Includes bibliographical references (p. 10). / "Physics and Mathematics" -t.p. "TID-4500 (15th Ed.)" -t.p.

Cette thèse concerne l'étude de l'interaction air-mer, due aux échanges de mouvements, avec un modèle idéalisé mais consistant. Les études sont réalisées à partir d'un modèle shallow-water bicouches (une pour l'océan et une pour l'atmosphère), avec une fine résolution spatiale et temporelle. L'interaction est uniquement due à la friction de surface entre les deux couches.Elle est implémentée par une loi de friction quadratique. La force appliquée à l'océan est calculée en utilisant la différence de vitesse entre les vents et les courants. Pour la force appliquée à l'atmosphère on distingue deux cas l'interaction ``1way'' et ``2way''. Pour la première, la friction appliquée à l'atmosphère néglige la dynamique de l'océan; elle est calculée en utilisant uniquement les vents. Pour l'interaction ``2W'', la friction appliquée à l'atmosphère est l'opposée de celle appliquée à l'océan.Trois configurations idéalisées sont explorées ici.La première configuration explique la génération d'une instabilité barotrope dans l'océan due à la force de friction quadratique et la dissipation visqueuse horizontale de l'atmosphère. Dans le cas 1W le cisaillement entraîne une instabilité barotrope dans l'océan. Dans le cas 2W, l'instabilité est amplifiée en amplitude et en dimension et est transférée à l'atmosphère. L'échelle principale de cette instabilité correspond à celle du rayon de Rossby dans l'océan. Elle est uniquement visible dans les modèles numériques, lorsque la dynamique est résolue à cette échelle à la fois dans l'océan mais aussi dans l'atmosphère.Dans la deuxième configuration, des expériences pour différentes valeurs du coefficient de traînée de surface sont réalisées. Le forçage diffère de la première configuration, et permet d'avoir une dynamique turbulente dans l'océan et l'atmosphère. L'énergie perdue par l'atmosphère et gagnée par l'océan par cisaillement à l'interface sont déterminées et comparées aux estimations basées sur les vitesses moyennes. La corrélations entre la vorticité océanique et atmosphérique est déterminée à l'échelle synoptique et méso-échelle de l'atmosphère. L'océan a un rôle passif, et absorbe l'énergie cinétique à quasiment tout les instants et tous les lieux. Les résultats différent des études réalisées à l'échelle du bassin. De par les faibles vitesses de l'océan, le transfert d'énergie dépend que faiblement des courants. La dynamique de l'océan laisse cependant son empreinte dans la dynamique de l'atmosphère conduisant à un état `quenched disorder' du système océan-atmosphère, pour le plus fort coefficient de friction utilisé.La dernière configuration, considère l'échange de mouvements entre l'océan et l'atmosphère autour d'une île circulaire. Dans les simulations actuelles de la dynamique océanique, le champs du forçage atmosphérique est généralement trop grossier pour inclure la présence de petites îles (<100km). Dans les calculs présentés ici, l'île est représenté dans la couche atmosphérique par un coefficient de traînée cent fois plus fort au dessus de l'île que l'océan. Cela engendre de la vorticité dans l'atmosphère , autour et près du sillage de l'île. L'influence de la vorticité atmosphérique sur la vorticité de l'océan, l'upwelling, la turbulence et le transfert d'énergieest considéré en utilisant des simulations couplées océan-atmosphère.Les résultats sont comparés avec des simulations ayant un forçage atmosphérique constant dans le temps et l'espace (pas de sillage) et des simulations "1W" (pour lesquelles les courants n'ont pas d'influence sur l'atmosphère).Les résultats des simulations sont en accords avec les travaux et les observations précédemment réalisés, et confirment que le sillage atmosphérique est le principal processus générant des tourbillons océanique dans le lit de l'île. Il est aussi montré que la vorticité est injectée directement par le rotationel du vent, mais aussi par la force du vent perpendiculaireau gradient d'épaisseur de la couche de surface océanique. / This thesis considers air-sea interaction, due to momentum exchange, in an idealized but consistent model. Two superposed one-layer fine-resolution shallow-water models are numerically integrated. The upper layer represents the atmosphere and the lower layer the ocean. The interaction is only due to the shear between the two layers. The shear applied to the ocean is calculated using the velocity difference between the ocean and the atmosphere.The frictional force between the two-layers is implemented using the quadratic drag law. Three idealized configurations are explored.First, a new mechanism that induces barotropic instability in the ocean is discussed. It is due to air-sea interaction with a quadratic drag law and horizontal viscous dissipation in the atmosphere. I show that the instability spreads to the atmosphere. The preferred spatial scale of the instability is that of the oceanic baroclinic Rossby radius of deformation.It can only be represented in numerical models, when the dynamics at this scale is resolved in the atmosphere and the ocean.In one-way interaction the shear applied to the atmosphere neglectsthe ocean dynamics, it is calculated using the atmospheric wind, only. In two-way interaction