scholarly journals Visualization and Quantitative Assessment to Verify Precipitation Forecasts Associated with Mid-Latitude Cyclones across the Eastern United States

2021 ◽  
pp. 1-13
Author(s):  
J. Williams ◽  
M.C Hung ◽  
Y.H. Wu
Keyword(s):  
Hypothesis Test ◽  
Spatial Relation ◽  
False Alarms ◽  
Eastern United States ◽  
Forecast System ◽  
Forecast Data ◽  
Working Together ◽  
Gfs Model ◽  
The Mean ◽  
Spatial Verification

Analysis was conducted to verify forecast against observation precipitation associated with mid-latitude cyclones over the Eastern US in winter and spring 2013 using Geographic Information Systems (GIS). The forecast data are day two 24-hour Quantitative Precipitation Forecasts (QPF) produced by the Global Forecast System (GFS) model. The analysis methods produced categorical geographic error maps of hits, misses and false alarms in spatial relation to the mid-latitude cyclones and traditional verification scores for each day. A hypothesis test was also performed to determine if the GFS mean forecast precipitation over the study area is significantly different from the mean observed precipitation during mid-latitude cyclones. The spatial verification maps, as an analytical and visualization tool, provided evidences on geographical relationship between correct predictions (hits and correct negatives) and incorrect predictions (misses and false alarms). Working together with quantitative scores and hypothesis test, spatial verification maps reveal that the GFS model has a tendency to over forecast precipitation coverage associated with mid-latitude cyclones over the Eastern US and often moves the mid-latitude cyclones too fast.

EFFECTIVENESS OF PROBLEM BASED LEARNING MODEL (PBL) SETTING OPEN ENDED APPROACH IN MATHEMATICS LEARNING

2017 ◽  
Vol 5 (3) ◽  
pp. 418
Author(s):  
Muhammad Nur Sabar
Keyword(s):  
Teaching And Learning ◽  
Hypothesis Test ◽  
Mathematics Learning ◽  
Problem Based Learning ◽  
Sampling Technique ◽  
High Category ◽  
Class Viii ◽  
The Mean ◽  
Normalized Gain ◽  
Pbl Model

The study aims at examining (1) the effectiveness of the implementation of Problem Based Learning (PBL) model using Open Ended approach, (2) the students’ learning result in mathematics who were taught by using PBL model with Open Ended approach, (3) the students’ activities in teaching and learning process by using PBL model with Open Ended approach, and (4) the students’ response on learning. The study is pre-experiment research with One Group Pretest-Posttest Design. The populations of the study were class VIII students at SMPN 33 Makassar of academic year 2016/2017 wich consisted of 10 classes. Samples were selected by employing Cluster Random Sampling technique and obtained class VIIIE as the research sample. Data were obtained by using learning result test instrument, observation sheet of students’ activities, observation sheet of learning implementation, and questionnaire of students’ response. The results of the study reveal that the learning result score of class VIII students in mathematics I sin high category, the mean 83.22, and deviation standar 8.549, the classical completeness is 87.50%, the mean of normalized gain is in high category, the students’ activity is in very active category, and students’ response on the implementation of PBL model with Open Ended approach is positive. The result of hypothesis test indicates that PBL model with Open Ended approach is effective to implemented in Mathematics learning to class VIII students at SMPN 33 Makassar. 

scholarly journals The Effect of Using Genre-Based Approach towards Students’ Writing Skill on Recount Text

2021 ◽  
Vol 1 (2) ◽  
pp. 56-61
Author(s):  
Devia Della Dhika ◽  
Muhammad Sulhan
Keyword(s):  
Standard Deviation ◽  
Hypothesis Test ◽  
Writing Skill ◽  
Quantitative Design ◽  
The Mean

The research aims at determining the effect of using Genre-Based Approach towards students’ skill on writing recount text at SMP PGRI 9 East Jakarta. It uses quantitative design by giving treatment of the application of Genre-Based Approach to the experiment class. The population was all students of eight graders at SMP PGRI 9 East Jakarta and was taken 50 of them as the samples. They were divided into two classes; the experiment class consists of 25 students and the control class consists of 25 students. The result shows that the mean of the control class is 69.78, the median is 70, and the mode is 65.94 with standard deviation values is 7.63. While, the mean of the experiment class is 81.06, the median is 81.35 and the mode is 101.5 with standard deviation values is 10.1. The Fobserved is 1.78 < Ftable 1.98, meaning that both classes are homogenous. The hypothesis test tobserved is 4.44 > ttable 2.01, which means that H1 is accepted which confirms there is an effect of using Genre-Based Approach towards students’ writing skill on recount text at SMP PGRI 9 East Jakarta.

