Time-Slice Rationality and Self-Locating Belief

The epistemology of self-locating belief concerns itself with how rational agents ought to respond to certain kinds of indexical information. I argue that those who endorse the thesis of Time-Slice Rationality ought to endorse a particular view about the epistemology of self-locating belief, according to which ‘essentially indexical’ information is never evidentially relevant to non-indexical matters. I close by offering some independent motivations for endorsing Time-Slice Rationality in the context of the epistemology of self-locating belief

Processing indexical information demands resources: Evidence from the change deafness paradigm.

Information about talker identity, referred to as indexical information, and the way it is processed in spoken word recognition is a topic of much debate. Current theories of spoken word recognition suggest indexical information is either removed entirely or encoded in its entirety. Recent research found that the amount of time spent processing the speech stream affects the amount of indexical information available to a listener. These effects suggest that the processing of indexical information is a resource demanding process. The current study uses the change deafness paradigm to examine both explicitly and implicitly the ability of participants to accurately detect a change between two speakers at the conclusion of an auditory lexical decision task. The results demonstrate that variable rates of processing affect the participants' ability to accurately detect a change in speaker, suggesting that the processing of indexical information is a resource demanding process

Voices in the mental lexicon: Words carry indexical information that can affect access to their meaning

Available online 11 May 2019The speech signal carries both linguistic and non-linguistic information (e.g., a talker’s voice qualities; referred to as indexical information). There is evidence that indexical information can affect some aspects of spoken word recognition, but we still do not know whether and how it can affect access to a word’s meaning. A few studies support a dual-route model, in which inferences about the talker can guide access to meaning via a route external to the mental lexicon. It remains unclear whether indexical information is also encoded within the mental lexicon. The present study tests for indexical effects on spoken word recognition and referent selection within the mental lexicon. In two experiments, we manipulated voice-to-referent co-occurrence, while preventing participants from using indexical information in an explicit way. Participants learned novel words (e.g., bifa) and their meanings (e.g., kite), with each talker’s voice linked (via systematic co-occurrence) to a specific referent (e.g., bifa spoken by speaker 1 referred to a specific picture of a kite). In testing, voice-to-referent mapping either matched that of training (congruent), or not (incongruent). Participants’ looks to the target’s referent were used as an index of lexical activation. Listeners looked faster at a target’s referent on congruent than incongruent trials. The same pattern of results was observed in a third experiment, when testing was 24 hrs later. These results show that indexical information can be encoded in lexical representations and affect spoken word recognition and referent selection. Our findings are consistent with episodic and distributed views of the mental lexicon that assume multi-dimensional lexical representations.Support for this project was provided by the Spanish Ministry of Science and Innovation, Grant # PSI2014-53277 and # PSI2017-82563- P awarded to A.G.S., the Spanish Ministry of Economy and Competitiveness, Juan de la Cierva-Formación fellowship awarded to E.C.K., and the Spanish Ministry of Economy and Competitiveness, “Severo Ochoa” Programme for Centres/Units of Excellence in R&D (SEV‐2015‐490)

Perceptual integration of indexical information in bilingual speech

The present research examines how different types of indexical information, namely talker information and the language being spoken, are perceptually integrated in bilingual speech. Using a speeded classification paradigm (Garner, 1974), variability in characteristics of the talker (gender in Experiment 1 and specific talker in Experiment 2) and in the language being spoken (Mandarin vs. English) was manipulated. Listeners from two different language backgrounds, English monolinguals and Mandarin-English bilinguals, were asked to classify short, meaningful sentences obtained from different Mandarin-English bilingual talkers on these indexical dimensions. Results for the gender-language classification (Exp. 1) showed a significant, symmetrical interference effect for both listener groups, indicating that gender information and language are processed in an integral manner. For talker-language classification (Exp. 2), language interfered more with talker than vice versa for the English monolinguals, but symmetrical interference was found for the Mandarin-English bilinguals. These results suggest both that talker-specificity is not fully segregated from language-specificity, and that bilinguals exhibit more balanced classification along various indexical dimensions of speech. Currently, follow-up studies investigate this talker-language dependency for bilingual listeners who do not speak Mandarin in order to disentangle the role of bilingualism versus language familiarity

Speaker Sex Influences Processing of Grammatical Gender

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author’s publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Spoken words carry linguistic and indexical information to listeners. Abstractionist models of spoken word recognition suggest that indexical information is stripped away in a process called normalization to allow processing of the linguistic message to proceed. In contrast, exemplar models of the lexicon suggest that indexical information is retained in memory, and influences the process of spoken word recognition. In the present study native Spanish listeners heard Spanish words that varied in grammatical gender (masculine, ending in -o, or feminine, ending in -a) produced by either a male or a female speaker. When asked to indicate the grammatical gender of the words, listeners were faster and more accurate when the sex of the speaker “matched” the grammatical gender than when the sex of the speaker and the grammatical gender “mismatched.” No such interference was observed when listeners heard the same stimuli, but identified whether the speaker was male or female. This finding suggests that indexical information, in this case the sex of the speaker, influences not just processes associated with word recognition, but also higher-level processes associated with grammatical processing. This result also raises questions regarding the widespread assumption about the cognitive independence and automatic nature of grammatical processes

