scholarly journals The fake food buffet – a new method in nutrition behaviour research

2011 ◽  
Vol 107 (10) ◽  
pp. 1553-1560 ◽  
Author(s):  
T. Bucher ◽  
K. van der Horst ◽  
M. Siegrist
Keyword(s):  
Experimental Method ◽  
Experimental Research ◽  
External Validity ◽  
Food Choice ◽  
Energy Content ◽  
Correlation Coefficients ◽  
The Other ◽  
Experimental Assessment ◽  
Food Items ◽  
Portion Sizes

Experimental research in behavioural nutrition is often limited by practical applicability. In the present study, we assess the reproducibility and validity of a new experimental method using food replicas. A total of fifty-seven people were invited on two separate occasions with an interval of 2 weeks to serve themselves a meal from a fake food buffet (FFB) containing replica carrots, beans, pasta and chicken. The external validity of the FFB was assessed in a second study by comparing meals served from replica foods (beans, pasta, chicken) with meals served from a corresponding real food buffet (RFB). For the second study, forty-eight participants were invited on two separate occasions; first to serve themselves a meal from the FFB or an RFB and 2 weeks later from the other buffet. The amounts of food items served and (theoretical) energy content were compared. Correlation coefficients between the amounts of fake foods served were 0·77 (95 % CI 0·68, 0·86) for chicken, 0·79 (95 % CI 0·68, 0·87) for carrots, 0·81 (95 % CI 0·69, 0·89) for beans and 0·89 (95 % CI 0·82, 0·93) for pasta. For the FFB meal and the RFB meal, the correlations ranged between 0·76 (95 % CI 0·73, 0·91) for chicken and 0·87 (95 % CI 0·77, 0·92) for beans. The theoretical energy of the fake meal was 132 kJ (32 kcal) lower compared to the energy of the real meal. Results suggest that the FFB can be a valuable tool for the experimental assessment of relative effects of environmental influences on portion sizes and food choice under well-controlled conditions.

Improving the External Validity of Conjoint Analysis: The Essential Role of Profile Distribution

2021 ◽  
pp. 1-27 ◽  
Author(s):  
Brandon de la Cuesta ◽  
Naoki Egami ◽  
Kosuke Imai
Keyword(s):  
Conjoint Analysis ◽  
Real World ◽  
External Validity ◽  
Causal Effect ◽  
The Other ◽  
Estimation Methods ◽  
Social Scientists ◽  
Actual Distribution ◽  
Open Source Software Package ◽  
Profile Distribution

Abstract Conjoint analysis has become popular among social scientists for measuring multidimensional preferences. When analyzing such experiments, researchers often focus on the average marginal component effect (AMCE), which represents the causal effect of a single profile attribute while averaging over the remaining attributes. What has been overlooked, however, is the fact that the AMCE critically relies upon the distribution of the other attributes used for the averaging. Although most experiments employ the uniform distribution, which equally weights each profile, both the actual distribution of profiles in the real world and the distribution of theoretical interest are often far from uniform. This mismatch can severely compromise the external validity of conjoint analysis. We empirically demonstrate that estimates of the AMCE can be substantially different when averaging over the target profile distribution instead of uniform. We propose new experimental designs and estimation methods that incorporate substantive knowledge about the profile distribution. We illustrate our methodology through two empirical applications, one using a real-world distribution and the other based on a counterfactual distribution motivated by a theoretical consideration. The proposed methodology is implemented through an open-source software package.

scholarly journals Healthy decisions in the cued-attribute food choice paradigm have high test-retest reliability

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zahra Barakchian ◽  
Anjali Raja Beharelle ◽  
Todd A. Hare
Keyword(s):  
Food Choice ◽  
Food Choices ◽  
Retest Reliability ◽  
Individual Level ◽  
Food Items ◽  
Intervention Efficacy ◽  
The Individual ◽  
Test Retest Reliability ◽  
Decision Mechanisms ◽  
High Test

AbstractFood choice paradigms are commonly used to study decision mechanisms, individual differences, and intervention efficacy. Here, we measured behavior from twenty-three healthy young adults who completed five repetitions of a cued-attribute food choice paradigm over two weeks. This task includes cues prompting participants to explicitly consider the healthiness of the food items before making a selection, or to choose naturally based on whatever freely comes to mind. We found that the average patterns of food choices following both cue types and ratings about the palatability (i.e. taste) and healthiness of the food items were similar across all five repetitions. At the individual level, the test-retest reliability for choices in both conditions and healthiness ratings was excellent. However, test-retest reliability for taste ratings was only fair, suggesting that estimates about palatability may vary more from day to day for the same individual.