scholarly journals High-Resolution Ensemble HFV3 Forecasts of Hurricane Michael (2018): Rapid Intensification in Shear

2020 ◽  
Vol 148 (5) ◽  
pp. 2009-2032 ◽  
Author(s):  
Andrew T. Hazelton ◽  
Xuejin Zhang ◽  
Sundararaman Gopalakrishnan ◽  
William Ramstrom ◽  
Frank Marks ◽  
...  
Keyword(s):  
Tropical Cyclones ◽  
Early Stage ◽  
Vertical Wind Shear ◽  
Vertical Shear ◽  
Rapid Intensification ◽  
Forecast System ◽  
The Mean ◽  
Cubed Sphere ◽  
Environmental Prediction ◽  
The Relationship

Abstract The FV3GFS is the current operational Global Forecast System (GFS) at the National Centers for Environmental Prediction (NCEP), which combines a finite-volume cubed sphere dynamical core (FV3) and GFS physics. In this study, FV3GFS is used to gain understanding of rapid intensification (RI) of tropical cyclones (TCs) in shear. The analysis demonstrates the importance of TC structure in a complex system like Hurricane Michael, which intensified to a category 5 hurricane over the Gulf of Mexico despite over 20 kt (10 m s−1) of vertical wind shear. Michael’s RI is examined using a global-nest FV3GFS ensemble with the nest at 3-km resolution. The ensemble shows a range of peak intensities from 77 to 159 kt (40–82 m s−1). Precipitation symmetry, vortex tilt, moisture, and other aspects of Michael’s evolution are compared through composites of stronger and weaker members. The 850–200-hPa vertical shear is 22 kt (11 m s−1) in the mean of both strong and weak members during the early stage. Tilt and moisture are two distinguishing factors between strong and weak members. The relationship between vortex tilt and humidification is complex, and other studies have shown both are important for sheared intensification. Here, it is shown that tilt reduction leads to upshear humidification and is thus a driving factor for intensification. A stronger initial vortex and early evolution of the vortex also appear to be the key to members that are able to resist the sheared environment.

scholarly journals Disclosure Dynamics and Investor Learning

2020 ◽  
Author(s):  
Frank S. Zhou
Keyword(s):  
Capital Market ◽  
Earnings Forecast ◽  
Management Forecast ◽  
Disclosure Decisions ◽  
Forecast Data ◽  
The Mean ◽  
Investor Learning ◽  
Market Consequences ◽  
Period Model ◽  
The Capital Market

This paper examines whether investor learning about profitability (i.e., the mean of earnings distribution) leads to persistence in disclosure decisions. A repeated single-period model shows that persistent investor beliefs about profitability lead to persistent disclosure decisions. Using earnings forecast data, I structurally estimate the model and perform several counterfactual analyses. I find that, when investors are assumed to know profitability, the persistence of management forecast decisions significantly declines by 17%–27%. About 24% of firms would have disclosed differently, resulting in 3.9% net change in the amount of information (i.e., posterior variance) provided to the capital market. Collectively, the results indicate the importance of learning profitability in understanding disclosure decisions and the capital market consequences of disclosures. This paper was accepted by Shiva Rajgopal, accounting.

scholarly journals Forecasting the Maintenance of Mesoscale Convective Systems Crossing the Appalachian Mountains

2010 ◽  
Vol 25 (4) ◽  
pp. 1179-1195 ◽  
Author(s):  
Casey E. Letkewicz ◽  
Matthew D. Parker
Keyword(s):  
Appalachian Mountains ◽  
Severe Weather ◽  
Mesoscale Convective Systems ◽  
Radiosonde Data ◽  
Eastern United States ◽  
Unique Problem ◽  
Convective Systems ◽  
Barrier Analysis ◽  
Mesoscale Convective ◽  
The Mean

