Second Hypothesis (second + hypothesis)

Distribution by Scientific Domains


Selected Abstracts


The impact of operational characteristics on firms' EMS decisions: strategic adoption of ISO 14001 certifications

CORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 4 2010
Takuya Takahashi
Abstract Firms choose to seek environmental management system (EMS) certifications such as ISO 14001 for a variety of reasons. In this paper we put forward a hypothesis that firms seek ISO 14001 certifications for their establishments when their operations involve low degrees of complexity. Another hypothesis we consider is that firms facing more uncertainty in their operations (and hence more risk) seek ISO 14001 certifications. These hypotheses have not been yet addressed in the literature and are of particular interest to business managers and policymakers. We empirically test these hypotheses using probit and duration models using matched establishment,firm,industry data for large Japanese manufacturers. Our findings support the first as well as the second hypotheses. This suggests that firms tend to certify more routine and less complex operations first, and that firms use ISO 14001 certifications as an insurance scheme. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment. [source]


A conceptual model for the longitudinal distribution of wood in mountain streams

EARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2009
Ellen Wohl
Abstract Wood load, channel parameters and valley parameters were surveyed in 50 contiguous stream segments each 25 m in length along 12 streams in the Colorado Front Range. Length and diameter of each piece of wood were measured, and the orientation of each piece was tallied as a ramp, buried, bridge or unattached. These data were then used to evaluate longitudinal patterns of wood distribution in forested headwater streams of the Colorado Front Range, and potential channel-, valley- and watershed-scale controls on these patterns. We hypothesized that (i) wood load decreases downstream, (ii) wood is non-randomly distributed at channel lengths of tens to hundreds of meters as a result of the presence of wood jams and (iii) the proportion of wood clustered into jams increases with drainage area as a result of downstream increases in relative capacity of a stream to transport wood introduced from the adjacent riparian zone and valley bottom. Results indicate a progressive downstream decrease in wood load within channels, and correlations between wood load and drainage area, elevation, channel width, bed gradient and total stream power. Results support the first and second hypotheses, but are inconclusive with respect to the third hypothesis. Wood is non-randomly distributed at lengths of tens to hundreds of meters, but the proportion of pieces in jams reaches a maximum at intermediate downstream distances within the study area. We use these results to propose a conceptual model illustrating downstream trends in wood within streams of the Colorado Front Range. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Day,night changes in the spatial distribution and habitat preferences of freshwater shrimps, Gammarus pulex, in a stony stream

FRESHWATER BIOLOGY, Issue 4 2005
J. M. ELLIOTT
Summary 1. As many invertebrates are nocturnal, their spatial distribution and habitat preferences may change from day to night. Both aspects are examined for Gammarus pulex by testing the hypotheses: (i) a power function was a suitable model for the spatial distribution of the shrimps in both day and night; (ii) diurnal and nocturnal spatial distributions were significantly different; (iii) diurnal and nocturnal habitat preferences were significantly different. Five different life-stages were treated separately. To ensure that the conclusions were consistent, large samples were taken near midday and midnight in April, June and November over 4 years at two sites about 3 km apart in a stony stream: downstream (n = 30) and upstream (n = 50). 2. The first and second hypotheses were supported at both sites. A power function, relating spatial variance (s2) to mean (m), was an excellent fit in all analyses (P < 0.001, r2 > 0.91), i.e. the spatial variance was density-dependent. All five life-stages were aggregated in the day. At night, the degree of aggregation increased for juveniles at higher densities but decreased for juveniles at lower densities, increased for immature females and males, but decreased slightly for mature females and especially mature males, the latter being close to a random distribution. There were no significant differences between sites, in spite of the lower numbers at the downstream site. 3. The third hypothesis was tested at only the upstream site and supported by comparisons between shrimp densities and 13 physical variables (distance from bank, water depth, water velocity, ten particle size-classes), and three non-physical variables (dry weights of bryophytes, leaf material, organic detritus). During the day, densities were strongly related to particle sizes with the following preferences: 0.5,8 mm for juveniles, 8,256 mm for the other life-stages with a weaker relationship for males. There were no significant positive relationships with the other variables, apart from bryophytes for immature shrimps and adults. At night, densities were unrelated to particle size; juveniles and immature shrimps preferred low water velocities near the banks, often where leaf material and organic detritus accumulated, females often preferred medium water velocities slightly away from the banks, and males showed no habitat preferences. 4. Day samples do not provide a complete picture of habitat preferences and probably identify refuge habitats. Day,night changes in spatial distribution and habitat preferences are an essential part of the behavioural dynamics of the shrimps and should be investigated in other species. [source]