it is opposite to the shear applied to the ocean.In the one-way interaction the atmospheric shear leads to a barotropic instability in the ocean. The instability in the ocean is amplified, in amplitude and scale, in two-way interaction and also triggers an instability in the atmosphere.Second, the air-sea interaction at the atmospheric synoptic and mesoscale due to momentum transfer, only, is considered. Experiments with different values of the surface friction drag coefficient are performed, with a different atmospheric forcing from the first configuration, that leads to a turbulent dynamics in the atmosphere and the ocean. The actual energy loss of the atmosphere and the energy gain by the ocean, due to the inter-facial shear,is determined and compared to the estimates based on average speeds.The correlation between the vorticity in the atmosphere and the ocean is determined. Results differ from previous investigations where the exchange of momentum was considered at basin scale. It is shown that the ocean has a passive role, absorbing kinetic energy at nearly all times and locations.Due to the feeble velocities in the ocean, the energy transfer depends only weakly on the ocean velocity. The ocean dynamics leaves nevertheless its imprint in the atmospheric dynamics leading to a quenched disordered state of the atmosphere-ocean system, for the highest value of the friction coefficient considered. This finding questions the ergodic hypothesis, which is at the basis of a large number of experimental, observational and numericalresults in ocean, atmosphere and climate dynamics.The last configuration considers the air-sea interaction, due to momentum exchange, around a circular island. In todays simulations of the ocean dynamics, the atmospheric forcing fields are usually too coarse to include the presence of smaller islands (typically $<$ 100km).In the calculations presented here, the island is represented in the atmospheric layer by a hundred fold increased drag coefficient above the island as compared to the ocean. It leads to an increased atmospheric vorticity in the vicinity and in the wake of the island. The influence of the atmospheric vorticity on the ocean vorticity, upwelling, turbulence and energy transfer is considered by performing fully coupled simulations of the atmosphere-oceandynamics. The results are compared to simulations with a constant, in space and time, atmospheric forcing (no wake) and simulations with one-waycoupling only (where the ocean velocity has no influence on the atmosphere).Results of our simulations agree with previous published work and observations, and confirm that the wind-wake is the main process leading to mesoscale oceanic eddies in the lee of an island.

The energy-momentum tensor (EMT) is the Noether current associated with translations. It is of interest because, first of all, it has physical meaning as it contains the energy density and the momentum density. Moreover, its trace can be related to the beta function so that the scaling behaviour of the theory at hand can be studied. We are particularly interested in the scaling behaviour of strongly coupled theories. To explore the strong coupling regime it is necessary to compute the EMT non-perturbatively, i.e. on the lattice. This complicates matters greatly. On the lattice translation invariance is broken which leads to additional terms in the translation Ward identity from which the EMT is derived. This results in turn in the need to renormalise the EMT on the lattice. In this thesis we extend recent studies on the renormalisation of the EMT in four-dimensional gauge theory to the case of a three-dimensional scalar theory to investigate its divergence structure and the numerical feasibility of the suggested procedure on a more basic level. Furthermore, scalar φ4-theory in three dimensions exhibits an infrared fixed point and can thus serve as a toy model to examine mechanisms for building theories beyond the standard model. Our strategy to renormalise the EMT on the lattice is to identify all possible terms that can mix with both sides of the translation Ward identity. The renormalised EMT is a combination of operators of the same or lower dimension obeying the symmetries of the theory. The mixing is determined by requiring that the renormalised EMT satisfies the correct Ward identities. Using different probes in the translation Ward identity one can compute the coefficients of the EMT by solving a linear system of equations. However, contact terms can arise. One solution is the recently introduced Wilson flow. Its renormalisation properties allow for expectation values free of contact terms. That way the Wilson flow provides for a meaningful theoretical formulation of the EMT on the lattice that can be used in practice. In this thesis we review the renormalisation properties and the phase diagram of scalar φ4-theory in three dimensions, the translation Ward identity and the EMT in the continuum, as well as the gradient flow for scalar theory. A large part is dedicated to the perturbative renormalisation of the EMT on the lattice. Finally, our strategy to compute the renormalisation constants of the EMT in scalar theory non-perturbatively is discussed in detail, and our results for the renormalisation constants are presented.

