Upward Pricing Pressure of Mergers Weakening Vertical Relationships

We modify the UPP test of Farrell and Shapiro (2010) to take into account the possibility that a merger weakens (or eliminates) a vertical supply relationship. After deriving a general effect of the merger, we provide an example of simple estimation strategy when only prices, costs and market shares are available as a snapshot

Transitional probabilities count more than frequency, but might not be used for memorization

Learners often need to extract recurring items from continuous sequences, in both vision and audition. The best-known example is probably found in word-learning, where listeners have to determine where words start and end in fluent speech. This could be achieved through universal and experience-independent statistical mechanisms, for example by relying on Transitional Probabilities (TPs). Further, these mechanisms might allow learners to store items in memory. However, previous investigations have yielded conflicting evidence as to whether a sensitivity to TPs is diagnostic of the memorization of recurring items. Here, we address this issue in the visual modality. Participants were familiarized with a continuous sequence of visual items (i.e., arbitrary or everyday symbols), and then had to choose between (i) high-TP items that appeared in the sequence, (ii) high-TP items that did not appear in the sequence, and (iii) low-TP items that appeared in the sequence. Items matched in TPs but differing in (chunk) frequency were much harder to discriminate than items differing in TPs (with no significant sensitivity to chunk frequency), and learners preferred unattested high-TP items over attested low-TP items. Contrary to previous claims, these results cannot be explained on the basis of the similarity of the test items. Learners thus weigh within-item TPs higher than the frequency of the chunks, even when the TP differences are relatively subtle. We argue that these results are problematic for distributional clustering mechanisms that analyze continuous sequences, and provide supporting computational results. We suggest that the role of TPs might not be to memorize items per se, but rather to prepare learners to memorize recurring items once they are presented in subsequent learning situations with richer cues

Sequential decision making in merger control

We model merger control procedures as a process of sequential acquisition of information and compare US and EU procedures. In the US, the authorities do not have to justify their decision to require further information (issue a second request), whereas in the EU, the authorities face a different (enforceable) standard of proof in phase I relative to phase II. We find that in the absence of remedies, the US procedure is always superior in terms of expected consumer welfare. When we allow for remedies, we find that, compared to the US, merging parties in the EU have more scope to propose remedies in phase I that will preempt the authorities from uncovering unfavorable information in phase II, and this might reduce expected consumer welfare. However, the higher standard of proof in phase I can also in some circumstances act as a commitment not to accept remedies below some threshold and yield a higher expected consumer welfare in the EU. Our model also shows that for global mergers that have the same effect in the two jurisdictions, a decision to trigger a Phase II in the EU yields the same expected consumer welfare as a clearance in Phase I with remedies in the US. However, the converse is not true

Struggling for Structure: cognitive origins of grammatical diversity and their implications for the Human Faculty of Language

There are between 5,000 and 8,000 distinct living languages spoken in the world today that are characterized by both exceptional diversity as well as significant similarities. Many researchers believe that at least part of this ability to communicate with language arises from a uniquely human Faculty of Language (c.f. Hauser, Chomsky, & Fitch, 2002; Pinker & Jackendoff, 2005)

Essays in Competition Economics.

No abstract availableCompetition;

