Empirical Conjectures Research Articles

Towards a polarized semantics for assertion and denial

Abstract Recent logic and linguistic literature suggest that certain forms of denial cannot be reduced to a simple assertion of negation. In particular, the existence of mathematical and empirical conjectures offers a basis for refuting Frege’s thesis of equivalence between denial and assertion of negation. Following this line of thought we develop a formal framework with two primitive illocutionary operators for assertion and denial, where denial is not a simple negation of assertion. We introduce a semantics for the operators mentioned above. Finally, we discuss the relations between asserted and denied contents.

Quantum Information-Assisted Complete Active Space Optimization (QICAS).

We propose an effective quantum information-assisted complete active space optimization scheme (QICAS). What sets QICAS apart from other correlation-based selection schemes is (i) the use of unique measures from quantum information that assess the correlation in electronic structures in an unambiguous and predictive manner and (ii) an orbital optimization step that minimizes the correlation discarded by the active space approximation. Equipped with these features, QICAS yields, for smaller correlated molecule, sets of optimized orbitals with respect to which the complete active space configuration interaction energy reaches the corresponding complete active space self-consistent field (CASSCF) energy within chemical accuracy. For more challenging systems such as the chromium dimer, QICAS offers an excellent starting point for CASSCF by greatly reducing the number of iterations required for numerical convergence. Accordingly, our study validates a profound empirical conjecture: the energetically optimal nonactive spaces are predominantly those that contain the least entanglement.

Sensorless temperature control of household refrigerators based on the electric current of the compressor

The present study is aimed at putting forward a novel temperature controller (including software and hardware) for a fan-and-damper refrigerator considering the electric current drawn by the single-speed compressor as the process variable. The control algorithm consists in a dynamic reference modification of a PI controller, together with a set of empirical conjectures. In addition, a purpose-built electronic board was designed and prototyped. All experiments were performed in-house with the refrigerator placed in a climate chamber. The refrigerator was tested at two different surrounding air temperatures (16 and 25 °C) under pulldown, defrost recovery, and variable ambient temperature regimes. It was noted that the proposed controller was able to maintain the refrigerator temperature within ±1 °C tolerance bounds – figures like those obtained for the baseline thermistor-based temperature controller – albeit being less costly.

The Impact of GATS on the Insurance Sector: Empirical Evidence from Pakistan

Abstract This study aims to analyse the effects of the General Agreement on Trade in Services (GATS) on the investment activities of the Pakistani insurance sector. First, we analyse the impact of GATS on the overall and company-wise return on investment of the insurance sector of Pakistan. In a panel data setting, the traditional fixed and random effect models are unsuitable for dealing with the possible issues, including endogeneity, unobserved heterogeneity, profit persistency, and the correlation between lagged dependent variables and independent variables. Therefore, we apply the Generalised Method of Moments (GMM) system estimator to the panel data from 1984 to 2018. In the Arellano-Bond framework, the estimated results indicate that the overall investment returns of the Pakistani insurance sector have increased after the GATS membership. However, company-wise analysis reveals mixed evidence. The average returns of IGI Insurance Limited and EFU General Insurance Limited have increased significantly after the GATS membership. These results support one of our empirical conjectures that a rising tide lifts some boats more than it does others. Then, we apply Markowitz’s Portfolio Theory to estimate the portfolio returns and the associated risk using the financial statements data from 1984 to 2018. The estimates of portfolio analysis reveal that the portfolio returns of the Pakistani insurance sector improve by 6.70 percentage points after the membership. However, the associated portfolio risk also increases by 11.13 percentage points, 7.40 times higher than the Pre-GATS risk. Despite the better returns, there is an intensive increase in investment volatility after GATS membership. This study provides a valuable reference for insurance managers and the Ministry of Finance and Securities & Exchange Commission of Pakistan to control and improve the insurance sector’s performance in Pakistan.