Submitted by MFEE Mestrado Profissional em Finanças e Economia Empresarial da EPGE (mfee@fgv.br) on 2015-02-24T19:52:06Z No. of bitstreams: 1 Daniel Pádua Versão Final.pdf: 2926735 bytes, checksum: 3a118ec117860cba182feae37fa5226f (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-03-03T19:10:36Z (GMT) No. of bitstreams: 1 Daniel Pádua Versão Final.pdf: 2926735 bytes, checksum: 3a118ec117860cba182feae37fa5226f (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-03-03T19:11:22Z (GMT) No. of bitstreams: 1 Daniel Pádua Versão Final.pdf: 2926735 bytes, checksum: 3a118ec117860cba182feae37fa5226f (MD5) / Made available in DSpace on 2015-03-03T19:11:40Z (GMT). No. of bitstreams: 1 Daniel Pádua Versão Final.pdf: 2926735 bytes, checksum: 3a118ec117860cba182feae37fa5226f (MD5) Previous issue date: 2013-01-29 / Wahal and Cruz (2009) published an essay adding to the literature on behavior fínance, unifying the concepts of momentum, comovement and style investing as tools for return predictability. They discovered that assets possessing larger comovement offered higher returns as opposed to those having low comovement. We endeavored to reflect their methodology to the Brazilian market in a matmer applicable scenario of low liquidity and reduced amount of asscts that are charactetistics o f our stock market. Our results did not present the same tendency of the original essay, but we verifíed that, albeit in a limited way, it is possible to explore profítable strategies by means ofusing this structure. / Wahal e Yavuz (2009) divulgaram trabalho ampliando a literatura da teoria de finanças comportamentais, unindo os conceitos de momento, estilo e comovimento como ferramentas de previsibilidade de retorno em investimentos. Eles descobriram que ativos com maior comovimento apresentam retornos mais elevados que os de baixo comovimento. Buscamos replicar a sua metodologia ao mercado brasileiro de maneira aplicável a realidade de baixa liquidez e quantidade reduzida de ativos do nosso mercado de ações. Nossos resultados não apresentaram a mesma tendência do trabalho original, porém verificamos, ainda que de forma limitada, a possibilidade de explorar estratégias lucrativas usando este arcabouço.

This thesis is an attempt to bridge some research gaps in the area of behavioural finance and investment through adopting the three essays scheme of PhD dissertations. There is a widespread belief that the traditional finance theory failed to provide a sufficient and plausible explanation for (1) what motivates individual investors to trade, (2) the pattern of their trading and the formation of their portfolios, (3) the determinants of cross section of expected returns other than risk. Behavioural Finance, however, offers more realistic assumptions based on two building blocks; behavioural biases of irrational investors and the limits of arbitrage that prevent the arbitrageurs from correcting mispricing and pushing prices back to fundamental values. This dissertation is structured as follows: In the first essay, the disposition effect is defined as the propensity of investors to realize gains too early while being loath to realize losses. Capital gains overhang is a measure of unrealized capital gains and losses that is associated with the disposition effect and the trading activities of behaviourally biased investors. We discover that firm characteristics can play a role in explaining variations in the capital gains overhang that is consistent with the activities of behaviourally biased and disposition investors. Specifically, we find that capital gains overhang is increasing in firm attributes that attract behaviourally biased investors, namely, earnings per share, leverage, growth and size. Capital gains overhang is also declining in market liquidity, possibly because liquidity allows behaviourally biased investors to excessively trade shares and beta and corporate earnings, probably because when high risk and inefficient firms experience losses, disposition investors experience capital losses that they are reluctant to realize. In the second essay, quantile regressions are employed to analyse the relationship between the unrealized capital gains overhang and expected returns. The ability of the disposition effect to generate momentum is also considered for the extreme expected return regions (0.05th) and (0.95th) quantiles. To do so, 450,617 observations belonging to 5176 US firms are employed, covering a time span from January 1998 to June 2015. Following the methodology of Grinblatt and Han (2005), the findings show significant differences across various quantiles in terms of signs and magnitudes. These findings indicate a nonlinear relationship between capital gains overhang and expected returns since the impact of capital gains overhang as a proxy for disposition effect on