Abstract Forecasting the maintenance of mesoscale convective systems (MCSs) is a unique problem in the eastern United States due to the influence of the Appalachian Mountains. At times these systems are able to traverse the terrain and produce severe weather in the lee, while at other times they instead dissipate upon encountering the mountains. To differentiate between crossing and noncrossing MCS environments, 20 crossing and 20 noncrossing MCS cases were examined. The cases were largely similar in terms of their 500-hPa patterns, MCS archetypes, and orientations with respect to the barrier. Analysis of radiosonde data, however, revealed that the environment east of the mountains discriminated between case types very well. The thermodynamic and kinematic variables that had the most discriminatory power included those associated with instability, several different bulk shear vector magnitudes, and also the mean tropospheric wind. Crossing cases were characterized by higher instability, which was found to be partially attributable to the diurnal cycle. However, these cases also tended to occur in environments with weaker shear and a smaller mean wind. The potential reasons for these results, and their forecasting implications, are discussed.

scholarly journals Verification of Extratropical Cyclones within the NCEP Operational Models. Part I: Analysis Errors and Short-Term NAM and GFS Forecasts

2009 ◽  
Vol 24 (5) ◽  
pp. 1173-1190 ◽  
Author(s):  
Michael E. Charles ◽  
Brian A. Colle
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
Eastern Pacific ◽  
Extratropical Cyclones ◽  
Global Forecast System ◽  
Eastern United States ◽  
Forecast System ◽  
Short Term ◽  
The North

Abstract This paper verifies extratropical cyclones around North America and the adjacent oceans within the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) and North American Mesoscale (NAM) models during the 2002–07 cool seasons (October–March). The analyzed cyclones in the Global Forecast System (GFS) model, North American Mesoscale (NAM) model, and the North American Regional Reanalysis (NARR) were also compared against sea level pressure (SLP) observations around extratropical cyclones. The GFS analysis of SLP was clearly superior to the NAM and NARR analyses. The analyzed cyclone pressures in the NAM improved in 2006–07 when its data assimilation was switched to the Gridpoint Statistical Interpolation (GSI). The NCEP GFS has more skillful cyclone intensity and position forecasts than the NAM over the continental United States and adjacent oceans, especially over the eastern Pacific, where the NAM has a large positive (underdeepening) bias in cyclone central pressure. For the short-term (0–60 h) forecasts, the GFS and NAM cyclone errors over the eastern Pacific are larger than the other regions to the east. There are relatively large biases in cyclone position for both models, which vary spatially around North America. The eastern Pacific has four to eight cyclone events per year on average, with errors &gt;10 mb at hour 48 in the GFS; this number has not decreased in recent years. There has been little improvement in the 0–2-day cyclone forecasts during the past 5 yr over the eastern United States, while there has been a relatively large improvement in the cyclone pressure predictions over the eastern Pacific in the NAM.

scholarly journals Evaluation of the U.S. Mothbean Collection for Seed Yield Potential in Virginia and Nutritional Composition of Freshly Harvested Seed

2016 ◽  
Vol 26 (6) ◽  
pp. 820-824
Author(s):  
Harbans L. Bhardwaj ◽  
Anwar A. Hamama
Keyword(s):  
United States ◽  
Nutritional Composition ◽  
Yield Potential ◽  
Eastern United States ◽  
Tepary Bean ◽  
Legume Crop ◽  
Iron And Zinc ◽  
The Mean ◽  
Calcium Iron ◽  
Seed Yields

Even though mothbean (Vigna aconitifolia), a drought- and heat-tolerant crop, may have potential in the eastern United States, information about its production in this region is not available. To characterize potential seed yields and preliminary nutritional quality, 54 accessions were grown near Petersburg, VA, during 2011, 2012, and 2013. The seed yields varied from 48 to 413 lb/acre. The mean concentrations of protein, calcium, iron, and zinc in mature mothbean seed were 21.9%, 0.17%, 64.8 ppm, and 37.5 ppm, respectively. These values compared well with those in mungbean (Vigna radiata) and tepary bean (Phaseolus acutifolius). The results demonstrated that mothbean has considerable potential as an alternative, new food legume crop in Virginia and eastern United States.

scholarly journals TRUNK BALANCE EXERCISE LEBIH BAIK DARI PADA STRENGTHENING BACK EXERCISE DALAM MENINGKATKAN KESEIMBANGAN KINERJA OTOT ERECTOR SPINE PADA PEMAIN FUTSAL PEMULA