Set-theoretic pluralism and the Benacerraf problem

Set-theoretic pluralism is an increasingly influential position in the philosophy of set theory (Balaguer in Platonism and anti-platonism in mathematics, Oxford University Press, New York, 1998; Linksy and Zalta in J Philos 92:525–555, 1995; Hamkins in Rev Symb Log 5:416–449, 2012). There is considerable room for debate about how best to formulate set-theoretic pluralism, and even about whether the view is coherent. But there is widespread agreement as to what there is to recommend the view (given that it can be formulated coherently). Unlike set-theoretic universalism, set-theoretic pluralism affords an answer to Benacerraf’s epistemological challenge. The purpose of this paper is to determine what Benacerraf’s challenge could be such that this view is warranted. I argue that it could not be any of the challenges with which it has been traditionally identified by its advocates, like of Benacerraf and Field. Not only are none of the challenges easier for the pluralist to meet. None satisfies a key constraint that has been placed on Benacerraf’s challenge. However, I argue that Benacerraf’s challenge could be the challenge to show that our set-theoretic beliefs are safe—i.e., to show that we could not have easily had false ones. Whether the pluralist is, in fact, better positioned to show that our set-theoretic beliefs are safe turns on a broadly empirical conjecture which is outstanding. If this conjecture proves to be false, then it is unclear what the epistemological argument for set-theoretic pluralism is supposed to be.

How modular structure can simplify tasks on networks: parameterizing graph optimization by fast local community detection.

By considering the task of finding the shortest walk through a Network, we find an algorithm for which the run time is not as O(2n), with n being the number of nodes, but instead scales with the number of nodes in a coarsened network. This coarsened network has a number of nodes related to the number of dense regions in the original graph. Since we exploit a form of local community detection as a preprocessing, this work gives support to the project of developing heuristic algorithms for detecting dense regions in networks: preprocessing of this kind can accelerate optimization tasks on networks. Our work also suggests a class of empirical conjectures for how structural features of efficient networked systems might scale with system size.

On Ears and Head

The original empirical conjecture of auricular acupuncture (AA) consists of a claim that the entire human body is represented in a certain way on the auricle (eg, in the form of an inverted fetus, see figure 1A), and that the pathology of human organs leads to specific changes at these respective areas on the auricle. It is claimed that these changes can be identified as the areas with skin discolourations, which are tender on palpation. Moreover, the stimulation of these auricular areas, which are supposed to somehow be connected to the organ with ‘pathology’, is believed to improve the functioning of the impaired organ or relieve the related pain.1 The representation of the human body on the auricle is often called ‘somatotopic’, analogous to motor and sensory somatotops of precentral and postcentral gyri of the cortex, as described by Penfield and Rasmussen on the basis of experimental research.2 Interestingly, randomised clinical trials on the efficacy of AA have demonstrated that stimulation of the areas of auricle according to the AA empirical conjecture was effective as complementary treatment for a variety of pain syndromes and preoperative anxiety.3,–,5 However, no neuroanatomical pathways are known to connect the ‘diseased’ organs with the external auricle so that the observed phenomena cannot be explained by the underlying anatomy. Figure 1 (A) The empirical conjecture of auricular acupuncture claims that the entire human body is represented on the auricle in the form of an inverted fetus. (B) Innervation pattern of external auricle. Concha and triangular fossa of the pinna are innervated by the branches of trigeminal and vagal nerves, whereas the peripheral regions of the auricle—helix and scapha—receive their nerve supply …

Sentential Connectives and Translation

In the first exposition of the doctrine of indeterminacy of translation, Quine asserted that the individuation and translation of truth-functional sentential connectives like ‘and’, ‘or’, ‘not’ are not indeterminate. He changed his mind later on, conjecturing that some sentential connectives might be interpreted in different non-equivalent ways. This issue has not been debated much by Quine, or in the subsequent literature, it is, as it were, an unsolved problem, not well understood. For the sake of the argument, I will adopt Quine’s background assumption that all the semantic features of a language can be reduced to the speakers’ dispositions toward assent and dissent, as far as only the truth-conditional core of the meaning of sentences is concerned. I will put forward an argument to the effect that the speech dispositions of most, if not all, English (French, Italian, etc.) speakers constrain a unique translation of their connectives. This argument crucially relies on an empirical conjecture concerning the behaviour of these operators.

Co-payments in the NHS: an analysis of the normative arguments

During 2008, some forms of patient co-payments - in particular, patients paying privately for additional medicines as part of an episode of care in the National Health Service - became controversial in political and policy terms in the UK. In response, the UK Government published a report, the Richards' Review, examining the issues. Richards offered a particular policy solution, but also touched on fundamental principles of social value. Using the methods of normative policy analysis, we seek to understand these principles of social value, accepting the Richards' framework according to which the relevant arguments can be grouped under the broad headings of equity and autonomy. None of the arguments on either side are decisive, and, in part, the policy decision turns on uncertain empirical conjectures.

