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Papers by catarina soares
Journal of East-West Business, 2020
The subprime crisis was a global financial crisis that affected a large number of countries and, ... more The subprime crisis was a global financial crisis that affected a large number of countries and, in particular, the European economies. In this paper we considered fourteen variables associated to the public, private and financial sectors, in order to analyze the main vulnerabilities, differences and similarities observed in twenty-seven European countries. The statistical analysis was performed with the STATIS methodology, with data collected in the period 2002-2011, including some years before and some after the historical crisis of 2007-2008. The study led us to conclude that European countries are different in which concerns to investment, savings, sustainability of public accounts and public investment.
Journal of the Experimental Analysis of Behavior, 2019
We examined how biasing time perception affects choice in a midsession reversal task. Given a sim... more We examined how biasing time perception affects choice in a midsession reversal task. Given a simultaneous discrimination between stimuli S1 and S2, with choices of S1 reinforced during the first, but not the second half of the trials, and choices of S2 reinforced during the second, but not the first half of the trials, pigeons show anticipation errors (premature choices of S2) and perseveration errors (belated choices of S1). This suggests that choice depends on timing processes, on predicting when the contingency reverses based on session duration. We exposed 7 pigeons to a midsession reversal task and manipulated the reinforcement rate on each half of the session. Compared to equal reinforcement rates on both halves of the session, when the reinforcement rate on the first half was lower than on the second half, performance showed more anticipation and less perseveration errors, and when the reinforcement rate on the first half was higher than on the second half, performance showed a remarkable reduction of both types of errors. These results suggest that choice depends on both time into the session and the outcome of previous trials. They also challenge current models of timing to integrate local effects.
Journal of the Experimental Analysis of Behavior
Our goal was to assess the role of timing in pigeons' performance in the midsession reversal task... more Our goal was to assess the role of timing in pigeons' performance in the midsession reversal task. In discrete-trial sessions, pigeons learned to discriminate between 2 stimuli, S1 and S2. Choices of S1 were reinforced only in the first half of the session and choices of S2 were reinforced only in the second half. Typically, pigeons choose S2 before the contingency reverses (anticipatory errors) and S1 after (perseverative errors), suggesting that they time the interval from the beginning of the session to the contingency reversal. To test this hypothesis, we exposed pigeons to a midsession reversal task and, depending on the group, either increased or decreased the ITI duration. We then contrasted the pigeons' performance with the predictions of the Learning-to-Time (LeT) model: In both conditions, preference was expected to reverse at the same time as in the previous sessions. When the ITI was doubled, pigeons' preference reversal occurred at half the trial number but at the same time as in the previous sessions. When the ITI was halved, pigeons' preference reversal occurred at a later trial but at an earlier time than in the previous sessions. Hence, pigeons' performance was only partially consistent with the predictions of LeT, suggesting that besides timing, other sources of control, such as the outcome of previous trials, seem to influence choice.
Journal of East-West Business, 2020
The subprime crisis was a global financial crisis that affected a large number of countries and, ... more The subprime crisis was a global financial crisis that affected a large number of countries and, in particular, the European economies. In this paper we considered fourteen variables associated to the public, private and financial sectors, in order to analyze the main vulnerabilities, differences and similarities observed in twenty-seven European countries. The statistical analysis was performed with the STATIS methodology, with data collected in the period 2002-2011, including some years before and some after the historical crisis of 2007-2008. The study led us to conclude that European countries are different in which concerns to investment, savings, sustainability of public accounts and public investment.
Journal of the Experimental Analysis of Behavior, 2019
We examined how biasing time perception affects choice in a midsession reversal task. Given a sim... more We examined how biasing time perception affects choice in a midsession reversal task. Given a simultaneous discrimination between stimuli S1 and S2, with choices of S1 reinforced during the first, but not the second half of the trials, and choices of S2 reinforced during the second, but not the first half of the trials, pigeons show anticipation errors (premature choices of S2) and perseveration errors (belated choices of S1). This suggests that choice depends on timing processes, on predicting when the contingency reverses based on session duration. We exposed 7 pigeons to a midsession reversal task and manipulated the reinforcement rate on each half of the session. Compared to equal reinforcement rates on both halves of the session, when the reinforcement rate on the first half was lower than on the second half, performance showed more anticipation and less perseveration errors, and when the reinforcement rate on the first half was higher than on the second half, performance showed a remarkable reduction of both types of errors. These results suggest that choice depends on both time into the session and the outcome of previous trials. They also challenge current models of timing to integrate local effects.
Journal of the Experimental Analysis of Behavior
Our goal was to assess the role of timing in pigeons' performance in the midsession reversal task... more Our goal was to assess the role of timing in pigeons' performance in the midsession reversal task. In discrete-trial sessions, pigeons learned to discriminate between 2 stimuli, S1 and S2. Choices of S1 were reinforced only in the first half of the session and choices of S2 were reinforced only in the second half. Typically, pigeons choose S2 before the contingency reverses (anticipatory errors) and S1 after (perseverative errors), suggesting that they time the interval from the beginning of the session to the contingency reversal. To test this hypothesis, we exposed pigeons to a midsession reversal task and, depending on the group, either increased or decreased the ITI duration. We then contrasted the pigeons' performance with the predictions of the Learning-to-Time (LeT) model: In both conditions, preference was expected to reverse at the same time as in the previous sessions. When the ITI was doubled, pigeons' preference reversal occurred at half the trial number but at the same time as in the previous sessions. When the ITI was halved, pigeons' preference reversal occurred at a later trial but at an earlier time than in the previous sessions. Hence, pigeons' performance was only partially consistent with the predictions of LeT, suggesting that besides timing, other sources of control, such as the outcome of previous trials, seem to influence choice.