How female reed buntings benefit from extra-pair mating behaviour: testing hypotheses through patterns of paternity in sequential broods

MOLECULAR ECOLOGY, Issue 9 2006
KAREN M. BOUWMAN
Abstract Extra-pair paternity is an important aspect of reproductive strategies in many species of birds. Given that in most species females control whether fertilization occurs, they are expected to benefit in some way from the extra-pair matings. In this study we use patterns of extra-pair paternity (EPP) in broods of individual reed buntings (Emberiza schoeniclus), both within and between seasons, to test four hypothesized female benefits: (1) assessing potential future partners and seeking (2) genetic diversity (3) good genes, or (4) compatible genes. Reed buntings are socially monogamous, multibrooded passerines with extremely high levels of extra-pair paternity. We studied a population of reed buntings in the Netherlands in 2002 and 2003; 51% of offspring in 74% of nests were extra-pair. We showed that patterns of EPP did not support the first and second hypotheses, since females did not form a pair with previous extra-pair partners, EPP was not evenly distributed among broods and more broods than expected were sired by a single male. Furthermore, there was no relation between a male's within- and extra-pair fertilization success, no consistency in EPP between breeding attempts, no effect of parental relatedness on EPP and several cases of reciprocal paternity. These patterns do not support the good genes hypothesis and are most consistent with the genetic compatibility hypothesis. However, our previous finding that older males are more successful in gaining EPP, suggests some effect of good genes. These hypotheses need not be mutually exclusive, as females may select compatible males above a certain quality threshold (e.g. old males). [source]


United we win, divided we fail?

EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2008
Effects of cognitive merger representations, performance feedback on merging groups
Research has shown that cognitive representations of mergers influence intergroup evaluations. This paper extends this research by studying how cognitive representations of mergers (one group, dual identity, and two groups) interact with performance feedback (success and failure) to affect intergroup evaluations. Two competing hypotheses were tested, which made different predictions in case of superordinate group salience combined with subgroup salience after merger failure: The subgroup-salience-hypothesis predicts that subgroup salience during a merger generally results in pre-merger ingroup bias toward the pre-merger outgroup (i.e., two groups and dual identity). The superordinate- salience-hypothesis predicts that subgroup salience only results in pre-merger ingroup bias if superordinate group salience is low (i.e., two groups). Both hypotheses predict low levels of ingroup bias after merger success. Study 1 confirmed the second hypothesis using a 3 (merger representation: one group, dual identity, and two groups),×,2 (merger feedback: failure and success) design with interacting groups. Study 2 replicated the results in an adapted minimal group paradigm. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Recruitment variability of resident brown trout in peripheral populations from southern Europe

FRESHWATER BIOLOGY, Issue 12 2008
GRACIELA G. NICOLA
Summary 1. Population regulation was studied for seven consecutive years (1992,98) in five rivers at the periphery of the distribution of Salmo trutta, where the fish were living under environmental constraints quite different from those of the main distribution area. 2. Recruitment is naturally highly variable and the populations had been earlier classified as overexploited. Thus we expected that densities of young trout in most populations would be too low for density-dependent mortality to operate. We tested this by fitting the abundance of recruits to egg densities over seven consecutive years (stock,recruitment relationship), and used the results to judge whether exploitation should be restricted in the interests of conserving the populations. 3. The density of 0+ trout in early September, as well as the initial density of eggs and parents, varied greatly among localities and years. The data for all populations fitted the Ricker stock,recruitment model. The proportion of variance explained by the population curves varied between 32% and 51%. However, in most cases the observations were in the density-independent part of the stock,recruitment curve, where densities of the recruits increased proportionally with egg densities. 4. Our findings suggest that recruitment densities in most rivers and years were below the carrying capacity of the habitats. Although density-dependent mechanisms seemed to regulate fish abundance in some cases, environmental factors and harvesting appeared generally to preclude populations from reaching densities high enough for negative feedbacks to operate. The findings thus lend support to Haldane's (1956) second hypothesis that changes in population density are primarily due to density-independent factors in unfavourable areas and areas with low density due to exploitation. Exploitation should be reduced to allow natural selection to operate more effectively. [source]