The Causes And Consequences Of Variation In The Insect Immune Response

Plants produce an array of secondary metabolites that play an important ecological role in defense against herbivores in addition to having varied effects on herbivore natural enemies. Here, I investigate the complex interactions between diet, the immune response, and microbiota. In my first experiment, I asked whether plant chemistry and the presence of egg microbes affect the immune response of a specialist herbivore and its resistance to viral attack. Common buckeye larvae (Junonia coenia) were inoculated with a densovirus (JcDNV) and reared on two host plant species (Plantago lanceolata and Plantago major) that differ in their composition and concentration of iridoid glycosides. In addition, a subset of eggs were surface sterilized to investigate whether microbes on the egg’s surface contribute to viral resistance. Survivorship, development time, pupal weight, hemocyte counts, and a colormetric assay of phenoloxidase (PO) enzyme activity were measured to identify what role plant chemistry and microbes play on the outcome of infection by a pathogen, Junonia coenia densovirus. I found that individuals exposed to the virus did not have significantly lower PO activity compared to the unexposed individuals. Survival was significantly higher in individuals feeding on high iridoid diets. Individuals reared from surface sterilized eggs suffered higher mortality from the virus than individuals that were not sterilized, indicating beneficial egg microbes may interfere with viral inoculation success. Individuals feeding on P. lanceolata had significantly larger pupal mass and increased development time as did those larvae that were exposed to the virus. In summary, these results suggest that plant chemistry and egg microbes play an important role in defense against viral enemies and herbivore performance.Insect herbivores represent a model system for investigating complex tri-trophic interactions between their parasitoid counterparts, the insect immune response, and plant defense. The selective pressures from natural enemies and secondary plant metabolites play a key role in driving narrow herbivore diet breadth. In parallel, plants utilize a variety of chemical defense strategies to deter and reduce the fitness of natural enemies via direct and indirect mechanisms. In my second study, I investigated how intraspecific variation of amides in P. cenocladum affect the immune response of associated specialist neotropical caterpillars, Eois apyraria and Eois nympha (Lepidoptera: Geometridae). This plant is defended by colonies of Phiedole bicornis ants that live in the stems and petioles. When the ants are not present P. cenocladum produces high concentrations of three amides: piplartine, cenocladamide, and 4 -desmethylpiplartine. I hypothesized that intraspecific variation of plant chemistry would affect tri-trophic interactions. Specifically, I predicted there would be a positive affecting parasitoid success through the negative effects on the caterpillar immune response. Phenoloxidase activity was measured from 65 Eois caterpillars that were collected from 18 sites across the La Selva Biological station in Costa Rica. Abiotic and biotic factors such as light availability and ant-plant mutualisms that may influence chemotype-mediated effects on the caterpillar immune response were also explored. I concluded that intraspecific chemical variation is influenced by light availability and the presence/absence of ant mutualists. Overall, the immune response of Eois caterpillars was not affected by feeding on host plants that varied in their concentration of Piper amides

Uporaba večpredstavnostne kartografije pri pouku geografije

Multimedia cartography and geography are inextricably linked through cartographic\ud representations that illustrate geographical reality in unique and interesting way. Selected\ud example of spreading urbanization and changing the Municipality of Ljubljana has been\ud presented as a time animation since such representation best shows the geographical process.\ud We know from textbooks and lessons what form of expansion Ljubljana had and still has and\ud what were the historical divides that led to such expansion. The presented multimedia display\ud shows spatial dimension of the geographical process. Display was presented before audience\ud during geography lessons in several different ways. They showed multiple possibilities of\ud spatial data processing and which ways are best suited for illuminating certain geographic\ud phenomena and processes. Geography teaching in this way may be even more interesting and\ud students can easily achieve the required learning objectives. Pupils, students and their teachers\ud presented their views on such a lesson and multimedia cartographic display through the\ud survey questionnaire. From their responses we can conclude that our displays provide enough\ud information for good spatial representation of certain geographical process and are as such\ud appropriate teaching aid for teaching geography.\ud This master's thesis beside making multimedia display, presenting and analysing it with help\ud of users, also offers a detailed theoretical description of multimedia cartography with a view\ud to the future. In this thesis the didactic platform for geography teaching and geography\ud teaching principles, forms and methods are also considered

Rhythmic rhymes for boosting phonological awareness in socially disadvantaged children

This study evaluated the ability for two rhythmic rhyming programs to raise phonological awareness in the early literacy classroom. Year 1s (5-6 year olds) from low socio-economic status schools in Bedfordshire, learned a program of sung or spoken rhythmic rhymes, or acted as controls. The project ran with two independent cohorts (Cohort 1 N= 98, Cohort 2 N= 136). Gains from pre to post tests of phonological awareness (Rhyme Detection, Rhyme Production and Phoneme Deletion), were statistically significant with the exception of Rhyme Detection in the Spoken group (Cohort 1) and Rhyme Production in the Sung group (Cohort 2). The Spoken program achieved medium and large effect sizes for Cohort 1 on measures of rhyming awareness (although the effect size was small for Cohort 2). Comparatively, the Sung program was associated with smaller effects (small, negligible or with a small positive effect for controls) across tasks and cohorts