expected returns vary across the expected return distribution. More precisely, the coefficients of capital gains overhang are significantly positive and decline as the expected returns quantiles increase from the lowest to the median expected return quantiles. However, they become significantly negative and rise with the increase in expected returns quantiles above median expected returns quantiles. The findings also suggest that the disposition effect is not a good noisy proxy for momentum at the lowest expected return quantile (0.05th). However, interestingly it seems to generate contrarian in returns at the highest expected returns quantile (0.95th). In the third essays, we try to discover systematic disagreements in momentum, asymmetric volatility and the idiosyncratic risk momentum return relationship between high-tech stocks and low-tech stocks. We develop several hypotheses that suggest greater momentum profits, fainter asymmetric volatility and weaker idiosyncratic risk-momentum return relation in the high-tech stocks relative to the low tech stocks. To this end, we divide 5795 stocks that are listed in the Russell 3000 index from January 1995 to December 2015 into two samples SIC code and analysed them using the Fama French with GJR-GARCH-M term. The results show that the high-tech stocks provide greater momentum profits especially for portfolios that have holding and ranking periods of less than 12 months. In most cases momentum returns in the high-tech stocks explain a symmetric response to good and bad news while the momentum returns in the low-tech stocks show an asymmetric response. Finally, the idiosyncratic risk-momentum return relation is insignificant for high-tech stocks while it is significant and negative for low-tech stocks. That is, as idiosyncratic risk increases, momentum decreases for low-tech stocks. These findings are robust to different momentum strategies and to different breakpoints.

Several variables have been shown to influence resistance to change including rate, magnitude, and delay to reinforcement (Nevin, 1974). One variable that has not been studied with humans concerns the evaluation of resistance to change with unconditioned and conditioned reinforcers. In Experiment 1 (Resistance to Extinction Assessment), 5 participants' behaviors were reinforced during a baseline phase on a mult VI 30 s VI 30 s schedule with either a conditioned (i.e., token) or unconditioned reinforcer (i.e., food). Following equal reinforcement rates across components, extinction was introduced as a disruptor. All participants showed greater resistance to extinction in the component associated with conditioned reinforcers than unconditioned reinforcers. In Experiment 2 (Varied Distractors Assessment), 4 participants experienced a baseline phase the same as Experiment 1 (i.e., mult VI 30 s VI 30 s). Each participant was then exposed to prefeeding and distraction as disruptors in separate analyses. Results showed that behaviors were more resistant to distraction with conditioned than unconditioned reinforcers, similar to Experiment 1. However, when prefeeding disrupted responding, greater resistance to change was observed with unconditioned reinforcers than conditioned reinforcers. Implications of the results are discussed.

Submitted by JOHN HADDER SANDOVAL QUESADA null (jsandoval@ift.unesp.br) on 2016-03-21T13:14:37Z No. of bitstreams: 1 Thesis.pdf: 687348 bytes, checksum: 6368301fa02619d10860d9db3bec7418 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-03-22T14:28:16Z (GMT) No. of bitstreams: 1 quesada_jhs_me_ift.pdf: 687348 bytes, checksum: 6368301fa02619d10860d9db3bec7418 (MD5) / Made available in DSpace on 2016-03-22T14:28:16Z (GMT). No. of bitstreams: 1 quesada_jhs_me_ift.pdf: 687348 bytes, checksum: 6368301fa02619d10860d9db3bec7418 (MD5) Previous issue date: 2016-01-28 / Outra / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho foca no estudo de sistemas de poucos corpos em duas dimensões no regime universal, onde as propriedades do sistema quântico independem dos detalhes da interação de curto alcance entre as partículas (o comprimento de espalhamento de dois corpos é muito maior que o alcance do potencial). Nós utilizamos a decomposição de Faddeev para escrever as equações para os estados ligados. Através da solução numérica dessas equações nós calculamos as energias de ligação e os raios quadráticos médios de um sistema composto por dois bósons (A) e uma partícula diferente (B). Para uma razão de massas mB/mA = 0.01 o sistema apresenta oito estados ligados de três corpos, os quais desaparecem um por um conforme aumentamos a razão de massas restando somente os estados fundamental e primeiro excitado. Os comportamentos das energias e dos raios para razões de massa pequenas podem ser entendidos através de um potencial do tipo Coulomb