scholarly journals COVID-19: systematic learning across boundaries requires a conceptual agreement

2021 ◽  
pp. 140349482110270
Author(s):  
Knut Ole Sundnes ◽  
Geir Sverre Braut
Keyword(s):  
Public Health ◽  
Knowledge Base ◽  
External Validity ◽  
Evaluation Research ◽  
The Other ◽  
Basic Knowledge ◽  
Early Publication ◽  
Number Of Publications ◽  
Short Time

The COVID-19 epidemic has revealed a shortage of basic knowledge and understanding of pandemics, especially regarding their dynamics and how to contain them. The results are a host of governments’ decrees and instructions, one replacing the other, often within the same week. It has further, in a truly short time, resulted in an overwhelming number of publications, many of them prioritising early publication over quality. This commentary addresses the concept of structured research related to disasters and how the use of endorsed guidelines will facilitate well-designed evaluation research with improved rigour and external validity, even if applied retrospectively. The outcome should be a solidified knowledge base. Further, the important role of public health efforts is to be highlighted, as their role has proved crucial during the COVID-19 pandemic.

SERUM GONADOTROPHINS, TESTOSTERONE AND SPERMATOGENESIS IN SUBFERTILE MEN

1977 ◽  
Vol 86 (3) ◽  
pp. 651-658 ◽  
Author(s):  
J. H. Aafjes ◽  
J. C. M. van der Vijver ◽  
R. Docter ◽  
P. E. Schenck
Keyword(s):  
Partial Correlation ◽  
Sperm Count ◽  
Correlation Coefficients ◽  
Serum Levels ◽  
Significant Negative Correlation ◽  
The Other ◽  
Sperm Production ◽  
Positive Correlation ◽  
Natural Logarithm ◽  
Biopsy Score

ABSTRACT In 210 subfertile men there existed a significant positive correlation between serum FSH and LH (0.41). No correlation was observed between the gonadotrophin levels and testosterone. In contrast to this FSH as well as LH were negatively correlated with the natural logarithm (In) of the sperm count/ml ejaculate (−0.44 and −0.18, respectively). When the positive correlation which existed between FSH and LH was used to calculate partial correlation coefficients, the coefficient between FSH and ln sperm count did hardly change (−0.41) the coefficient between LH and ln sperm count on the other hand became insignificant (−0.05). This suggests that spermatogenesis influences FSH serum levels in subfertile men by a decreased suppression when sperm production is diminished. Testicular biopsies taken from 97 of these patients were used to determine biopsy scores. These scores showed a significant negative correlation with FSH (−0.34) and a positive one with ln sperm count/ml ejaculate (0.45). Interestingly the biopsy score of 16 patients who fertilized their wives, was found to be higher compared with the score of the other patients who did not fertilize. The number of sperm/ml ejaculate and the FSH values of these 2 groups of biopsied patients were, however, not significantly different. This leads to the conclusion that the biopsy score is a better parameter for the evaluation of oligospermic men than either sperm count or FSH serum values.

Automatic Detection of Periodic Limb Movements in Sleep (PLMS), And Analysis of Their Relationship to Heart Rate Signals

2021 ◽  
Author(s):  
Sharadha Kolappan
Keyword(s):  
Heart Rate ◽  
Correlation Coefficients ◽  
Limb Movement ◽  
The Other ◽  
Screening Tools ◽  
Periodic Limb Movements ◽  
Periodic Limb Movement ◽  
Related Disorder ◽  
The Relationship ◽  
Core Features

