• Journal of the Korean Statistical Society
• /
• v.23 no.2
• /
• pp.271-292
• /
• 1994

The comparison of statistical experiments with a common parameter and parameter space is discussed using the concept of the Blackwell's sufficiency and the Shannon's entropy. Binomial and censored experiments are considered as applications. The loss of information is studied under teh aggregated experiments and truncated experiments, and summerized in some tables which make it possible to indicate the choice of an appropriate experiment.

• Proceedings of the Korea Technology Innovation Society Conference
• /
• 2015.05a
• /
• pp.105-112
• /
• 2015

• The Journal of Fisheries Business Administration
• /
• v.40 no.2
• /
• pp.27-48
• /
• 2009

The objective of this paper is to estimate consumer's marginal willingness to pay(MWTP) for cold chain system attributes of mackerel using choice experiment questionnaires. The survey data were analyzed by conjoint analysis method with multinominal logit model. The five cold chain system attributes with $2{\sim}4$ attribute levels were considered : low temperature safekeeping of fishing boats, a kind of transport truck and packing box, using degree of low temperature facility in distribution, mackerel price per fish(1kg). At least 827 people were asked to participate in the survey. The major findings and implications of this study can be summarized as follows : The estimated multinominal logit model is statistically significant and the total consumers willingness to pay for the improved cold chain system attributes is 6,476 won (per kg). Compared with the base price(2,500 won/kg), the estimated MWTP is 2.5 times higher than the base price. Therefore, the consumer has a willingness to pay for the fresh and safe fish products, even though more money is paid. To satisfy the consumer's needs, cold chain system is necessary in point of long-term. In this reason, The government's policy support is needed for promoting cold chain system in fishery, and a master plan should be prepared.

• Korean Journal of Organic Agriculture
• /
• v.29 no.1
• /
• pp.25-39
• /
• 2021

The objective of this study is to analyze the value of attributes of agricultural products in school food service using hedonic price model and choice experiment. In the case of potatoes, bean sprouts, and tomatoes, environment-friendly agricultural products rather than conventional ones, and domestic price premiums exist rather than Chungnam. The higher the price, the higher the margin rate. Conventional agricultural products were more profitable than environment-friendly ones, and domestic products were more profitable than Chungnam. In consumer preferences, environment-friendly agricultural products are preferred over conventional agricultural products and local products (Chungnam, Cheonan, Asan) rather than domestic ones. This is the opposite result of the Hedonic price model estimation that Chungnam has a lower price premium than domestic in the case of origin. This study is meaningful by analyzing the attribute value of agricultural products used for school meals in Chungnam and comparing them with the willingness to pay consumers. With the results of this study, it is necessary that discussions on supplementing the value of local products used in Chungnam school food service.

• New & Renewable Energy
• /
• v.18 no.3
• /
• pp.32-42
• /
• 2022

Rapid spread of intermittent renewable energy has amplified the instability and uncertainty of power systems. The Korea Power Exchange (KPX) promoted efficient management by opening the power brokerage market in 2019. By combining small-scale intermittent renewable energy with a flexible facility through the power brokerage market, the KPX aims to develop a virtual power plant system that will allow the conversion of existing intermittent renewable energy into collective power plants. However, the participation rate of renewable power owners in the power brokerage market is relatively low because other markets such as the small solar power contract market or the Korea Electric Power Corporation power purchase agreement are more profitable. In this study, we used a choice experiment to determine the attributes affecting the participation rate in the power brokerage market for 113 renewable power owners and estimate the value of the power brokerage market. According to the estimation results, a low smart meter installation cost, low profit variations, long contract periods, and few clearances increased the probability of participation. Moreover, the average value of the power brokerage market was estimated to be 2.63 million KRW per power owner.

• Journal of the Korean Wood Science and Technology
• /
• v.51 no.4
• /
• pp.283-294
• /
• 2023

Chemical characterization of vinegars obtained from Durian wood (Durio sp.) and their termicidal activity against Coptotermes curvignathus and antifungal activity against Schizophyllum commune were evaluated. The process of pyrolysis produced wood vinegars at three distinct temperature: 350℃, 400℃, and 450℃. To determine their effectiveness against fungal growth, the vinegars were tested using a Petri dish with 1.0%, 2.0%, 3.0%, and 4.0% (v/v) against S. commune. In the experiment, termicidal activities were evaluated using a no-choice test for C. curvignathus with 3.0%, 6.0%, 9.0%, and 12.0% (v/v). The wood vinegar exhibited antitermitic activity to C. curvignathus workers in the no-choice experiment; For vinegar produced at 450℃, a 6% concentration was required to achieve 100% mortality against C. curvignathus. In addition, a 12% vinegar produced at 450℃ resulted in the lowest mass loss of treated filter paper, which was 20.00%. Furthermore, all the wood vinegars exhibited antifungal activities against S. commune at concentration of 2.0%. The dominant chemical components of wood vinegar produced at temperature of 350℃, 400℃, and 450℃ were 2-methoxy-phenol, 4-ethyl-2-methoxy-phenol, 4-ethyl-2-methoxy-phenol, 3.5-dimethoxy-4-hydroxytoluene, and creosol.

