Livestock exclusion reduces the temporal stability of grassland productivity regardless of eutrophication

Abstract Eutrophication is a widespread environmental change that usually reduces the stabilizing effect of plant diversity on productivity in local communities. Whether this effect is scale dependent remains to be elucidated. Here, we determine the relationship between plant diversity and temporal stability of productivity for 243 plant communities from 42 grasslands across the globe and quantify the effect of chronic fertilization on these relationships. Unfertilized local communities with more plant species exhibit greater asynchronous dynamics among species in response to natural environmental fluctuations, resulting in greater local stability (alpha stability). Moreover, neighborhood communities that have greater spatial variation in plant species composition within sites (higher beta diversity) have greater spatial asynchrony of productivity among communities, resulting in greater stability at the larger scale (gamma stability). Importantly, fertilization consistently weakens the contribution of plant diversity to both of these stabilizing mechanisms, thus diminishing the positive effect of biodiversity on stability at differing spatial scales. Our findings suggest that preserving grassland functional stability requires conservation of plant diversity within and among ecological communities.

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Plant functional traits improve diversity-based predictions of temporal stability of grassland productivity

Oikos ◽

10.1111/j.1600-0706.2013.00338.x ◽

2013 ◽

Vol 122 (9) ◽

pp. 1275-1282 ◽

Cited By ~ 51

Author(s):

H. Wayne Polley ◽

Forest I. Isbell ◽

Brian J. Wilsey

Keyword(s):

Functional Traits ◽

Temporal Stability ◽

Plant Functional Traits ◽

Grassland Productivity

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Instrumental and Ideological Union Commitment: Longitudinal Assessment of Construct Validity

European Journal of Psychological Assessment ◽

10.1027//1015-5759.17.2.98 ◽

2001 ◽

Vol 17 (2) ◽

pp. 98-111 ◽

Cited By ~ 1

Author(s):

Anders Sjöberg ◽

Magnus Sverke

Keyword(s):

Construct Validity ◽

Temporal Stability ◽

Strong Support ◽

Internal Consistency Reliability ◽

Measurement Model ◽

Two Dimensions ◽

Model Parameters ◽

Longitudinal Assessment ◽

Union Commitment ◽

Union Participation

Summary: Previous research has identified instrumentality and ideology as important aspects of member attachment to labor unions. The present study evaluated the construct validity of a scale designed to reflect the two dimensions of instrumental and ideological union commitment using a sample of 1170 Swedish blue-collar union members. Longitudinal data were used to test seven propositions referring to the dimensionality, internal consistency reliability, and temporal stability of the scale as well as postulated group differences in union participation to which the scale should be sensitive. Support for the hypothesized factor structure of the scale and for adequate reliabilities of the dimensions was obtained and was also replicated 18 months later. Tests for equality of measurement model parameters and test-retest correlations indicated support for the temporal stability of the scale. In addition, the results were consistent with most of the predicted differences between groups characterized by different patterns of change/stability in union participation status. The study provides strong support for the construct validity of the scale and indicates that it can be used in future theory testing on instrumental and ideological union commitment.

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Internal Structure of the Spanish Adaptation of the Eating Disorder Inventory-3

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000087 ◽

2012 ◽

Vol 28 (1) ◽

pp. 25-31 ◽

Cited By ~ 7

Author(s):

Paula Elosua ◽

Alicia López-Jáuregui

Keyword(s):

Eating Disorders ◽

Eating Disorder ◽

Internal Structure ◽

Internal Consistency ◽

Clinical Sample ◽

Temporal Stability ◽

Second Order ◽

Order Structure ◽

Eating Disorder Inventory ◽

High Internal Consistency

In this study the Eating Disorder Inventory-3 was adapted to Spanish and analyzed the internal psychometric properties of the test in a clinical sample of females with eating disorders. The results showed a high internal consistency of the scores as well as high temporal stability. The factor structure of the scale composites was analyzed using confirmatory factor analysis. The results supported the existence of a second-order structure beyond the psychological composites. The second-order factor showed high correlation with the factor related to eating disorders. Overall, the Spanish version of the EDI-3 showed good psychometric qualities in terms of internal consistency, temporal stability and internal structure.

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I Like Myself, I Really Do (at Least Right Now)

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000501 ◽

2020 ◽

Vol 36 (1) ◽

pp. 196-206 ◽

Cited By ~ 1

Author(s):

Almut Rudolph ◽

Michela Schröder-Abé ◽

Astrid Schütz

Keyword(s):

Construct Validity ◽

Performance Feedback ◽

Repeated Measures ◽

Temporal Stability ◽

Social Feedback ◽

Student Sample ◽

Empirically Supported ◽

Good Internal Consistency ◽

And Performance ◽

Induced Changes

Abstract. In five studies, we evaluated the psychometric properties of a revised German version of the State Self-Esteem Scale (SSES; Heatherton & Polivy, 1991 ). In Study 1, the results of a confirmatory factor analysis on the original scale revealed poor model fit and poor construct validity in a student sample that resembled those in the literature; thus, a revised 15-item version was developed (i.e., the SSES-R) and thoroughly validated. Study 2 showed a valid three-factor structure (Performance, Social, and Appearance) and good internal consistency of the SSES-R. Correlations between subscales of trait and state SE empirically supported the scale’s construct validity. Temporal stability and intrapersonal sensitivity of the scale to naturally occurring events were investigated in Study 3. Intrapersonal sensitivity of the scale to experimentally induced changes in state SE was uncovered in Study 4 via social feedback (acceptance vs. rejection) and performance feedback (positive vs. negative). In Study 5, the scale’s interpersonal sensitivity was confirmed by comparing depressed and healthy individuals. Finally, the usefulness of the SSES-R was demonstrated by assessing SE instability as calculated from repeated measures of state SE.

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Implications of Person Fluctuation for the Stability and Validity of Test Scores

Methodology ◽

10.1027/1614-2241.2.4.142 ◽

2006 ◽

Vol 2 (4) ◽

pp. 142-148 ◽

Cited By ~ 1

Author(s):

Pere J. Ferrando

Keyword(s):

Item Response ◽

Test Scores ◽

Temporal Stability ◽

Person Fit ◽

Item Parameters ◽

Individual Trait ◽

The Stability ◽

The Individual ◽

Different Levels ◽

Fluctuation Model

In the IRT person-fluctuation model, the individual trait levels fluctuate within a single test administration whereas the items have fixed locations. This article studies the relations between the person and item parameters of this model and two central properties of item and test scores: temporal stability and external validity. For temporal stability, formulas are derived for predicting and interpreting item response changes in a test-retest situation on the basis of the individual fluctuations. As for validity, formulas are derived for obtaining disattenuated estimates and for predicting changes in validity in groups with different levels of fluctuation. These latter formulas are related to previous research in the person-fit domain. The results obtained and the relations discussed are illustrated with an empirical example.

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