• Title/Summary/Keyword: impact test

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A study on the comparison by the methods of estimating the relaxation load of SEM-pile (SEM파일의 이완하중 산정방법별 이완하중량 비교 연구)

  • Kim, Hyeong-Gyu;Park, Eun-Hyung;Cho, Kook-Hwan
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.3
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    • pp.543-560
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    • 2018
  • With the increased development in downtown underground space facilities that vertically cross under a railway at a shallow depth, the demand for non-open cut method is increasing. However, most construction sites still adopt the pipe roof method, where medium and large diameter steel pipes are pressed in to form a roof, enabling excavation of the inside space. Among the many factors that influence the loosening region and loads that occur while pressing in steel pipes, the size of the pipe has the largest impact, and this factor may correspond to the magnitude of load applied to the underground structure inside the steel pipe roof. The super equilibrium method (SEM) has been developed to minimize ground disturbance and loosening load, and uses small diameter pipes of approximately 114 mm instead of conventional medium and large diameter pipes. This small diameter steel pipe is called an SEM pile. After SEM piles are pressed in and the grouting reinforcement is constructed, a crossing structure is pressed in by using a hydraulic jack without ground subsidence or heaving. The SEM pile, which plays the role of timbering, is a fore-poling pile of approximately 5 m length that prevents ground collapse and supports surface load during excavation of toe part. The loosening region should be adequately calculated to estimate the spacing and construction length of the piles and stiffness of members. In this paper, we conducted a comparative analysis of calculations of loosening load that occurs during the press-in of SEM pile to obtain an optimal design of SEM. We analyzed the influence of factors in main theoretical and empirical formulas applied for calculating loosening regions, and carried out FEM analysis to see an appropriate loosening load to the SEM pile. In order to estimate the soil loosening caused by actual SEM-pile indentation and excavation, a steel pipe indentation reduction model test was conducted. Soil subsidence and soil loosening were investigated quantitatively according to soil/steel pipe (H/D).

A Study on the Purpose-in-Life Level in Patients with Traumatic Brain Injury (외상성 뇌 손상 환자의 삶의 목적 수준에 관한 연구)

  • Rho, Seung-Ho;Kim, Sung-Woo
    • Korean Journal of Psychosomatic Medicine
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    • v.7 no.2
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    • pp.184-195
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    • 1999
  • Objectives : As traumatic brain injury(TBI) leaves chronic sequelae in mind and body, the injured patients should rectify the meaning and object that they have pursued in their lives and set up a new purpose in life that they may make the rest of their lives meaningful. This study was designed to investigate the purpose and quality of life levels and the influence of demographic and clinical variables on the levels in the patients with TBI, and to be of some help to their rehabilitation. Methods : In order to assess the purpose in life(PIL) and the quality of life(QOL) levels, Purpose-in-Life Test, Sickness Impact Profile, Quality of Life Index, Head Injury Symptom Ckecklist, and Neurobehavioral Rating Scale were administered to the subjects. The subjects were thirty-two patients with TBI and the same numbered normal controls. The TBI group was composed of 16 to 65 year-aged patients who had received mild or severe TBI at least 12 months before, and the controls were siblings or friends of the patients whose age, sex, and educational level were similar to them. Results : 1) The PIL and QOL levels of the patients with TBI remained significantly lower than that of control group after their symptoms of injury were stabilized(p<.01, p<.01). 2) The mean PIL score of TBI group was $58.8{\pm}23.2$, which was to be regarded as the level of existential vacuum. 3) The PIL level of TBI group was significantly correlated with the QOL level(p <.01). 4) The subgroup with lower PIL level in patients with TBI has significantly higher rate of female than that with higher PIL(p<.05), the PIL level of female patients was significantly lower than that of male patients(p <.05). 5) The significant differences in PIL levels were not found, in which comparison was performed between each pair of subgroups of patients with TBI divided by severity of injury(mild vs severe), marital status(married vs unmarried), and occupational status prior to injury(employed vs unemployed). Conclusion : The PIL of patients with TBI still remained the level of existential vacuum after symptoms of sequelae had been stabilized, The QOL level was also extremely low, and as the PIL level was low the QOL was also low. The demographic and clinical variables except sex did not have influence on the PIL level in brain-injured patients. It is suggested that every patient should admit their mental and physical limitations caused by brain injury and revise their purpose in life for successful rehabilitation.