Informed Trading, Return Synchronicity and Equilibrium Asset Pricing

This paper brings together the traditional asset pricing models, such as the CAPM, with the noisy rational expectations equilibrium models, by investigating two main questions: First, how does heterogeneous private information affect the risk and return of a stock, and second, in such an economy, how does the extent and the kind of information capitalized into prices affect the degree to which stocks move together? I derive a CAPM-like asset pricing relationship where information differences in equilibrium are reflected in asset prices, and the cross-section of expected stock returns is determined by market covariance risk as well as the extent of information heterogeneity in the economy. I then use this equilibrium pricing relationship to examine the theoretical relationship between informed trading and return synchronicity. I find that both market-wide and firm-specific price variation are negatively related to private information precision. This suggests that in contrast to earlier empirical conjectures in the literature, the link between return synchronicity and the amount of information capitalized into prices is tenuous. Finally, I find that while greater noise risk increases the systematic risk of an asset, its effect on firm-specific price variation is ambiguous.

Fermat–Euler Dynamical Systems and the Statistics of Arithmetics of Geometric Progressions

Let n be an integer. A Fermat–Euler dynamical system acts on the set of mod-n residues coprime to n by multiplication by a constant (which is also coprime to n). We study the dependence of the period and the number of orbits of this dynamical system on n. Theorems generalizing Fermat's little theorem, as well as empirical conjectures, are given.

Factorization of Operator Functions in a Hilbert Space

Let \(n\) be an integer. A Fermat-Euler dynamical system acts on the set of mod-\(n\) residues coprime to \(n\) by multiplication by a constant (which is also coprime to \(n\)). We study the dependence of the period and the number of orbits of this dynamical system on \(n\). Theorems generalizing Fermat's little theorem, as well as empirical conjectures, are given.

Does Science Persecute Women? The case of the 16th–17th Century Witch-hunts

I. Logic, rationality and ideologyHerbert Marcuse once claimed that the ‘“rational” is a mode of thought and action which is geared to reduce ignorance, destruction, brutality, and oppression.’ He echoed a widespread folk belief that a world in which people were rational would be a better world. This could be taken as an optimistic empirical conjecture: if people were more rational then probably the world would be a better place (a trust that ‘virtue will be rewarded’, so to speak). However, it is also worth considering a stronger hypothesis: that if something did not reduce ignorance, destruction, brutality, and oppression then it would not constitute rationality. On this view there is no mere correlation between rationality and a propensity toward reduction in ignorance and the rest, it is the propensity to reduce ignorance, destruction, brutality and oppression which in part constitutes rationality. Call this a broad conception of rationality, because it expands beyond the epistemic goal of reducing ignorance, and reaches out to moral concerns like oppression.

COMPONENTS OF VARIANCE MODELS WITH TRANSFORMATIONS

SummaryPower transformations are a popular way to improve the agreement between the observations and the assumptions in a statistical model. In this paper it is assumed that the data, after appropriate power transformation Λ, satisfies a variance components model, with independent Gaussian components. The focus is on inference for quantities which have an interpretation regardless of the choice of Λ (Carroll & Ruppert, 1981) – in particular the intraclass correlation coefficient ρ, the predicted probability of a new observation being less than a specified value and the predicted quantile. It is shown that, in the case Λ= 0, the asymptotic variance of ρ is the same, whether or not one treats Δ as estimated or as known. This supports an empirical conjecture of Solomon (1985). For predicted probabilities and predicted quantiles the variance when A is estimated is shown to be only slightly greater than the variance assuming Δ is known, except in the tails of the distribution where there can be substantial difference between the two variances.

Generating an Optimal Information System: PMAX-SDLC and the Redirection of MIS Research (or How to Help Joe Eat Salmon)

:It is argued that information systems should be treated as any other input into the firm’s production process and, as such, should be selected based on their contribution to the profit of the firm. It is argued that the present systems development life cycle (sdlc) heuristics lead to systems which are feasible and satisficing, but do not lead to a profit maximizing design. An alternative strategy—profit-maximizing systems development life cycle (PMAX-SDLC)—is proposed which is based on the use of process models. These models have their origin in the economics literature and were developed to accurately characterize engineering production processes. Although PMAX-SDLC is more complex than the current sdlc, several empirical conjectures are presented which would support the notion that the potential benefits of redirecting management information systems (mis) research toward optimal systems design could be large.

Scaling Laws for Rydberg Atoms in Magnetic Fields

Empirical conjectures of Feneuille, based on new regularities observed in the quasi-Landau spectrum, are investigated. Scaling laws for Rydberg atoms in magnetic fields are obtained from Schr\"odinger's equation, in two different approximations. Our formulas support the empirical conjectures and show them to be closely connected with the dynamics of the electronic motion in the $z=0$ plane.