• Journal of Korean Society of Transportation
• /
• v.26 no.6
• /
• pp.133-142
• /
• 2008

The term, travel time reliability, refers to variations in journey time that travelers cannot predict. This issue has been one of the main research topics in transport studies. This paper, especially, investigates the value of travel time reliability. The marginal substitution rate method is suggested as the way for the valuation and travelers' stated preference data are collected based on a choice experiment. A mode choice model is estimated using the data surveyed. The parameters of travel costs and travel time reliability from the model are used to calculate the marginal substitution rate that is interpreted as the value of travel time reliability. The value is arranged by travel areas of intercity and urban trips and by journey purposes of working and non-working types. The result of this research is expected to be helpful of conducting more cautious economic feasibility studies of transport schemes.

• Journal of The Korean Association For Science Education
• /
• v.25 no.2
• /
• pp.111-121
• /
• 2005

The purpose of this study was to analyze characteristics of experimental design and evidence choice of the elementary school students in problem solving process related to controlling variable. For this study, 96 6th grade students were selected and tested with Science Reasoning Task. This study revealed that the types of experimental design were categorized as variance of control variable, controlling of causal variable, perfect controlling variable, imperfect controlling variable, variance of all variable. Prior belief had a strong influence on student's experimental design. The types of evidence choice were categorized as perfect controlling variable, controlling causal variable, variance of causal variable. The degree of controlling variable in evidence choice process was much lower than that in experimental design. Most students tended to choose evidence according to prior belief without controlling variable. The results of this study implied that student's prior belief and characteristic of science process skills should be considered to develop program for promoting controlling variable ability.

• FLOWER RESEARCH JOURNAL
• /
• v.19 no.4
• /
• pp.197-201
• /
• 2011

This study was carried out to investigate cut flower quality bulb circumference and cultivars affecting 7 different cultivars to produce high quality cut flower lilies. To determine the effects of bulb circumference on growth and cut flower quality of 7 different cultivars, Lilium oriental hybrid 'Chilli', 'Ismael', 'Medusa', 'Mother's Choice', 'Siberia', 'Sorbonne', and 'Yelloween' were tested. After cut flower quality experiment, the highest 1st flower bud length and cut flower height were 'Medusa' and 'Mother's Choice' respectively. Most plants had over $30^{\circ}$ stem bending angle except for 'Mother's Choice', and 'Ismael'. The study shows that the bigger bulb circumference has the better 1st peduncle diameter, inflorescence length, stem diameter, number of flowers, and fresh weight. Bulb circumference affects the 1st flower bud length, cut flower height and number of flowers. Stem bending angle, however, is affected by neither bulb circumference nor cultivar. In conclusion, growth, cut flower quality and vase life were affected by the bulb circumference rather than cultivar.

• Asia-Pacific Journal of Business
• /
• v.11 no.4
• /
• pp.65-81
• /
• 2020

Purpose - This research aims to investigate how consumers' eco-friendly product choice ratio changes as the benefits of eco-friendly products are framed as (1) non-monetary benefits, (2) monetary gain integrated with the loss or (3) monetary gain segregated from the loss. Design/methodology/approach - A mixed-design, scenario-based choice experiment was conducted. A series of chi-square tests and residual analyses were conducted to analyze the data. Findings - When the monetary gain was larger or slightly smaller than the loss, the participants' eco-friendly product choice ratio was higher when the monetary gain was integrated with the loss than those in the other two conditions. When the monetary gain was significantly smaller than the loss, the participants' eco-friendly product choice ratio was lower when the monetary gain was integrated with the loss than those in the other conditions. The ratio did not differ between the latter two conditions. Research implications or Originality - This research shows that marketers should frame the benefits of eco-friendly products and their costs in different manners depending on the relative magnitudes of them. This research also complements the existing literature by comparing the effectiveness of non-monetary framing of eco-friendly product benefits with that of monetary framing following hedonic editing hypothesis.