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The Effect of College students' Perceived Marketing Communication, Value and Consumption Emotion on Store Loyalty in Discount Store (대학생들이 지각하는 종합슈퍼마켓의 마케팅 커뮤니케이션, 가치, 소비감정이 점포충성도에 미치는 영향)

  • Yang, Hoe-Chang;Ju, Yoon-Hwang
    • Journal of Distribution Science
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    • v.10 no.2
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    • pp.19-28
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    • 2012
  • Rapidly growing sales amount and the number of discount stores caused many side effects and sensitive issues in Korea. Because these severe competition due to more expensive cost just like excessive increase in advertising and location selection, and these caused completely ruined small merchants as well as passed on to the consumer. This Study focused on competitiveness of discount store in Korea to the perspective of college students, as explored the relationships between marketing communication and store loyalty. And, examined for two moderating effect, 1) consumers' value separated by hedonic value and utilitarian value between marketing communication and store loyalty, and 2) consumers' value separated by hedonic value and utilitarian value between marketing communication and consumption emotion. Finally, this study examined for mediating effect of consumption emotion between marketing communication and store loyalty. In order to verify the relationship, moderating and mediating effects, data were collected from 130 college students in Whasung, Gyeonggi Province to test theoretical model and its hypotheses. Findings are as followed : First, analysis showed that factors such as advertisement(β =.221, p<.05), publicity(β =.513, p<.01), sales promotion(β =.234, p<.01), word of mouth(β =.627, p<.01) and physical environment(β =.339, p<.01) for marketing communication in the discount store have statistically significant positive effect on store loyalty. But the result of regression analysis for which factors are more impact in marketing communication between store loyalty showed that word of mouth(β =.53, p<.01) is only statistically significant. Second, publicity(β =-.895, p<.05), the sub-dimension of marketing communication shows only statistically significant negative moderating effect on store loyalty. But, the results of the moderating effect of value between marketing communication and consumption emotion verified that utilitarian value show statistically significant, specifically advertisement(β =.294, p<.01), physical environment(β =.418, p<.01), sales promotion(β =.245, p<.01), word of mouth(β =.414, p<.01) and publicity(β =1.137, p<.05), respectively. And hedonic value show statistically significant, specifically advertisement(β =.286, p<.01), physical environment (β =.418, p<.01), sales promotion(β =.236, p<.01) and word of mouth(β =.420, p<.01), respectively. But publicity(β =.145, p=.119) is not statistically significant. Finally, the results verified mediating effect for consumption emotion between all factors for marketing communication and store loyalty showed that factors such as advertisement, publicity, word of mouth and physical environment for marketing communication except sales promotion were statistically significant fully mediated in advertisement, and partially mediated in publicity, word of mouth and physical environment. This testified that the consumption emotion had the most important factor to enhance store loyalty to the perspective of College students. These results can provide important implications and invaluable tips for planning marketing strategies and gaining access to new potential customers. Implications and future research directions are also discussed.

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Postprandial hypoglycemic effects of mulberry twig and root bark in vivo and in vitro (In vivo와 in vitro에서 상지 및 상백피 에탄올추출물이 식후 혈당 상승 억제 조절에 미치는 영향)