Research to practice: Effectiveness of controlled workplace interventions to reduce musculoskeletal disorders in the manufacturing environment,critical appraisal and meta-analysis

HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 2 2008
Setenay Tuncel
Previous studies on the effectiveness of interventions in reducing musculoskeletal disorders (MSD) in manufacturing facilities had contradictory results, indicating a need for a quality assessment of these studies followed by a quantitative assessment of the overall effectiveness of the interventions. These assessments may also provide suggestions for practical implementations. The first objective of this study is to assess the effectiveness of controlled workplace interventions to reduce the occurrence of MSD in the manufacturing environment by utilizing meta-analysis integrated with the study quality score. The second objective is to translate the research findings into practical guidelines. Two hypotheses were tested pertinent to the first objective: (1) Controlled workplace interventions are effective in reducing the occurrence of MSD in different body regions among manufacturing workers and (2) the study quality scores do not depend on the evaluator. The study quality was assessed for all articles, however, meta effect size (meta-OR) was calculated only for the articles that reported prevalence of low back disorders (LBDs), using the Mantel,Haenszel method. The effect of study quality was included into meta-OR. The chi-square test of independence was employed to test the second hypothesis. Seven articles were identified. Study quality was poor (0.39 out of 2) to moderate (0.97). Insignificant reduction in LBDs prevalence (meta-OR = 0.925; 95% CI: 0.566,1.512) was found. Integration of the study quality did not have a substantial effect on the meta-OR (meta-OR = 0.933; 95% CI: 0.571,1.525). Each evaluator's study quality scores were not independent from the agreed quality scores (p < 0.01). The results suggested that practitioners should consider scientific evidence during design and implementation of an intervention, especially in terms of study duration, confounders, outcome measures, and data analysis. The articles reviewed exhibited the following: (1) the statistical insignificance of the meta-OR; (2) the relatively low methodological quality of studies; and (3) the small number of studies included in the meta-OR. The extent of the generalizability of meta-OR for LBD to other body regions was also in question. Future research should consider the following: (1) the physical and nonphysical work environment should be assessed to determine the workplace-specific needs, and the intervention should be structured around these needs; (2) group comparability, participation rate, subject loss, and randomization of subjects should be taken into account; (3) exposure and outcome measurement methods should be reported, as well as blinding of the observers and subjects, when applicable, to ensure reliability and validity; and (4) data analysis should be conducted adjusting for covariates and confounders, different lengths of follow-up, and level of exposure. © 2008 Wiley Periodicals, Inc. [source]


The glass ceiling in human resources: Exploring the link between women's representation in management and the practices of strategic human resource management and employee involvement

HUMAN RESOURCE MANAGEMENT, Issue 3 2008
Shaun Pichler
Research on sex stereotypes suggests that gender bias is an invisible barrier,the so-called glass ceiling,preventing women from breaking into the highest levels of management in business organizations. Using data from a state-based professional HR organization, we investigated this phenomenon in the field of HR management. Building on the lack of fit model of gender discrimination and previous research, we tested two hypotheses: that women in HR are more likely to be concentrated in lower-level managerial positions in organizations that emphasize employee involvement (because of a related emphasis on stereotypically feminine managerial abilities) and that women in HR also are more likely to be concentrated in lower-level managerial positions in organizations that emphasize strategic human resource management (because of a related emphasis on stereotypically masculine characteristics). Our results support the first but not the second hypothesis. Theoretical and practical implications related to the glass ceiling are discussed. © 2008 Wiley Periodicals, Inc. [source]


Applicant Attraction: The role of recruiter function, work,life balance policies and career salience

INTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 4 2007
Sally A. Carless
This study examined the impact of salient identity, career path and recruiter functional area [internal human resource (HR) personnel vs external recruitment company] on perceptions of organizational attraction with a sample of young, inexperienced job seekers. Two hundred and one participants responded to a questionnaire and rated their attraction to two different job advertisements. The results partially supported the first hypothesis; applicants perceived a job opportunity in an organization that offered either a flexible career path or a dual career path as significantly more attractive than a position in an organization that offered a traditional career path. There was no support for the second hypothesis that identity salience would interact with career path. The results showed that recruiter functional area had no impact on attraction to the organization. It was concluded that flexible HR policies increase applicants' perceptions of organizational attraction during the initial stages of the recruitment process. Practical and research applications are discussed. [source]


A quantitative study of day,night changes in the spatial distribution of insects in a stony stream

