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Factors affecting long-term memory of aposematic signals in avian predators
Skoumalová, Žaneta ; Exnerová, Alice (advisor) ; Sedláček, František (referee)
The ability to memorize and recognize edible prey from inedible prey is essential for an individuals survival. Many species use aposematic signals for their defense. These are most often represented by distinctive colors or contrast patterns. The aim of this study was to find out in which time the memory consolidation for aposematic pray is achieved and if color or pattern increase its memorability. The choosen model species was the Great tit (Parus major). The comparision was done between handreared naïve birds and wild-caught adults of different age and sex. During the discriminatory task of consolidation experiment, birds were simultaneously presented with palatable and unpalatable prey in the form of paper dummies of bugs, differing in color (red versus green). The birds were divided into three groups with a different interval (0, 1 or 3 hours) for consolidation. The results of consolidation test show that adult birds were more successfull in solving the task than juvenile birds. The only difference between the experimental groups was that the group with one-hour interval achieved better results than other groups. The effect of color of palatable and unpalatable prey on discrimination learning was also found only in adults. Memorability of warning signals was tested using paper bugs of...
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Factors affecting long-term memory of aposematic signals in avian predators
Skoumalová, Žaneta ; Exnerová, Alice (advisor) ; Sedláček, František (referee)
The ability to memorize and recognize edible prey from inedible prey is essential for an individuals survival. Many species use aposematic signals for their defense. These are most often represented by distinctive colors or contrast patterns. The aim of this study was to find out in which time the memory consolidation for aposematic pray is achieved and if color or pattern increase its memorability. The choosen model species was the Great tit (Parus major). The comparision was done between handreared naïve birds and wild-caught adults of different age and sex. During the discriminatory task of consolidation experiment, birds were simultaneously presented with palatable and unpalatable prey in the form of paper dummies of bugs, differing in color (red versus green). The birds were divided into three groups with a different interval (0, 1 or 3 hours) for consolidation. The results of consolidation test show that adult birds were more successfull in solving the task than juvenile birds. The only difference between the experimental groups was that the group with one-hour interval achieved better results than other groups. The effect of color of palatable and unpalatable prey on discrimination learning was also found only in adults. Memorability of warning signals was tested using paper bugs of...
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Psychologically-plausible and connectionism-friendly implementation of long-term memory
Milota, Martin ; Horáček, Jaroslav (advisor) ; Bálek, Martin (referee)
In recent decades, the influence and sophistication of connectionist systems has soared. The fields of their applications are countless - image re- cognition, data mining, robotics, and many more. A part of the thesis focuses on commonly adopted distributed data representations suitable for connectionist systems, devising an extension and testing its usefulness. The goal of the thesis is to use these extensions to design and implement a model of the long-term memory based on a prevalent psychological theory.
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Capital Market Hypotheses and Their Statistical Implications: A Comparative Study
Petras, Petr ; Krištoufek, Ladislav (advisor) ; Křehlík, Tomáš (referee)
In this bachelor thesis we focus on different Market Hypotheses. Specifically on Efficient Market Hypothesis, Fractal Market Hypothesis and Coherent Market Hypothesis. In the first part of the work we provide description of researched hypotheses and methods used for testing. In the second part of the work we run test on time series of share markets, gold markets and currency markets and test if our hypotheses can provide explanation about price changes on those markets. For Efficient Market Hypothesis we wonder if prices are following random walk (via augmented Dickey-Fuller test), if residuals are normally distributed (via Shapiro-Wilk and Jarque-Bera tests) and if residuals are uncorrelated (via Box-Pierce test). For Fractal Market Hypothesis we are trying to find value of Hurst exponent via Rescaled Range analysis. This exponent describes if time series are persistent or not. And for Coherent Market Hypothesis we develop simple method for testing if some time periods can yield above-average revenues, thanks to increased mean and decreased standard deviation. After that we find out what are consequences of short time series and different frequencies for obtaining data points and we learn that some hypotheses describes different time periods or lengths better and are not so good for different ones. Powered...
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