatments on Its Ripening and Quality

Saeed Ahmad
Ph.D. Study, Cranfield University, UK.,
M. A. Perviez
Assistant Research Officer,
A. K. Thompson
Institute of Horticultural Sciences, University of Agriculture Faisalabad.,

and Hammed Ullah
Citrus Research Station, Sahiwal.

Abstract
The study was conducted in Post Harvest Laboratory, Cranfield University at Silsoe College, UK during 1999. The objective was to investigate whether ripening processes in banana fruits which are depressed in reduced O2 and increased CO2 storage for two weeks, could be initiated with ethylene treatment and produce good quality ripe fruit like control. It was observed that ethylene treatment became dominant over the inhibition effect of controlled atmosphere storage when bananas were removed to normal air. All bananas including control reached colour stage 6 after 9 days of ethylene treatment. Bananas exhibited the lowest weight loss at 2 percent O2 with 8, 6 and 4 percent CO2 while the control showed higher percentage of weight loss during storage. The trend of weight loss was changed during ripening which was less in storage conditions but it increased with ethylene treatments. The total weight loss (storage + ripening) was greater (5.48%) in control and it was lower (4.71, 4.54 and 4.68%) in storage at 2 percent O2 with three levels of CO2. Controlled atmosphere storage showed no effect on total soluble solids. Bananas stored at 2 percent O2 with 4, 6 and 8 percent CO2 produced firm bananas (3.48, 5.51 and 3.54 values N/mm). Firm and ripe bananas could be less susceptible to mechanical injury and some fungal diseases.

Keywords: Bananas; controlled atmosphere storage; oxygen; carbon dioxide; chlorothalonil; United Kingdom.
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Green Fodder Yield Performance of Oats Varieties Under Irrigated Conditions

Muhammad Naeem
Senior Scientific Officer, National Cooperative Research Programme on Fodder Crops,
Muhammad Shahid Munir Chohan, Ahmad Hassan Khan
Assistant Research Officer,

and Riaz Ahmad Kainth
Assistant Botanist, Fodder Research Sub-Station,
AyubAgricultural Research Institute, Faisalabad, Pakistan.

Abstract
Nine varieties of oats and a check were evaluated during rabi season 2002-03 at Fodder Research Sub-station, Ayub Agricultural Research Institute, Faisalabad. Significant differences were observed for plant height, number of tillers per meter row and green fodder yield while differences for number of leaves per tiller and leaf area were non-significant. The variety S-81 was the tallest (103.33 cm) while check variety PD2 LV65 the shortest (86 cm). Number of tillers per meter row varied from 79 (check PD2 LV65) to 106.67 (S-81) while number of leaves per tiller ranged from 7.89 (PD2 LV65) to 9 (S-81, Scott, No.708 and S-2000). Leaf area varied from 70.38 (No.681) to 84.96 cm2 (Scott) while green fodder yield ranged from 49.36 (check PD2 LV65) to 69.44 tons per hectare (S-81). Varieties Scott and No.708 ranked second by producing identical green fodder yield (66.98 t/ha) followed by No.677 (66.67 t/ha), S-2000 (65.43 t/ha) and No.681 (63.89 t/ha).

Keywords: Avena sativa; high yielding varieties; agronomic characters; performance; Pakistan.
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Comparison of some Advanced Lines of Sorghum Bicolor L. Monech for Green Fodder/Dry Matter Yields and Morpho-Economic Parameters

Chaudhry Ghulam Nabi, Muhammad Riaz and Ghulam Ahmad
Fodder Research Institute, Sargodha, Pakistan.


Abstract
These studies were conducted at Fodder Research Institute, Sargodha during the year 1999-2001. Five cultivars of sorghum including check (Hegari) were evaluated for plant height, stem thickness, leaf area, number of leaves per plant, sweetness, crude protein, green fodder and dry matter yields. Cultivar JS-88 showed significant differences with higher number of leaves per plant (13.5), stem thickness (1.8 cm) and leaf area (512.5 cm2) as compared to check (10.6 average number of leaves/plant, 1.3 cm stem thickness and 445.5 cm2 leaf area). Similarly, JS-88 was superior in green fodder yield, dry matter yield and quality (sweetness and crude protein) to Hegari. On an average JS-88 produced 73.8 tons per hectare green fodder and 12.8 tons per hectare dry matter yield as compared to Hegari (59.6 t/ha green fodder yield and 8.4 t/ha dry matter yield). Early growth stages had high crude protein level than late stages.