JOURNAL OF ANIMAL ECOLOGY, Issue 1 2002
J. M. Elliott
Summary 1As many invertebrates are nocturnal, their spatial distribution may change from day to night. This behavioural aspect of their population dynamics has been ignored, but is now examined for the first time by testing the hypotheses: (i) a power function was a suitable model for the spatial distribution of common species of Ephemeroptera, Plecoptera and Trichoptera in a stony stream; (ii) the spatial distribution varied between species but was similar within species for larvae greater and smaller than half-size; (iii) diurnal and nocturnal spatial distributions were significantly different for each species. To ensure that the conclusions were consistent, large samples (n = 30) were taken near midday and midnight in April, June and November over 4 years. 2Twenty,one species were taken in sufficient numbers for the analyses; seven species were too sparse to be included. The first hypothesis was supported. A power function, relating spatial variance (s2) to mean (m), was an excellent fit in all the analyses (P < 0·001, r2 > 0·95), i.e. the spatial variance was density,dependent. The power b, often used as an ,index of aggregation', varied in the range 0·88,2·50. 3Most analyses supported the second hypothesis. For four species, the difference between the two size groups was just significant (P < 0·05), but was due to inadequate data for three species. Large larvae of the fourth species, the caddis Odontocerum albicorne, were less aggregated than small larvae at night, and were the only group with a b -value less than one. 4The third hypothesis was partially supported. The distribution did not change significantly (P > 0·05) for nine species; five burrowers in gravel, moss or mud, two highly mobile predators, one sedentary, case,building, Trichoptera species, and one net,spinning Trichoptera species. Aggregation was reduced significantly (P < 0·001) at night for four species, all case,building Trichoptera larvae. Aggregation increased significantly (P < 0·001) at night, except at low densities, for the remaining eight species, one being a nocturnal predator and the others being herbivorous species; all occurred frequently in night samples of invertebrate drift. Day,night changes in spatial distribution were therefore an essential part of the behavioural dynamics of 12 of the 21 species, and should be investigated in other species, including terrestrial species. [source]


Hamstrings and iliotibial band forces affect knee kinematics and contact pattern

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2000
S. D. Kwak
Many clinical studies have emphasized the role of the hamstrings and the iliotibial band on knee mechanics, although few biomechanical studies have investigated it. This study therefore examined two hypotheses: (a) with loading of the hamstrings, the tibia translates posteriorly and rotates externally and the tibial contact pattern shifts anteriorly; furthermore, the changes in tibial kinematics alter patellar kinematics and contact; and (b) loading the iliotibial band alters the kinematics and contact pattern of the tibiofemoral joint similarly to loading the hamstrings, and loading the iliotibial band laterally translates the patella and its contact location. Five cadaveric knee specimens were tested with a specially designed knee-joint testing machine in an open-chain configuration. At various flexion angles, the knees were tested always with a quadriceps force but with and without a hamstrings force and with and without an iliotibial band force. The results support the first hypothesis. Hence, the hamstrings may be important anterior and rotational stabilizers of the tibia, a role similar to that of the anterior cruciate ligament. The results also support the second hypothesis, although the iliotibial band force had a smaller effect on the tibia than did the hamstrings force. Both forces also changed patellar kinematics and contact, demonstrating that these structures should also be considered during the clinical management of patellar disorders. [source]


Do spatial effects play a role in the spatial distribution of desert-dwelling Acacia raddiana?

JOURNAL OF VEGETATION SCIENCE, Issue 4 2000
Kerstin Wiegand
Abstract. We investigated the spatial pattern of A. raddiana in the Negev desert of Israel in order to gain insights into the factors and processes driving the dynamics of this species. Using a scale-dependent measure, the ring statistic, we analysed both patterns observed in the field and time series of spatial tree distributions produced by a simulation model. In the field, random spacing was the predominant pattern observed. However seedlings were clumped on small scales. We ran the model under two contrasting scenarios representing hypotheses that explain the clumping of seedlings and the random distribution of trees. One hypothesis is that there is spatial heterogeneity in seed distribution, germination and seedling mortality, but that these heterogeneities are not correlated with each other in space. The second hypothesis assumes a correlation between these heterogeneities leading to areas suitable for establishment. However, the suitability of the sites is temporally variable. Furthermore, the second hypothesis assumes density-dependent tree mortality due to competition. Both hypotheses lead to spatial distributions that are in qualitative agreement with the patterns observed in the field. Therefore, the classical view that a clumped seedling distribution and a random pattern of older trees is due to clumped regeneration and density-dependent mortality may not hold for Acacia trees in the Negev. [source]


