Fourier analysis of movement patterns in pigeons

Fourier analysis describes the amount of variation in a time series by partitioning it into sinusoids of different amplitudes and wavelengths and quantifying the extent to which these waves are synchronized. The importance of a given wave is represented by its contribution to the explained variance of the time series. To illustrate its potential application to the study of movement, Fourier analysis was used to quantify the movement patterns of 2 pigeons on a variable-interval (VI) and a variable-time (VT) schedule of reinforcement. For comparison, the movements of 2 pigeons that did not receive reinforcement were similarly analyzed. Characteristic frequencies were higher during VI than during VT, and relatively low during nonreinforcement. We concluded that Fourier analysis can be used to represent movement patterns compactly, study their periodicity, stereotypy, and resonance, and assist in computer simulations and models of movement.     

Show them the money? The role of pay,managerial need support,and justice in a self‐determination theory model of intrinsic work motivation

The link between money and motivation has been a debated topic for decades, especially in work organizations. However, field studies investigating the amount of pay in relation to employee motivation is lacking and there have been calls for empirical studies addressing compensation systems and motivation in the work domain. The purpose of this study was to examine outcomes associated with the amount of pay, and perceived distributive and procedural justice regarding pay in relation to those for perceived managerial need support. Participants were 166 bank employees who also reported on their basic psychological need satisfaction and intrinsic work motivation. SEM‐analyses tested a self‐determination theory (SDT) model, with satisfaction of the competence and autonomy needs as an intervening variable. The primary findings were that amount of pay and employees' perceived distributive justice regarding their pay were unrelated to employees' need satisfaction and intrinsic work motivation, but procedural justice regarding pay did affect these variables. However, managerial need support was the most important factor for promoting need satisfaction and intrinsic work motivation both directly, indirectly, and as a moderator in the model. Hence, the results of the present organizational field study support earlier laboratory experiments within the SDT framework showing that monetary rewards did not enhance intrinsic motivation. This seems to have profound implications for organizations concerned about motivating their employees.     

Phase field modeling of elasto-plastic deformation induced by diffusion controlled growth of a misfitting spherical precipitate

A phase field model accounting for plasticity has been developed using an homogenization scheme for interpolating the constitutive laws within the diffuse interface. The influence of plasticity on the growth of a misfitting spherical precipitate, controlled by solute diffusion has been investigated: plasticity in the matrix slows down the transformation. Moreover, an excellent agreement with the corresponding analytical sharp interface solutions has been achieved.     

Probability of reciprocation in repeated prisoner's dilemma games

Both social cooperation and self‐control require reciprocation. In social cooperation situations a single person's cooperative act, if not reciprocated by others, would be unreinforced both immediately and in the long term. Similarly, a single act of self‐control (refusing a single cigarette, for example), if not followed up by other such acts, would also be unreinforced immediately and in the long term. The present experiments varied probability of reciprocation in a prisoner's dilemma‐like game that could resemble a social cooperation or a self‐control situation. Participants earned points by playing against a computer. The computer offered the participant a choice between 5 or 6 points (‘cooperation’ by the computer) or between 1 or 2 points (‘defection’ by the computer). The participant's choice of the lesser alternative (‘cooperation’) or the greater alternative (‘defection’) on the current trial led, respectively, to cooperation or defection by the computer on the next trial with a probability (probability of reciprocation, PR) which could vary. When PR was greater than 63%, consistent cooperation maximized the participant's earnings. When PR was less than 63%, defection maximized earnings. Three conditions were studied: PR signaled by spinners; PR unsignaled; PR unsignaled with participants believing that they were playing with another person, not the computer. With PR = 100% (‘tit‐for‐tat’) and PR = 50%, the modal participant maximized earnings under all three conditions. With PR = 75%, participants maximized earnings only when PR was signaled. These results indicate that differences between people's tendency to cooperate with other people (social cooperation) and their tendency to cooperate with their own future interests (self‐control) may lie in differences in subjective PR. Copyright © 2001 John Wiley & Sons, Ltd.     

Data discrepancies in the Personal Orientation Inventory Manual

The Personal Orientation Inventory Manual appears to contain a number of errors specifically related to the calculation of the scores for the time ratio and support ratio. Some are of a relatively minor nature, but several are important because they are directly related to the standards whereby individuals are classified as self-actualized, normal, or nonself-actualized. Although part of the discrepancy seems to be due to the number of questions left unanswered by subjects, this does not account for the total difference. At present, it is unclear why the inconsistencies exist.     

Evening and morning EEG differences between young men and women adults

Evening and morning waking EEG (eyes closed) was recorded in 16 women and 13 men aged 18-26 years old. Participants were fitted with a 13-electrode montage (Fp1, Fp2, FZ, F7, F8, C3, C4, T3, T4, P3, P4, O1, and O2) referred to linked ears. For each recording electrode, EEG total spectral amplitude power (microV/Hz, 0.75-19.75 Hz) was compared using 2 (Gender) x 2 (Moments) analyses of variance for repeated measures and LSD post-hoc tests. We found significant simple Gender effects, with women displaying higher EEG values for Central, Frontal, Parietal, and left Temporal leads. Simple Moment effects were also found, with lower morning values in Temporal and left Frontal recording sites. A Gender x Moment interaction was found at the right Frontal recording site. No significant effects were found for Prefrontal and Occipital recording sites, whatsoever. These results bring new understandings of gender and time of day effects in waking EEG and point to different sensitivity in different cortical areas. The present results could explain some of the observations related to gender differences in cognitive performance.     

Delay discounting in current and never-before cigarette smokers: similarities and differences across commodity,sign, and magnitude

Research has found that nicotine-dependent individuals delay discount monetary gains at a higher rate than matched controls. Delay discount rates, however, have also been found to vary across within-subject variables such as the magnitude of the outcome (e.g., 10 dollars or 1,000 dollars), whether the outcome constitutes a gain or a loss, and the commodity being evaluated (e.g., money or health). The present study comprehensively investigated the differences in delay discounting between current and never-before cigarette smokers and across these within-subject variables. Both groups exhibited a magnitude, sign, and commodity effect. Current smokers' delay discount rates for monetary outcomes, however, were higher than never-before smokers across all magnitudes and both signs. This trend was also found for delayed health outcomes, but failed to reach significance.