  • Park, Soo Yeon;Jin, Bo Ra;Lee, Yu Rim;Kim, You Jin;Park, Jeong Bin;Jeon, Young Hee;Choi, Sang Won;Kwon, Oran
    • Journal of Nutrition and Health
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    • v.49 no.1
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    • pp.18-27
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    • 2016
  • Purpose: Our previous study demonstrated the hypoglycemic effects of mulberry (Morus alba L.) leaf and the underlying mechanisms. Here we explored the potency of mulberry twigs (TW) and root barks (RB) in postprandial hypoglycemic effects in vitro and in vivo. Methods: The major components of TW and RB were determined by high performance liquid chromatography (HPLC). Alpha-glucosidase inhibition and glucose/fructose uptake inhibition in Caco-2 cells were determined for TW, RB, and their major components, followed by an oral sugar tolerance test (OSTT) in streptozotocin-induced diabetic rats. Male Wistar rats were fed a high-fat diet for 2 weeks and then a single dose of streptozotocin (35 mg/kg B.W) was administered by intraperitoneal injection. Rats with fasting blood glucose levels above 126 mg/dL were randomly divided into 5 groups (n = 8/group) for the following treatments by gavage for 4 weeks: vehicle (normal control and diabetic control), 200 mg/kg B.W of TW or RB or 100 mg/kg B.W of oxyresveratrol (OXY). Results: OXY and mulberroside A were identified as the major components of TW and OXY, mongolicin, and kuwanon H for RB. A significant inhibitory activity on ${\alpha}-glucosidase$ was found for TW, RB, and OXY (p = 0.0099). There was a dose-dependent inhibition of TW and RB on the intestinal sugar uptakes in Caco-2 cells, showing a greater impact on fructose compared to glucose. The OSTT showed that TW and RB significantly delayed time to maximal concentration (p = 0.0088) and decreased maximal concentration (p = 0.0043) compared to the control group. Conclusion: These results suggest that TW and RB may have a postprandial hypoglycemic effect, particularly in the case of high fructose or sucrose intake. OXY was suggested as a contributor to the hypoglycemic effect of TW and RB. Further studies are needed for the systemic effect of TW and RB in circulation.

Impact of Health Risk Factors on the Oral Health of Korean Adolescents: Korea Youth Risk Behavior Web-Based Survey, 2013 (우리나라 청소년의 건강위험요인이 구강건강에 미치는 영향)

  • Do, Kyung-Yi
    • Journal of dental hygiene science
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    • v.16 no.3
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    • pp.193-199
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    • 2016
  • The objective of this study was to investigate the relationship between health-risk factors and oral health in Korean adolescents. This cross-sectional study was based on the 9th Korea Youth Risk Behavior Web-Based Survey (2013). The final participation rate in the survey was 96.4%. of a Total of 72,435 adolescents (age, 12~18 years) who had participated in the survey, 66,951 adolescents (33,777 boys and 33,174 girls) were selected for analysis, after excluding those with missing data. The key variables were oral health factors (one or more of the six oral symptoms), general characteristics (five factors), and health-risk factors (five factors). After adjusting for the general characteristics, frequency analysis, ${\chi}^2-test$ using PASW Statistics ver. 18.0, and logistic regression analysis were performed to understand the effects of health risk-factors on the oral symptoms experienced by the study subjects. Subjects who answered 'Yes' for alcohol consumption had a 1.33 times higher risk of experiencing oral symptoms. Further, subjects who smoked were at a 1.2 times higher risk of experiencing oral symptoms. With regard to internet use, the risk of experiencing oral symptoms was 1.25 times higher for subjects who used the internet for 7 hours or more than for those who used it for less than 1 hour. Compared to those subjects who had not experienced violence in school, the odds ratio of subjects who had experienced it 3~4 times was 1.54-fold higher. The study found that health-risk factors were associated with oral symptom experience. Therefore, programs to understand health-risk factors and interventions should be developed for Korean adolescents and provided on a regular basis along with oral health education.

The Influence of Education and Mentoring of Entrepreneurship on the Intentions of Business Start-Up - Focusing on Self-Efficacy and Resilience - (창업교육과 멘토링이 창업의지에 미치는 영향 - 자기효능감과 회복탄력성의 매개효과를 중심으로 -)