KEYWORDS: Sorghum bicolor; high yielding varieties; agronomic characters; Pakistan.
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The predictive power of the European Economic Sentiment Indicator

Sarah Gelper and Christophe Croux

Abstract
Economic sentiment surveys are carried out by all European Union member states on a monthly basis. The survey outcomes are used to obtain early insight into future economic evolutions and often receive extensive press coverage. Based on these surveys, the European Commission constructs an aggregate European Economic Sentiment Indicator (ESI). This paper compares the ESI with more sophisticated aggregation schemes based on two statistical methods: dynamic factor analysis and partial least squares. We compare the aggregate sentiment indicators and the weights used in their construction. Afterwards a comparison of their forecast performance for two real economic series, industrial production growth and unemployment, follows. Our findings are twofold. First it is found that the ESI, although constructed in a rather ad hoc way, can compete with the indicators constructed according to statistical principles. Secondly, the predictive power of the sentiment indicators, as tested for in an out-of sample Granger causality framework, is limited.

Keywords: Common indicators; Dimension reduction methods; Economic sentiment indicator; Forecasting.

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Modeling a healthcare system as a queueing network:The case of a Belgian hospital

Creemers S and Lambrecht MR

Abstract
The performance of health care systems in terms of patient flow times and utilization of critical resources can be assessed through queueing and simulation models. We model the orthopaedic department of the Middelheim hospital (Antwerpen, Belgium) focusing on the impact of outages (preemptive and nonpreemptive outages) on the effective utilization of resources and on the flowtime of patients. Several queueing network solution procedures are developed such as the decomposition and Brownian motion approaches. Simulation is used as a validation tool. We present new approaches to model outages. The model offers a valuable tool to study the trade-off between the capacity structure, sources of variability and patient flow times.

Keywords: Belgium; Brownian motion; Capacity management; Decomposition; Health care; Healthcare; Impact; Model; Models; Performance; Performance measurement; Queueing; Queueing theory; Simulation; Stochastic processes; Structure; Studies; Systems; Time; Tool; Validation; Variability.
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Brecht Cardoen, Erik Demeulemeester, Jeroen BeliÄen
Katholieke Universiteit Leuven, Faculty of Economics and Applied Economics, Department of Decision Sciences and Information Management,
Naamsestraat 69, B-3000 Leuven, Belgium,

Abstract
In this paper we will investigate how to sequence surgical cases in a day-care facility so that multiple objectives are simultaneously optimized. The limited availability of resources and the occurrence of medical precautions, such as an additional cleaning of the operating room after the surgery of an infected patient, are taken into account. A branch-and-price methodology will be introduced in order to develop both exact and heuristic algorithms. In this methodology, column generation is used to optimize the linear programming formulation of the scheduling problem. Both a dynamic programming approach and an integer programming approach will be specified in order to solve the pricing problem. The column generation procedure will be combined with various branching schemes in order to guarantee the integrality of the solutions. The resulting solution procedures will be thoroughly tested and evaluated using real-life data of the surgical day-care center at the university hospital Gasthuisberg in Leuven (Belgium). Computational results will be summarized and conclusions will eventually be formulated.

Keywords: Branch-and-price; Column generation; Health care operations; Scheduling.

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Key words: Customer lifetime value; Value; Yield; Companies; Order; Model; Product; Expected

Boute R, Lambrecht MR, Lambrechts O and Sterckx P
Abstract: Various inventory studies have been published in the last decades. Some studies emphasize the importance of low inventories, other examine the evolution of inventories over time and especially focus on the impact of the just-in-time (JIT) revolution. The aim of this paper is to investigate the level of inventories held by Belgian companies at one moment in time, namely May 2004. First we examine differences in inventory ratios between manufacturing industry sectors as well as between wholesale and retail. We find empirical evidence that the type of production process is the most important driver for work in process inventory. The finished goods inventory ratio also differs significantly among industry sectors, but here the reasons for the difference are harder to distinguish. Finally we find the inventory ratio to be significantly higher in retail than in wholesale. Furthermore, we examine the financial impact of inventories in the manufacturing industry. We find that companies with very high inventory ratios have more chance to be bad financial performers. Regression analyses partially support the hypothesis of a negative relationship between inventory ratio and financial performance but significant results could not be obtained for all sectors.