a curtas distâncias (onde o estado fundamental está localizado) que aparece quando utilizamos uma aproximação de Born-Oppenheimer. Para grandes razões de massa os dois estados ligados restantes são consistentes com uma estrutura de três corpos mais simétrica. Nós encontramos que no limiar da razão de massas em que os estados desaparecem os raios divergem linearmente com as energias de três corpos escritas em relação ao limiar de dois corpos. / This work is focused in the study of two dimensional few-body physics in the universal regime, where the properties of the quantum system are independent on the details of the short-range interaction between particles (the two-body scatter- ing length is much larger than the range of the potential). We used the Faddeev decomposition to write the bound-state equations and we calculated the three-body binding energies and root-mean-square (rms) radii for a three-body system in two dimensions compounded by two identical bosons (A) and a different particle (B). For mass ratio mB/mA = 0.01 the system displays eight three-body bound states, which disappear one by one as the mass ratio is increased leaving only the ground and the first excited states. Energies and radii of the states for small mass ratios can be understood quantitatively through the Coulomb-like Born-Oppenheimer potential at small distances where the lowest-lying of these states are located. For large mass ratio the radii of the two remaining bound states are consistent with a more sym- metric three-body structure. We found that the radii diverge linearly at the mass ratio threshold where the three-body excited states disappear. The divergences are linear in the inverse energy deviations from the corresponding two-body thresholds. / MEC: 243164-72 / MEC: 243745-72

En 1972, Skumanich découvre une relation empirique unique entre la période de rotation de surface des étoiles G et leur âge sur la séquence principale. Cette découverte ouvrit alors une nouvelle voie pour la datation stellaire : la gyrochronologie. Dès lors, bon nombre d'auteurs, entre la fin des années 80 et 90, se sont intéressés à l'évolution de la vitesse de rotation de surface des étoiles de faible masse ($M_*$ = 0.4 $M_{odot}$- 1.1 $M_{odot}$). Les premiers modèles phénoménologies sur le sujet été nés.L'évolution de la vitesse de rotation de ces étoiles commence à être raisonnablement bien reproduite par la classe de modèle paramétrique que je présente dans cette thèse. Par manque de descriptions théoriques satisfaisantes, seuls les effets globaux des mécanismes physiques impliqués sont ici décris. Le principal enjeu est d'étudier le cadre et la façon dont le moment cinétique stellaire est impacté par ces processus tout en contraignant leurs principales caractéristiques.Au cours de ma thèse, j'ai modélisé les trajets rotationnels des enveloppes externes et médianes des distributions de période de rotation de 18 amas stellaire entre 1 Myr et 1 Gyr. Ceci m'a permis d'analyser la dépendance temporelle des mécanismes physiques impliqués dans l'évolution du moment cinétique des étoiles de type solaire. Les résultats que j'ai obtenus montrent que l'évolution de la rotation différentielle interne impact fortement la convergence rotationnelle (relation empirique de Skumanich), l'évolution de l'abondance de surface en lithium, et les intensités du champ magnétique généré par effet dynamo. En plus de reproduire ces enveloppes externes, le modèle que j'ai développé fournit des contraintes sur les mécanismes de redistribution interne du moment cinétique et sur les durées de vie des disques circumstellaires, supposés responsables de la régulation rotationnelle observée durant les quelques premiers millions d'années de la pré-séquence principale. L'extension du modèle aux étoiles moins massives (0.5 et 0.8 $M_{odot}$) que j'ai réalisé, a également fournis la dépendance en masse de ces différents processus physiques.Cette étape à notamment ajoutée de fortes contraintes sur les temps caractéristiques associés au transport de moment cinétique entre le coeur et l'enveloppe, sur l'efficacité du freinage magnétique vraisemblablement reliée à un changement de topologie des étoiles de type solaire vers celles de 0.5 $M_{odot}$, et sur l'histoire rotationnelle, interne comme de surface, des étoiles entre 1 Myr à 1 Gyr. / In 1972, Skumanich discovers a unique empirical relationship between the rotation period of the surface of G star and their age on the main sequence. This discovery then opened a new path for stellar dating: the gyrochronology. Therefore, many authors in the late 80's and the begenning 90's, were interested in the evolution of the surface angular velocity of low-mass stars ($M_*$ = 0.4 $M_{odot}$- 1.1 $M_{odot}$). The first phenomenological models on the subject were born.The angular velocity