  • Kim, Young-tae
    • Journal of Venture Innovation
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    • v.3 no.1
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    • pp.1-26
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    • 2020
  • The purpose of this study is to explore the factors affecting rural experience by applying the unified push-pull-mooring model. The theoretical model is an unified PPM model that introduces new variables based on PPM. The pull factor of the newly introduced variables were reconstructed based on the Schmitt's Experience model and ServQual model. The hypothesis is set as follows. The push factor will have a negative effect on experience satisfaction and the pull factor(experience attributes, service quality)will have a positive effect on experience satisfaction. Also, mooring factors will have a negative effect on experience satisfaction. The research model of this study was tested by structural equation model based on 314 effective questionnaire data. Service quality had a positive effect on experience satisfaction. Mooring factors have a negative effect on experience satisfaction. Push factor and experience attributes factor were analyzed to have a no significance effect on experience satisfaction. These results theoretically test that the mooring factors also have an important effect on the experience satisfaction in the rural experience. Based on the Schmitt's Experience model and ServQual model introduced as a pull factor, the proposed unified PPM model proved to be a useful analysis framework. In practice, it was able to provide implications on what factors should be strategically and marketingly focused to activate the 6th industry experience.This study examined the impact of start-up education and mentoring on the intentions of business start-up, and verified through empirical analysis whether self-efficacy and resilience were mediated between them. The study surveyed 178 people in their 20s to 50s. The result analysis used the IBM SPSS Statistics 21.0 Statistical Package Program. The analysis performed a regression analysis for factor analysis, correlation analysis, and hypothesis verification. Empirical Research Results. First, it was confirmed that start-up education and mentoring affect on the intentions of business start-up. Second, study shows self-efficacy and resilience has an affect on the intentions of business start-up. Third, start-up education and mentoring affect on self-efficacy and resilience. Fourth, self-efficacy and resilience have been proven to be mediated when entrepreneurship education and mentoring affect on the intentions of business start-up. The results of the research proved that start-up education and mentoring provides and acts as a major role in improving the entrepreneurs' willingness when preparing a start-up. Furthermore, the study also shows the importance of start-up education and mentoring as a proactive variable to promote their will to start-up business. In addition, it was confirmed that the self-efficacy investigated in the preceding study translated into the will to start a business. It was particularly meaningful in that it tested the role of resilience, which was mainly studied in new variables, education and psychology.

A Study on the Engineering Behaviour of Prebored and Precast Steel Pipe Piles from Full-Scale Field Tests and Finite Element Analysis (실규모 현장시험 및 유한요소해석을 통한 강관매입말뚝의 공학적 거동에 대한 연구)

  • Kim, Jeong-Sub;Jung, Gyoung-Ja;Jeong, Sang-Seom;Jeon, Young-Jin;Lee, Cheol-Ju
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.4
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    • pp.5-16
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    • 2018
  • In the current study, the engineering behaviour of prebored and precast steel pipe piles was examined from a series of full-scale field measurements by conducting static pile load tests, dynamic pile load tests (EOID and restrike tests) and Class-A and Class-C1 type numerical analysis. The study includes the pile load - settlement relations, allowable pile capacity and shear stress transfer mechanism. Compared to the allowable pile capacity obtained from the static pile load tests, the dynamic pile load tests and the numerical simulation showed surprisingly large variations. Overall among these the restrike tests displayed the best results, however the reliability of the predictions from the numerical analysis was lower than those estimated from the dynamic pile load tests. The allowable pile capacity obtained from the EOID tests and the restrike tests indicated 20.0%-181.0% (avg: 69.3%) and 48.2%-181.1% (avg: 92.1%) of the corresponding measured values from the static pile loading tests, respectively. Furthermore, the computed results from the Class-A type analysis showed the largest scatters (37.1%-210.5%, avg: 121.2%). In the EOID tests, a majority of the external load were carried by the end bearing pile capacity, however, similar skin friction and end bearing capacity in magnitude were mobilised in the restrike tests. The measured end bearing pile capacity from the restrike tests were smaller than was measured from the EOID tests. The present study has revealed that if the impact energy is not sufficient in a restrike test, the end bearing pile capacity most likely will be underestimated. The shear stresses computed from the numerical analysis deviated substantially from the measured pile force distributions. It can be concluded that the engineering behaviour of the pile is heavily affected if a slime layer exists near the pile tip, and that the smaller the stiffness of the slime and the thicker the slime, the greater the settlement of the pile.