Son Preference and Access to Social Insurance: Evidence from China's Rural Pension Program

POPULATION AND DEVELOPMENT REVIEW, Issue 1 2010
Avraham Ebenstein
Many scholars argue that the persistence of son preference in China is driven by greater anticipated old-age support from sons than from daughters and the absence of formal financial mechanisms for families to save for retirement. The introduction of a voluntary old-age pension program in rural China in the 1990s presents the opportunity to examine (1) whether parents with sons are less likely to participate in pension plans and (2) whether providing access to pension plans affects parental sex-selection decisions. Consistent with the first hypothesis, we find that parents with sons are less likely to participate in the pension program and have less financial savings for retirement. Consistent with the second hypothesis, we find that an increase in county-level pension program availability is associated with a slower increase in the sex ratio at birth. [source]


Specificity of regional brain activity in anxiety types during emotion processing

PSYCHOPHYSIOLOGY, Issue 3 2007
Anna S. Engels
Abstract The present study tested the hypothesis that anxious apprehension involves more left- than right-hemisphere activity and that anxious arousal is associated with the opposite pattern. Behavioral and fMRI responses to threat stimuli in an emotional Stroop task were examined in nonpatient groups reporting anxious apprehension, anxious arousal, or neither. Reaction times were longer for negative than for neutral words. As predicted, brain activation distinguished anxious groups in a left inferior frontal region associated with speech production and in a right-hemisphere inferior temporal area. Addressing a second hypothesis about left-frontal involvement in emotion, distinct left frontal regions were associated with anxious apprehension versus processing of positive information. Results support the proposed distinction between the two types of anxiety and resolve an inconsistency about the role of left-frontal activation in emotion and psychopathology. [source]


Personal and cultural differences in responding to criticism in three countries

ASIAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2002
Mary Jiang Bresnahan
The present study investigated whether verbal aggression, argument approach, argument avoidance or assertiveness had any effect on how participants in three countries responded to criticism. Consistent with the first hypothesis, men were significantly more aggressive, assertive, less avoidant, and approached argument more than women. However, men did not respond more assertively to criticism. As predicted in the second hypothesis, US Americans responded more assertively to criticism than did Japanese and Chinese. The third hypothesis predicted that verbal aggression, argument approach, argument avoidance and assertiveness would be associated with a more assertive response to criticism. The data obtained were only partially consistent with the third hypothesis. While only a small number of participants in this study indicated that they would respond to criticism with silence, US Americans used silence to mean anger while for Chinese silence showed personal embarrassment. Very few Japanese selected silence as an option for responding to a neighbor's criticism. The implications of these results are discussed. [source]


Women's perceived experiences of abuse in the health care system: their relationship to childhood abuse

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 12 2004
Katarina Swahnberg
Objectives The aim of this study was to determine whether there was an association between any lifetime experiences of emotional, physical and/or sexual abuse and perceived abuse in the health care system. Furthermore, we wanted to ascertain if adult victims of perceived abuse in the health care system reported exposure to childhood emotional, physical and/or sexual abuse more often than non-victims did. Design A cross sectional questionnaire study. The first hypothesis was tested in the total sample, and the second hypothesis in a case,control analysis. The cases were those women who reported perceived experiences of abuse in the health care system as adults. Exposure was defined as experience of emotional, physical and/or sexual abuse in childhood. Settings Three Swedish gynaecological clinics. Sample A total of 2439 gynaecology patients (response rate 81%). Methods Postal questionnaire. Main outcome measure Associations between experiences of emotional, physical and/or sexual abuse, and perceived abuse in the health care system; all operationalised in The NorVold Abuse Questionnaire (NorAQ). Results A general association was found between lifetime experiences of emotional, physical and/or sexual abuse and perceived abuse in the health care system. Adult victims of abuse in the health care system reported experiences of emotional, physical and/or sexual abuse in childhood more often than non-victims did. These findings also held after adjustment for age and educational level. Conclusions We found associations between experiences of any lifetime abuse and perceived abuse in the health care system. Adult victimisation in the health care system was associated with childhood exposure to emotional, physical and/or sexual abuse. These associations call for attention and need to be further investigated. [source]