evolution of these stars begins to be reasonably well reproduced by the class of parametrical model that I present in this thesis. Because of the lack of adequate theoretical descriptions, only the overall effects of the physical mechanisms involved are described here. The main issue is to study the framework and how the stellar angular momentum is affected by these processes and to constrain their main characteristics.Over the course of my thesis, I modelled the rotational tracks of external and median envelopes and median of rotation period distributions of 18 stellar clusters between 1 Myr and 1 Gyr. This allowed me to analyse the time dependence of the physical mechanisms involved in the angular momentum evolution of solar-type stars. The results I obtained show that the evolution of the internal differential rotation significantly impact the rotational convergence (empirical Skumanich's relationship), the evolution of the surface lithium abundance, and the intensity of the magnetic field generated by dynamo effect. In addition to the reproduction of these external envelopes, the model I developed provides constraints on the mechanisms of internal redistribution of angular momentum and the lifetimes of circumstellar disks, that are held responsible for the rotational regulation observed during the first few million years of pre-main sequence. The extension of the model to less massive stars (0.5 et 0.8 $M_{odot}$) that I performed also provided the mass dependence of these physical processes. Most specifically, this step added strong constraints on the characteristic time associated to the transport of angular momentum between the core and the envelope, on the efficiency of magnetic braking likely related to a change of topology from solar-type stars to those of 0.5 $M_{odot}$, and on the internal and external rotational history of stars from 1 Myr to 1 Gyr.

Debatten kring huruvida det är möjligt att överavkasta aktiemarknaden över tid har existerat i många år. Forskare som Eugene Fama (1965) konkluderar att aktiemarknader i allmänhet är effektiva och menar att högre avkastning inte kan genereras utan ökat risktagande. Andra forskare som exempelvis Shiller (2003) har dock dragit slutsatsen att det finns investeringsstrategier som överavkastar marknaden över tid. Denna studie syftar till att undersöka effektiviteten på den nordiska aktiemarknaden genom att utvärdera prestationen av olika portföljer sammansatta av utvalda nyckeltal. Vidare utreder författarna huruvida valet av beräkningsmodell påverkar bedömningen av portföljernas prestationer.   Studien utreder samtliga kombinationer av variablerna EV/S, EV/EBIT och momentum. De första två nyckeltalen beaktar bolagets värde (EV) i relation till dess försäljning (S) respektive vinst (EBIT). Den tredje variabeln som undersöks i studien är momentum, vilket är en indikator som används för att finna de aktier som ökat mest i pris den senaste tiden. Tidigare forskning visar att kombinationen av värdeaktier (exempelvis EV/S och EV/EBIT) och momentum kan generera överavkastning tack vare en negativ korrelation mellan variablerna. För att utreda hur samtliga kombinationer presterar så skapas portföljer sammansatta av de olika nyckeltalen. Studien undersöker hur portföljerna presterar över en tioårsperiod på den nordiska aktiemarknaden. Portföljerna utvärderas med hjälp av tre olika teoretiska beräkningsmodeller som alla är vedertagna inom anomali-forskningen. Capital Asset Pricing Model (CAPM) skattar portföljers avkastning baserat på den tagna risken, trefaktormodellen inkluderar även proportionen småbolag och andelen värdeaktier medan fyrfaktormodellen inkorporerar momentum som en ytterligare faktor.     Studien resulterar i att fem av de totalt sju portföljerna genererar en riskjusterad avkastning som skiljer sig från marknaden. Författarna kan konkludera att tre av dessa överavkastar marknaden medan två uppvisar en lägre riskjusterad avkastning än index. Portföljer innehållandes nyckeltalet EV/S presterar generellt sett undermåligt medan EV/EBIT ingår i flertalet framgångsrika portföljer.  Författarna kan se tendenser till att kombinationer av värdenyckeltal genererar extra värde samt att momentum i kombination med värdenycketal verkar vara fördelaktigt. De sistnämnda slutsatserna kan dock inte statistiskt säkerställas eftersom ingen av de undersökta kombinationerna var signifikant bättre än beståndsdelarna separat. Beroende på vilken av CAPM, trefaktormodellen eller fyrfaktormodellen som används för att skatta portföljernas prestationer varierar antalet signifikanta överpresterande portföljer. Författarna drar därav slutsatsen att det är viktigt att betänka valet av vilken beräkningsmodell som bör tillämpas för att skatta portföljernas riskjusterade avkastning.

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