A Verification on the Effectiveness of Middle Managers' Emotional Leadership in Food Service Management Companies (위탁급식업체 중간관리자의 감성리더십 효과성 검증)

  • Kim, Hyun-Ah;Jung, Hyun-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.4
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    • pp.488-498
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    • 2007
  • The purposes of this study were to: a) provide evidences concerning the effects of emotional leadership b) examine the impacts of emotional leadership on employee-related variables, 'job satisfaction', 'organizational commitment', 'organizational performance' and 'turnover intention', and c) identify a conceptual framework underlying emotional leadership. A survey was conducted from August 23 to November 3, 2005 to collect data from mid-level managers in food service company headquarters (N=219). Statistical analyses were completed using SPSS Win (12.0) for descriptive, reliability, factor and correlation analyses and AMOS (5.0) for confirmatory factor analysis and structural equation modeling. The main results of this study were as follows. First, the managers gave the highest point to their leaders in the emotional leadership competence 'organizational awareness : reading the currents, decision networks, and politics at the organizational level' and gave the lowest point in the emotional leadership competence 'influence: wielding effective tactics for persuasion'. Second, the means of job satisfaction was above the midpoint (3 points). Employees' job satisfaction with 'coworkers' was relatively high. However, the extents of satisfaction with 'payroll' 'promotion', and 'work environment' were relatively low. Third, the organizational commitment was above the midpoint (3 points). In the organizational commitment, 'loyalty' factor was higher than 'commitment' factor. Fourth, the means of organizational performance was above the midpoint. The highest organizational performance variable was 'internal efficiency; trying to reduce cost' and the lowest organizational performance variable was 'internal fairness ; equitable treatment and all are treated with respect with no regard to status and grade'. Fifth, most respondents intended on 'thinking of quitting ; towards turnover process'. Sixth, the test of hypothesis using structural equation modeling found that emotional leadership produced p[Isitive effects on job attitude and job performance. Emotional leadership enhanced job satisfaction and organizational commitment, and in turn, employees' attitude positive effects on organizational performance; emotional leadership also had a direct impact on organizational performance

A Comparative Study on Injury Severity, Self esteem, Health Locus of control and Health Promotion Lifestyles between Helmeted and Nonhelmeted Motorcycle Accident Victims (오토바이 사고환자의 안전모 착용여부에 따른 뇌 손상비교와 자아존중감, 건강통제위 성격, 건강증진행위의 비교연구)

  • 최스미
    • Journal of Korean Academy of Nursing
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    • v.23 no.4
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    • pp.585-601
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    • 1993
  • Data on 63 patients who had had motorcycle accidents and who were admitted to four general hospitals in the Chung Chung Nam Do area from July / 1993 to August 1993 were analyzed. The tool used for this study was a structured questionnaire which consisted of ten items on self- esteem, 18 items on health locus of control and 37 items profiling health prometion lifestyle. Injury severity scores were calculated bated based on data from the patients’ medical records. The collected data were analyzed using the SPSS, yielding descriptive statistics, t-test, ANOVA, Pearson’s Product Moment Correlation. The findings of this study are as follows. 1) Of the 63 injured motorcyclists, 35(55.6%) were helmeted and 28(44.4%) were nonhelmeted, and the nonhelmeted motorcyclists were predominantly young and male. The demographic variables for the helmeted and nonhelmeted groups were heterogeneous for age and occupation. 2) The results of the comparison between the two groups showed a statistically significant difference in the injury severity score(t=-4.70, p=0.000). The helmeted group had lower scores on injury severity score (9.00±3.93) than the nonhelmeted group(14.32土5.05). More than 60% of the nonhelmeted motorcyclists had brain injuries compared to only a third of the helmeted cyclists. 3) There .was a statistically significant difference between the two groups on self esteem(t=4.5, 000). The helmeted group had a higher mean score (31.27±2.72) than the nonhelmeted group(27.46±3.80). 4) The means for Internal health locus of control (IHLC), Powerful others health locus of control (PHLC), and Chance health locus of control (CHLC) in the two groups were similar to instrument norms reported in other literature. The mean scores on the IHLC in the two groups were higher than scores on the PHLC or the CHLC. However, there was a significant difference between the mean scores for the two groups on the PHLC (t=2.85, P=0.006). 5) The mean score for the helmeted group on the health promotion lifestyle profile was higher than the mean score for the nonhelmeted group(107.30±11.10, 96.57土 15.54 respectively), and there was a significant difference between the mean scores (t=3.64, p=0.001) . The highest score for helmeted group on the health promotion lifestyle profile was in the health care domain. However, for the nonhelmeted group the highest score was in the exercise domain and the lowest score was in the health care domain. 6) With regard to the relationship between health promotion lifestyle, health locus of control and self esteem in the two groups, the correlation coefficient between health promotion lifestyle and internal health locus of control for the helmeted group was 50(p〈0.01). For the nonhelmeted group, there was no correlation between health promotion lifestyle and internal health locus of control. However, there were significant correlation between health pro-motion lifestyle and external locus of control(r=0. 46, p〈0.01), and self esteem(r=0.495, p〈0.01). 7) Among the demographic variables, age and education had an impact on individual’s self-esteem The modifying factors of age made a contribution to explaining health - promoting lifestyle. In the present study, more than 40% rf the motorcyclists were riding without a helmet. The incidence of brain injury for patients riding without a helmet was nearly twice as high in the nonhelmeted rider as compared to the helmeted rider. The nonhelmeted motorcyclists in this study had lower self-esteem, obtained a higher score on the IHLC, and were not strongly engaged in performing health promotion activities as compared to the helmeted riders. However, some of the nonhelmeted riders who had a strong belief in PHLC were positively associated with engaging in health promotion activities. Based on the results obtained from this study, strategies to promote helmet usage for motorcyclists have to be developed.