Periodic Limb Movement in Sleep (PLMS) are a sleep-related disorder of the limbs that increasingly more research has begun to associate with severe Cardiovascular Diseases (CVD). With that said, Polysomnography (PSG), followed by manual scoring, is the conventional approach being used to monitor the disorder. However, patient inconvenience, and the high costs associated with PSG, has probed the need for alternative screening tools to be developed. Moreover, due to the cumbersome and time-consuming nature of manually scoring for PLMS, more studies have begun to look into automated means of detecting PLMS. Hence, while one of the goals of the current thesis was to use the latest clinical specifications to develop an automated Periodic Limb Movement (PLM) detector, the other goal was to look into alternative signals to monitor PLMS. With that said, in the current thesis, an automated PLM detector was developed and tested on two datasets. In fact, the results were promising in that, correlation coefficients of 0.78 and 0.8, and absolute differences not greater than 9 and 6 (not including the extreme outliers) respectively, were found when comparing the clinical PLM scores with that of the automated algorithm’s PLM scores. Moreover, not only did the automated PLM detector compute PLM scores, it also provided us with PLM segmentation information, i.e., localization of PLM with respect to time. On the other hand, with regards to finding alternative signals to monitor PLMS, the etiology of PLMS was used in order to validate the use of relatively easily acquirable signals, such as Heart Rate (HR) signals, to monitor the condition. Moreover, core features were extracted from the HR signals and the PLM segmentation information from the developed PLM detector was used in order to perform individuaized classification between PLM and non-PLM segments (per subject). Although the results were promising in that, the percent of correctly identifying a given segment as PLM or non-PLM, using the HR features, across most of the subjects, i.e., especially those with PLM Index ≥ 15, were around and well above the 70% range, due to the possibility of other factors interfering with HR during sleep, a more immediate application of the observed PLMS vs HR distinction was, to be able to monitor the autonomic health of an individual, given their PLM information. Specifically, the latter was anticipated to be useful for studies looking into the relationship between PLMS and HR, and thus CVD, or more significantly, those looking into preventing CVD by treating PLM.

Experiment

2016 ◽  
Author(s):  
Uljana Feest ◽  
Friedrich Steinle
Keyword(s):  
Social Sciences ◽  
Causal Inference ◽  
Experimental Research ◽  
The Other ◽  
Dynamic Processes ◽  
Philosophical Work ◽  
Entity Realism ◽  
Experimental Systems ◽  
The World

The authors provide an overview of philosophical discussions about the roles of experiment in science. First, they cover two approaches that took shape under the heading of “new experimentalism” in the 1980s and 1990s. One approach was primarily concerned with questions about entity realism, robustness, and epistemological strategies. The other has focused on exploratory experiments and the dynamic processes of experimental research as such, highlighting its iterative nature and drawing out the ways in which such research is grounded in experimental systems, concepts and operational definitions. Second, the authors look at more recent philosophical work on the epistemology of causal inference, in particular highlighting discussions in the philosophy of the behavioral and social sciences, concerning the extrapolation from laboratory contexts to the world.

IV.—The Mammoth in Siberia

1880 ◽  
Vol 7 (9) ◽  
pp. 408-414
Author(s):  
Henry H. Howorth
Keyword(s):  
Experimental Method ◽  
The Other ◽  
Boundary Line ◽  
Modern Development ◽  
The Subject ◽  
The One ◽  
Neutral Ground

The overlapping of the sciences is made the subject of much rhetorical writing now-a-days, and its appreciation is one of the most prominent signs of the modern development of the doctrine of Continuity which has been so fruitful in the Philosophy of Discovery. The boundary-line which once separated the geologist and ethnologist has in consequence of this development entirely disappeared, and every one now admits as a postulate that between the two sciences there is a stretch of neutral ground belonging to neither exclusively, and where the students of each must of necessity reap if their harvest is to be complete. Not only so, but it is beginning to be seen that the methods and the directions of the arguments in each science being more or less different—the one partaking much more of the historical, and the other of the experimental method—that it is well that where they overlap the results of each should be closely compared, and thus not only secure a double modicum of certitude, but also suggest fresh veins of untried material where we may put in our mattock with renewed hope of solving some apparently hopeless problems.

Age and food hardness affect food handling by insectivorous bats

2007 ◽  
Vol 85 (9) ◽  
pp. 985-993 ◽  
Author(s):  
E.E. Fraser ◽  
M.B. Fenton
Keyword(s):  
Optimal Foraging ◽  
Feeding Behaviour ◽  
Eating Behaviour ◽  
Myotis Lucifugus ◽  
The Other ◽  
Food Handling ◽  
Insectivorous Bats ◽  
Male And Female ◽  
Food Items ◽  
And Gender

Eating behaviour can vary with age, experience, and gender, as well as food hardness. This variation can contribute to intraspecific dietary differences and may result in variable definitions of optimal foraging and decreased intraspecific competition. We quantified feeding behaviour of insectivorous bats eating hard and soft mealworm-based food items based on the bats’ ability to consume and manipulate food items, consumption time, chew frequency, and total chews to consume. Adult Myotis lucifugus (LeConte, 1831) were more successful at both consuming and manipulating mealworms and consumed mealworms more quickly, with greater chew frequency and in fewer chews, than did subadults. Adults chewed mealworm viscera more frequently than did subadults but showed no differences in the other variables. Adult Eptesicus fuscus (Beauvois, 1796) consumed mealworms more quickly and with fewer chews than did subadults but showed no differences in the other variables. There were no differences between adult and subadult E. fuscus when consuming mealworm viscera. Male and female M. lucifugus did not differ significantly when eating either mealworms or mealworm viscera. There was no change in subadult consumption time of mealworms over the summer. Age-based differences in eating abilities may play a role in defining optimal foraging and dietary composition in insectivorous bats.

