• Title/Summary/Keyword: Fractional factorial designs

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A Conjoint-Based Approach to Analyze the Importance of Brand Choice Attributes: Pizza Restaurant Cases (컨조인트 분석을 통한 피자 브랜드 선택 속성의 중요도 분석)

  • 양일선;채인숙;이민아;신서영;차진아
    • Korean Journal of Community Nutrition
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    • v.7 no.3
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    • pp.354-360
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    • 2002
  • The purposes of this study were (1) to understand how customers trade off one attribute against another when they choose a pizza restaurant, (2) to compare the importance of individual attributes with their relative importance and (3) to compare customers'brand choice patterns with the prediction of pizza restaurant operators. Empirical data for this study were collected from the customers (n=307) and operators (n=273) of flour famous pizza franchise restaurants in Korea, Pizza Hut, Mister Pizza, Domino's Pizza and Pizza Mall. The attributes and attribute levels for the hypothetical profiles were decided from the focus group discussion. A total of 16 profiles was selected from fractional factorial designs. The SPSS conjoint procedure was used to calculate utility scores and simulate profiles. The overall group statistics showed the relative importance of all attributes compared with one other. Taste was the most important attribute (32.48%) in choosing a pizza restaurant, followed by service (21.87%) , atmosphere (17.23%), price (15.17%) and speed of delivery (13.26%). There was a difference between the customers'ratings of the importance of the individual attributes and the ranking of the same attributes'relative importance as derived from the conjoint analysis. The operators rated service (26.54%) as also being important, as well as taste (27.76%), in choosing a pizza restaurant. The rankings of relative importance for pizza taste, service and price were statistically different in the customers'and operators'data (p < 0.001, p < 0.1, p < 0.5). Operators who want to differentiate themselves from their competitors should make decisions based on an increased understanding of their customers'brand choice decision process and measure the hidden needs of their customers.

Analyzing the Importance of Tourists' Restaurant Choice Attributes in Tourism Provinces (강원 동해안 관광객의 외식점포 선택속성의 중요도 분석)

  • Chae, In-Sook;Lee, So-Jung
    • Journal of the Korean Home Economics Association
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    • v.46 no.5
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    • pp.63-71
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    • 2008
  • The purposes of this study were (1) to analyze the absolute and relative importance of tourists' choice attributes of restaurants and (2) to compare tourists' choice patterns with the prediction of restaurant operators in the tourism provinces of Gangwon-do, Empirical data for this study were collected from the 77 tourists and 66 restaurants operators. The attributes and attribute levels for the hypothetical profiles were decided from a focus group interview and 15 profiles were selected from fractional factorial designs. The SPSS/WIN 12,0 conjoint procedure was used to calculate the utility scores and simulate the profiles, According to the analysis on the relative importance of tourists' choice attributes of restaurants, food taste was the most important attribute(36.9%), followed by facility cleanliness(28.5%), dishes cleanliness(24.5%), price(19.3%) and service(18.3%). The tourists' ratings of the importance of the individual attributes differed from the ranking of the relative importance of the same attributes as derived from the conjoint analysis. The operators rated dishes cleanliness(27.6%) as also important, followed by food taste(27.7%), in choosing a restaurant Tourists' preference and operators' prediction of hypothetical profiles showed significant difference in L(p < .05), O(p < .01), M(p < .05), and H(p < .01) restaurants. Operators who want to differentiate themselves from their competitors should make decisions based on an increased understanding of tourists' restaurant choice decision process and measure the latent needs of tourists in the tourism provinces.

Statistical Optimization of Solid Growth-medium for Rapid and Large Screening of Polysaccharides High-yielding Mycelial Cells of Inonotus obliquus (단백다당체 고생산성의 Inonotus obliquus 균주의 신속 개량을 위한 고체 성장배지의 통계적 최적화)

  • Hong, Hyung-Pyo;Jeong, Yong-Seob;Chun, Gie-Taek
    • KSBB Journal
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    • v.25 no.2
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    • pp.142-154
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    • 2010
  • The protein-bound innerpolysaccharides (IPS) produced by suspended mycelial cultures of Inonotus obliquus have promising potentials as an effective antidiabetic as well as an immunostimulating agents. To enhance IPS production, intensive strain improvement process should be carried out using large amount of UV-mutated protoplasts. During the whole strain-screening process, the stage of solid growth-culture was found to be the most time-requiring step, thus preventing rapid screening of high-yielding producers. In order to reduce the cell growth period in the solid growth-stage, therefore, solid growth-medium was optimized using the statistical methods such as (i) Plackett-Burman and fractional factorial designs (FFD) for selecting positive medium components, and (ii) steepest ascent (SAM) and response surface (RSM) methods for determining optimum concentrations of the selected components. By adopting the medium composition recommended by the SAM experiment, significantly higher growth rate was obtained in the solid growth-cultures, as represented by about 41% larger diameter of the cell growth circle and higher mycelial density. Sequential optimization process performed using the RSM experiments finally recommended the medium composition as follows: glucose 25.61g/L, brown rice 12.53 g/L, soytone peptone 12.53 g/L, $MgSO_4$ 5.53 g/L, and agar 20 g/L. It should be noted that this composition was almost similar to the medium combinations determined by the SAM experiment, demonstrating that the SAM was very helpful in finding out the final optimum concentrations. Through the use of this optimized medium, the period for the solid growth-culture could be successfully reduced to about 8 days from the previous 15~20 days, thus enabling large and mass screening of high producers in a relatively short period.