Why Does the Average Price of Tuna Fall During Lent?

For many products the average price paid by consumers falls during periods of high demand. We use information from a large supermarket chain to decompose the decrease in the average price into a substitution effect, due to an increase in the share of cheaper products, and a price reduction effect. We find that for almost all the products we study the substitution effect explains a large part of the decrease. We estimate demand for these products and show the price declines are consistent with a change in demand elasticity and the relative demand for different brands. Our findings are less consistent with "loss-leader" models of retail competition.

Why does the average price paid fall during high demand periods?

For many products the average price paid by consumers falls during periods of high demand. We use information from a large supermarket chain to decompose the decrease in the average price into a substitution effect, due to an increase in the share of cheaper products, and a price reduction effect. We find that for almost all the products we study the substitution effect explains a large part of the decrease. We estimate demand for these products and show the price declines are consistent with a change in demand elasticity and the relative demand for different brands. Our findings suggest, that for the data we examine, loss-leader models of retail competition are not the main explanation for price declines

Substance abuse patterns and their association with psychopathology and type of hostility in male patients with borderline and antisocial personality disorder

The aim of this study was to investigate the prevalence of substance use disorder in young adult patients with borderline personality disorder (BPD) and antisocial personality disorder (APD) and to ascertain the specific substances each of these groups choose to abuse. An additional aim was to assess whether alcohol and drug abuse in the patients related to their psychopathology and hostility. The study subjects were 41 hospitalized patients with BPD and 44 hospitalized patients with APD. The diagnoses of personality disorders and substance use disorders were made using DSM-III criteria. Psychopathology patterns were assessed using the Brief psychiatric Rating Scale, Hamilton Depression Rating Scale, and State-Trait Anxiety inventory Hostility was assessed using the Hostility and Direction of Hostility Questionnaire. Abuse of one or more substances was reported by 76% of BPD patients and 95% of APD patients. There was no difference between the two groups in terms of alcohol abuse, but certain substances (such as benzodiazepines, anticholinergics, cannabis, and opioids) were abused more than twice as often by APD patients versus BPD patients. APD patients were more likely than BPD patients to be multiusers. In BPD patients, the number of substances abused showed a negative association with depression, while in APD patients it was positively related to state anxiety. In both patient groups, there was no correlation of the number of abused substances with the degree of extroverted or introverted hostility. Copyright (C) 1999 by W.B. Saunders Company

Discriminating borderline from antisocial personality disorder in male patients based on psychopathology patterns and type of hostility

Dimensions of psychapathology and patterns of hostility, as well as the relationship of hostility to psychopathology, were studied in 85 male young adults: 41 with borderline personality disorder (BPD) and 44 with antisocial personality disorder (APD). Diagnoses were based on DSM-III. The following instruments were also used: Brief Psychiatric Rating Scale, Hamilton Depression Rating scale, State-Trait Anxiety Inventory, and Hostility and Direction of Hostility Questionnaire. BPD patients compared with APD patients showed higher levels of overall psychopathology and depression, whereas both groups had equally high anxiety. Total hostility was quite high in both groups. However, BPD patients had more introverted hostility and APD patients had more extroverted hostility. In BPD patients, introverted hostility was related to overall psychopathology, depression, and trait anxiety, whereas in APD patients, no significant relationship of any type of hostility to various dimensions of psychopathology was observed. In conclusion, when comprehensively assessed, BPD patients can be discriminated from APD patients based on certain dimensions of psychopathology and differences in the direction of their hostility. Moreover, the relationship between psychopathology and hostility patterns suggests that the direction of patients’ hostility plays an important role in the development of disorder-specific symptomatology