scholarly journals Validation of a food-frequency questionnaire for cohort studies in rural Japan

2003 ◽  
Vol 6 (2) ◽  
pp. 147-157 ◽  
Author(s):  
Keiko Ogawa ◽  
Yoshitaka Tsubono ◽  
Yoshikazu Nishino ◽  
Yoko Watanabe ◽  
Takayoshi Ohkubo ◽  
...  
Keyword(s):  
Cohort Studies ◽  
Total Energy ◽  
Food Frequency Questionnaire ◽  
Correlation Coefficients ◽  
Food Groups ◽  
Daily Consumption ◽  
Cross Sectional ◽  
Food Frequency ◽  
Food Items ◽  
Miyagi Prefecture

AbstractObjectives:To examine the validity and reproducibility of a self-administered food-frequency questionnaire (FFQ) used for two cohort studies in Japan.Design:Cross-sectional study.Setting:Two rural towns in the Miyagi Prefecture, in north-eastern Japan.Subjects:Fifty-five men and 58 women.Results:A 40-item FFQ was administered twice, 1 year apart. In the mean time, four 3-day diet records (DRs) were collected in four seasons within the year. We calculated daily consumption of total energy and 15 nutrients, 40 food items and nine food groups from the FFQs and the DRs. We computed Spearman correlation coefficients between the FFQs and the DRs. With adjustment for age, total energy and deattenuation for measurement error with the DRs, the correlation coefficients for nutrient intakes ranged from 0.25 to 0.58 in men and from 0.30 to 0.69 in women, with median of 0.43 and 0.43, respectively. Median (range) of the correlation coefficients was 0.35 (−0.30 to 0.72) in men and 0.34 (−0.06 to 0.75) in women for food items and 0.60 (−0.10 to 0.76) and 0.51 (0.28–0.70) for food groups, respectively. Median (range) of the correlation coefficients for the two FFQs administered 1 year apart was 0.49 (0.31–0.71) in men and 0.50 (0.40–0.64) in women for nutrients, 0.43 (0.14–0.76) and 0.45 (0.06–0.74) respectively for food items, and 0.50 (0.30–0.70) and 0.57 (0.39–0.66) respectively for food groups. Relatively higher agreement percentages for intakes of nutrients and food groups with high validity were obtained together with lower complete disagreement percentages.Conclusions:The FFQ has a high reproducibility and a reasonably good validity, and is useful in assessing the usual intakes of nutrients, foods and food groups among a rural Japanese population.

scholarly journals Measurement for accentedness, pause frequency/duration and nuclear stress placement in the EFL classroom

2017 ◽  
Vol 70 (3) ◽  
pp. 185-200
Author(s):  
Pedro Luis Luchini
Keyword(s):  
Multivariate Analysis ◽  
Experimental Research ◽  
Native Speaker ◽  
The Other ◽  
Speaking Test ◽  
Phonological Form ◽  
Group B ◽  
English Native Speaker ◽  
Teacher Centered ◽  
Stress Placement

This study reports on an experimental research carried out with 50 Spanish-L1 trainees, divided into 2 groups: A & B. Both groups were presented with a traditional-teacher centered approach based on controlled exercises (repetition, imitation), but group B added a communicative component in which students completed a battery of sequenced tasks with a focus on phonological form. Both groups recorded a speaking test before & after instruction which was used to measure and compare degrees of accentedness, frequency & duration of pauses and nuclear stress placement. Ten English-native-speaker-raters judged the recordings to determine the speakers’ degree of perceived accentedness. Two specialists, using inter-marker reliability, segmented the transcriptions of recordings and identified nuclear stress placement. Another two specialists identified empty pauses. Multivariate analysis was used to measure results. Overall, group B (learners exposed to the communicative component) obtained better results in all 3 parameters than the other group. Finally, some pedagogical implications for the teaching of L2 pronunciation in ELT contexts will be discussed. 

Sign in / Sign up

Export Citation Format

Share Document