Key words: Inventory; Manufacturing
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A Modified Pareto/NBD Approach for Predicting Customer

Nicolas Glady, Bart Baesens and Christophe Croux
Faculty of Economics and Management, K.U.Leuven
School of Management, University of Southampton
Abstract
Valuing customers is a central issue for any commercial activity. The customer lifetime value (CLV) is the discounted value of the future profits that this customer yields to the company. In order to compute the CLV, one needs to predict the future number of transactions a customer will make and the pro¯t of these transactions. With the Pareto/NBD model, the future number of transactions of a customer can be predicted, and the CLV is then computed as a discounted product between this number and the expected profit per transaction. Usually, the number of transactions and the future profits per transaction are estimated separately. This study proposes an alternative. We show that the dependence between the number of transactions and
their probability can be used to increase the accuracy of the prediction of the CLV. This is illustrated with a new empirical case from the retail banking sector.
Keywords: Customer lifetime value; Value; Yield; Companies; Order; Model; Product; Expected.
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Sums and Products of Jointly Distributed Random Variables: A Simplified Approach

Sheldon H. Stein
Cleveland State University
Journal of Statistics Education Volume 13, Number 3 (2005),
Abstract
Three basic theorems concerning expected values and variances of sums and products of random variables play an important role in mathematical statistics and its applications in education, business, the social sciences, and the natural sciences. A solid understanding of these theorems requires that students be familiar with the proofs of these theorems. But while students who major in mathematics and other technical fields should have no difficulties coping with these proofs, students who major in education, business, and the social sciences often find it difficult to follow these proofs. In many textbooks and courses in statistics which are geared to the latter group, mathematical proofs are sometimes omitted because students find the mathematics too confusing. In this paper, we present a simpler approach to these proofs. This paper will be useful for those who teach students whose level of mathematical maturity does not include a solid grasp of differential calculus.
Keywords: Covariance; Joint probability distribution; Means; Variances.
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Characteristics and Performance of Students in an Online Section of Business Statistics

John Dutton
North Carolina State University

Marilyn Dutton
North Carolina Central University
Journal of Statistics Education Volume 13, Number 3 (2005),
Abstract
We compare students in online and lecture sections of a business statistics class taught simultaneously by the same instructor using the same content, assignments, and exams in the fall of 2001. Student data are based on class grades, registration records, and two surveys. The surveys asked for information on preparedness, reasons for section choice, and evaluations of course experience and satisfaction. Using descriptive statistics, regression analysis and standard hypothesis tests, we test for significant differences between the online and lecture sections with regard to performance and satisfaction with the course as well as motivation and preparedness for taking an online course. We report several differences, including better performance by online students.
Keywords: Distance education; Internet course; Online education.
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Demonstration of Ranking Issues for Students: A Case Study

I. Elaine Allen
Babson College

Norean Radke Sharpe
Babson College
Journal of Statistics Education Volume 13, Number 3 (2005),
Abstract
This article uses a case study of 2001 town and city data that we analyzed for Boston Magazine. We use this case study to demonstrate the challenges of creating a valid ranking structure. The data consist of three composite indices for 147 individual townships in the Boston metropolitan area representing measures of public safety; the environment; and health. We report the data and the basic ranking procedure used in the magazine article, as well as a discussion of alternative ranking procedures. In particular, we demonstrate the impact of additional adjustment for the size of population, even when per capita data are used. This case study presents an opportunity for discussion of fundamental data analysis concepts in all levels of statistics courses.
Keywords: Data Analysis; Demographics; Graphics; Rank methods.
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Building the Numeracy Skills of Undergraduate and Elementary School Students