Prediction and explanation in the multiverse

Probabilities in the multiverse can be calculated by assuming that we are typical representatives in a given reference class. But is this class well defined? What should be included in the ensemble in which we are supposed to be typical? There is a widespread belief that this question is inherently vague, and that there are various possible choices for the types of reference objects which should be counted in. Here we argue that the ``ideal'' reference class (for the purpose of making predictions) can be defined unambiguously in a rather precise way, as the set of all observers with identical information content. When the observers in a given class perform an experiment, the class branches into subclasses who learn different information from the outcome of that experiment. The probabilities for the different outcomes are defined as the relative numbers of observers in each subclass. For practical purposes, wider reference classes can be used, where we trace over all information which is uncorrelated to the outcome of the experiment, or whose correlation with it is beyond our current understanding. We argue that, once we have gathered all practically available evidence, the optimal strategy for making predictions is to consider ourselves typical in any reference class we belong to, unless we have evidence to the contrary. In the latter case, the class must be correspondingly narrowed.Comment: Minor clarifications adde

Does Talker Familiarity or Time of Testing Facilitate Sentence Recognition When Listening in Noise?

At the most elementary level, the speech signal is comprised of two parts: linguistic information and indexical information. The linguistic information is the phonetic information of the signal and indexical information is speaker specific and is the paralinguistic information of the signal. Part of this indexical information is talker specific characteristics; which have been shown to help people understand speech. The talker specific characteristic we looked at was talker familiarity. Talker familiarity has been shown to help babies segment speech and adults listen in noise and recall stories. We looked at talker familiarity to see if it would benefit typically developing adults listen in ecologically valid background noise. Our hypotheses were: two significant main effects and interaction. Our study had two independent variables; talker (familiar, novel) and time of testing (Time 1, Time 2) and the dependent variable was keyword accuracy. A total of 93 individuals participated in this study; 41 of which were familiar with the talker due to the talker being their university professor. Our results showed a main effect of talker and a main effect of time of testing but there was no interaction between talker and time of testing. Implications are discussed

Puzzles of Anthropic Reasoning Resolved Using Full Non-indexical Conditioning

I consider the puzzles arising from four interrelated problems involving `anthropic' reasoning, and in particular the `Self-Sampling Assumption' (SSA) - that one should reason as if one were randomly chosen from the set of all observers in a suitable reference class. The problem of Freak Observers might appear to force acceptance of SSA if any empirical evidence is to be credited. The Sleeping Beauty problem arguably shows that one should also accept the `Self-Indication Assumption' (SIA) - that one should take one's own existence as evidence that the number of observers is more likely to be large than small. But this assumption produces apparently absurd results in the Presumptuous Philosopher problem. Without SIA, however, a definitive refutation of the counterintuitive Doomsday Argument seems difficult. I show that these problems are satisfyingly resolved by applying the principle that one should always condition on all evidence - not just on the fact that you are an intelligent observer, or that you are human, but on the fact that you are a human with a specific set of memories. This `Full Non-indexical Conditioning' (FNC) approach usually produces the same results as assuming both SSA and SIA, with a sufficiently broad reference class, while avoiding their ad hoc aspects. I argue that the results of FNC are correct using the device of hypothetical ``companion'' observers, whose existence clarifies what principles of reasoning are valid. I conclude by discussing how one can use FNC to infer how densely we should expect intelligent species to occur, and by examining recent anthropic arguments in inflationary and string theory cosmology

An Infrared Divergence Problem in the cosmological measure theory and the anthropic reasoning

An anthropic principle has made it possible to answer the difficult question of why the observable value of cosmological constant ($\Lambda\sim 10^{-47}$ GeV${}^4$) is so disconcertingly tiny compared to predicted value of vacuum energy density $\rho_{SUSY}\sim 10^{12}$ GeV${}^4$. Unfortunately, there is a darker side to this argument, as it consequently leads to another absurd prediction: that the probability to observe the value $\Lambda=0$ for randomly selected observer exactly equals to 1. We'll call this controversy an infrared divergence problem. It is shown that the IRD prediction can be avoided with the help of a Linde-Vanchurin {\em singular runaway measure} coupled with the calculation of relative Bayesian probabilities by the means of the {\em doomsday argument}. Moreover, it is shown that while the IRD problem occurs for the {\em prediction stage} of value of $\Lambda$, it disappears at the {\em explanatory stage} when $\Lambda$ has already been measured by the observer.Comment: 9 pages, RevTe