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Measuring the Third-Person Effects of Public Opinion Polls: Focusing On Online Polls (여론조사보도에 대한 제3자효과 검증: 온라인 여론조사를 주목하며)

  • Kim, Sung-Tae;Willnat, Las;Weaver, David
    • Korean journal of communication and information
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    • v.32
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    • pp.49-73
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    • 2006
  • During the past decades, public opinion polls have become an ubiquitous tool for probing the complexity of people's beliefs and attitudes on a wide variety of issues. Especially since the late 1970s, the use of polls by news organizations has increased dramatically. Along with the proliferation of traditional polls, in the past few years pollsters and news organizations have come to recognize the advantages of online polls. Increasingly there has been more effort to take the pulse of the public through the Internet. With the Internet's rapid growth during the past years, advocates of online polling often emphasize the relative advantages over traditional polls. Researchers from Harris Black International Ltd., for example, argue that "Internet polling is less expensive and faster and offers higher response rates than telephone surveys." Moreover, since many of the newer online polls draw respondents from large databases of registered Internet users, results of online polls have become more balanced. A series of Harris Black online polls conducted during the 1998 gubernatorial and senatorial elections, for example, has accurately projected the winners in 21 of the 22 races it tracked. Many researchers, however, severely criticize online polls for not being representative of the larger population. Despite the often enormous number of participants, Internet users who participate in online polls tend to be younger, better educated and more affluent than the general population. As Traugott pointed out, the people polled in Internet surveys are a "self selected" group, and thus "have volunteered to be part of the test sample, which could mean they are more comfortable with technology, more informed about news and events ... than Americans who aren't online." The fact that users of online polls are self selected and demographically very different from Americans who have no access to the Internet is likely to influence the estimates of what the majority of people think about social or political issues. One of the goals of this study is therefore to analyze whether people perceive traditional and online public opinion polls differently. While most people might not differentiate sufficiently between traditional random sample polls and non representative online polls, some audiences might perceive online polls as more useful and representative. Since most online polls allow some form of direct participation, mostly in the form of an instant vote by mouse click, and often present their findings based on huge numbers of respondents, consumers of these polls might perceive them as more accurate, representative or reliable than traditional random sample polls. If that is true, perceptions of public opinion in society could be significantly distorted for those who rely on or participate in online polls. In addition to investigating how people perceive random sample and online polls, this study focuses on the perceived impact of public opinion polls. Similar to these past studies, which focused on how public opinion polls can influence the perception of mass opinion, this study will analyze how people perceive the effects of polls on themselves and other people. This interest springs from prior studies of the "third person effect," which have found that people often tend to perceive that persuasive communications exert a stronger influence on others than on themselves. While most studies concerned with the political effects of public opinion polls show that exit polls and early reporting of election returns have only weak or no effects on the outcome of election campaigns, some empirical findings suggest that exposure to polls can move people's opinions both toward and away from perceived majority opinion. Thus, if people indeed believe that polls influence others more than themselves, perceptions of majority opinion could be significantly altered because people might anticipate that others will react more strongly to poll results.

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