Pam Boger
Ohio University
Journal of Statistics Education Volume 13, Number 3 (2005),
Abstract
This paper describes a project with the goal of exposing both elementary school and undergraduate students to the concepts associated with the experimental method, from the formulation of a researchable question to the analysis and interpretation of the results. Under the guidance of their university mentors, fourth and fifth grade students formulated a research question, designed an experiment to answer that inquiry, recorded the appropriate measurements, calculated the necessary statistics, created visual displays of their results, and interpreted their findings at a student-centered Numeracy Conference.
Keywords: Active learning; Elementary statistics education, Numeracy.
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4 out of 5 Students Surveyed Would Recommend this Activity (Comparing Chewing Gum Flavor Durations)

Mary Richardson
Grand Valley State University

Neal Rogness
Grand Valley State University

Byron Gajewski
The University of Kansas Medical Center
Journal of Statistics Education Volume 13, Number 3 (2005),
Abstract
This paper describes an interactive activity developed for illustrating hypothesis tests on the mean for paired or matched samples. The activity is extended to illustrate assessing normality, the Wilcoxon signed rank test, Kaplan-Meier survival functions, two-way analysis of variance, and the randomized block design.
Keywords: Active learning; Assessing normality; Blinding; Confounding variable; Kaplan-Meier survival function; Paired difference experiment; Randomization; Randomized block design; Right-censored data; Two-way analysis of variance; Wilcoxon signed rank test.
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Teaching an Introductory Statistics Course with CyberStats, an Electronic Textbook

Jürgen Symanzik and Natascha Vukasinovic
Utah State University
Journal of Statistics Education Volume 14, Number 1 (2006),
Abstract
In the Fall 2001 semester, we taught a “Web-enhanced” version of the undergraduate course “Statistical Methods” (STAT 2000) at Utah State University. The course used the electronic textbook CyberStats in addition to “face-to-face” teaching. This paper gives insight in our experiences in teaching this course. We describe the main features of CyberStats, the course content and the teaching techniques used in class, students' reactions and performance, and some specific problems encountered during the course. We compare this Web-enhanced course with other similar textbook-based courses and report instructors' and students' opinions. We finish with a general discussion of advantages and disadvantages of a Web-enhanced statistics course.
Keywords: Key Words: Computer; Interactivity; Statistical Concepts; Undergraduate Course; Web-enhanced Course.
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Advice for New and Student Lecturers on Probability and Statistics

Michael D. Larsen
Iowa State University
Journal of Statistics Education Volume 14, Number 1 (2006),
Abstract
Lecture is a common presentation style that gives instructors a lot of control over topics and time allocation, but can limit active student participation and learning. This article presents some ideas to increase the level of student involvement in lecture. The examples and suggestions are based on the author’s experience as a senior lecturer for four years observing and mentoring graduate student instructors. The ideas can be used to modify or augment current plans and preparations to increase student participation. The ideas and examples will be useful as enhancements to current efforts to teach probability and statistics. Most suggestions will not take much class time and can be integrated smoothly into current preparations.
Keywords: Active learning; Contrasts; Problem Solving; Statistical Reasoning; Student Participation; Teaching Methods.
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There Once Was a 9-Block ...- A Middle-School Design for Probability and Statistics

Dor Abrahamson
University of California, Berkeley

Ruth M. Janusz
Nichols Middle School, Evanston, IL

Uri Wilensky
Northwestern University

Journal of Statistics Education Volume 14, Number 1 (2006),
Abstract
ProbLab is a probability-and-statistics unit developed at the Center for Connected Learning and Computer-Based Modeling, Northwestern University. Students analyze the combinatorial space of the 9-block, a 3-by-3 grid of squares, in which each square can be either green or blue. All 512 possible 9-blocks are constructed and assembled in a “bar chart” poster according to the number of green squares in each, resulting in a narrow and very tall display. This combinations tower is the same shape as the normal distribution received when 9-blocks are generated randomly in computer-based simulated probability experiments. The resemblance between the display and the distribution is key to student insight into relations between theoretical and empirical probability and between determinism and randomness. The 9-block also functions as a sampling format in a computer-based statistics activity, where students sample from a “population” of squares and then input and pool their guesses as to the greenness of the population. We report on an implementation of the design in two Grade 6 classrooms, focusing on student inventions and learning as well as emergent classroom socio-mathematical behaviors in the combinations-tower activity. We propose an application of the 9-block framework that affords insight into the Central Limit Theorem in science.
Keywords: Computers; Education; Mathematics; Sample; Statistics.
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