2017 ◽  
Author(s):  
Yusuf Nasirudin ◽  
Dewa Putu Gde Purwa Samatra ◽  
Wahyuddin ◽  
Susy Purnawati ◽  
Ni Made Linawati ◽  
...  
Keyword(s):  
Hypothesis Test ◽  
Mean Value ◽  
The Body ◽  
Average Value ◽  
Balance Exercise ◽  
Strengthening Exercise ◽  
Significant Difference ◽  
Trunk Balance ◽  
The Mean ◽  
Better Than

In the game of futsal, work of postural muscle balance needed to maintain the stability of the body for receiving the pass and put the ball into the other team's goal at the time of attack, changing the direction of movement quickly when returning to their respective positions and avoid of back disorder. This research is a form of experimental research that will test the effectiveness of the provision of trunk balance exercise is better than the strengthening of back exercises to improve muscle work balance of erector spine on futsal beginner players, in this study sample will be divided into two groups, the first group will be given trunk balance exercise to improve balance of erectorspine muscles work in futsal begginer players, the second group will be given back strengthening exercise to improve balance of erectorspine muscles work in futsal begginer players.This study was conducted for 6 weeks and the intervention performed 18 times during the study period. Samples measured by surface electromyography to measure work of right and left erector muscle by calculating the proportion of the work on the muscle, the measurement is performed at before the intervention and then intervention in accordance with the grouping which has been divided and then after completion of the intervention, the samples will be re-measured to obtain the value of the intervention.The results of the first group who has been given of trunk balance exercise shows the average value of the before treatment (83.82 ± 2.94) % and the mean value of the after treatment (96.74 ± 2.39) %, and in the second group who has been given strengthening back exercise shows the mean value of the before treatment (88.29 ± 1.89) % and the mean value after treatment (95.91 ± 1.75) %, with the probability value of both groups is 0.000 (p <0.05), and can be expressed there is a significant difference between both groups. In the fourth hypothesis test conducted comparative results of both groups, using independent samples t-test using mean value of the first and second groups, in the first group (12.92 ± 2.94) %, and the second group (7.61 ± 2.12) %, with a probability value 0.000 (p<0.05) and can be expressed in statistical analysis is no significant difference between both treatments were carried out and that means, giving trunk balance exercise is better than back strengthening exercise to improve balance of erector spine muscles work on futsal beginner players.

Explorations in statistics: confidence intervals

2009 ◽  
Vol 33 (2) ◽  
pp. 87-90 ◽  
Author(s):  
Douglas Curran-Everett
Keyword(s):  
Confidence Interval ◽  
Confidence Intervals ◽  
Hypothesis Test ◽  
Statistical Information ◽  
Experimental Result ◽  
P Value ◽  
Population Parameter ◽  
True Value ◽  
Level Of Confidence ◽  
The Mean

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This third installment of Explorations in Statistics investigates confidence intervals. A confidence interval is a range that we expect, with some level of confidence, to include the true value of a population parameter such as the mean. A confidence interval provides the same statistical information as the P value from a hypothesis test, but it circumvents the drawbacks of that hypothesis test. Even more important, a confidence interval focuses our attention on the scientific importance of some experimental result.

scholarly journals Neighborhood Verification: A Strategy for Rewarding Close Forecasts

2009 ◽  
Vol 24 (6) ◽  
pp. 1498-1510 ◽  
Author(s):  
Elizabeth E. Ebert
Keyword(s):  
High Resolution ◽  
Rainfall Intensity ◽  
Mean Value ◽  
Forecast Performance ◽  
Fractional Coverage ◽  
Optimal Scale ◽  
Verification Methods ◽  
Intercomparison Project ◽  
The Mean ◽  
Spatial Verification

Abstract High-resolution forecasts may be quite useful even when they do not match the observations exactly. Neighborhood verification is a strategy for evaluating the “closeness” of the forecast to the observations within space–time neighborhoods rather than at the grid scale. Various properties of the forecast within a neighborhood can be assessed for similarity to the observations, including the mean value, fractional coverage, occurrence of a forecast event sufficiently near an observed event, and so on. By varying the sizes of the neighborhoods, it is possible to determine the scales for which the forecast has sufficient skill for a particular application. Several neighborhood verification methods have been proposed in the literature in the last decade. This paper examines four such methods in detail for idealized and real high-resolution precipitation forecasts, highlighting what can be learned from each of the methods. When applied to idealized and real precipitation forecasts from the Spatial Verification Methods Intercomparison Project, all four methods showed improved forecast performance for neighborhood sizes larger than grid scale, with the optimal scale for each method varying as a function of rainfall intensity.

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