University of Minho

About: University of Minho is a education organization based out in Braga, Portugal. It is known for research contribution in the topics: Context (language use) & Population. The organization has 10585 authors who have published 34736 publications receiving 732436 citations. The organization is also known as: Universidade do Minho & UMinho.

Stock market sentiment lexicon acquisition using microblogging data and statistical measures

Abstract: Lexicon acquisition is a key issue for sentiment analysis. This paper presents a novel and fast approach for creating stock market lexicons. The approach is based on statistical measures applied over a vast set of labeled messages from StockTwits, which is a specialized stock market microblog. We compare three adaptations of statistical measures, such as Pointwise Mutual Information (PMI), two new complementary statistics and the use of sentiment scores for affirmative and negated contexts. Using StockTwits, we show that the new lexicons are competitive for measuring investor sentiment when compared with six popular lexicons. We also applied a lexicon to easily produce Twitter investor sentiment indicators and analyzed their correlation with survey sentiment indexes. The new microblogging indicators have a moderate correlation with popular Investors Intelligence (II) and American Association of Individual Investors (AAII) indicators. Thus, the new microblogging approach can be used alternatively to traditional survey indicators with advantages (e.g., cheaper creation, higher frequencies). Proposal of an automatic procedure for the creation of stock market lexicons.The procedure uses diverse statistical measures on StockTwits labeled messages.The new lexicons obtain better investor sentiment indicators than general lexicons.The new Twitter sentiment indicators correlate with survey sentiment indicators.

Recycling of poly(ethylene terephthalate) as polymer‐polymer composites

Abstract: Microfibrillar reinforced composites (MFC) comprising an isotropic matrix from a lower melting polymer reinforced by microfibrils of a higher melting polymer were manufactured under industrially relevant conditions and processed via injection molding. Low density polyethylene (LDPE) (matrix) and recycled poly(ethylene terephthalate) (PET) (reinforcing material) from bottles were melt blended (in 30/70 and 50/50 PET/LDPE wt ratio) and extruded, followed by continuous drawing, pelletizing and injection molding of dogbone samples. Samples of each stage of MFC manufacturing and processing were characterized by means of scanning electron microscopy (SEM), wide-angle X-ray scattering (WAXS), dynamic mechanical thermal analysis (DMTA), and mechanical testing. SEM and WAXS showed that the extruded blend is isotropic but becomes highly oriented after drawing, being converted into a polymer-polymer composite upon injection molding at temperatures below the melting temperature of PET. This MFC is characterized by an isotropic LDPE matrix reinforced by randomly distributed PET microfibrils, as concluded from the WAXS patterns and SEM observations, the MFC dogbone samples show impressive mechanical properties-the elastic modulus is about 10 times higher than that of LDPE and about three times higher than reinforced LDPE with glass spheres, approaching the modulus of LDPE reinforced with 30 wt% short-glass fibers (GF). The tensile strength is at least two times higher than that of LDPE or of reinforced LDPE with glass spheres, approaching that of reinforced LDPE with 30 wt% GF. The impact strength of LDPE increases by 50% after reinforcement with PET. It is concluded that: (i) the MFC approach can be applied in industrially relevant conditions using various blend partners, and (ii) the MFC concept represents an attractive alternative for recycling of PET as well as other polymers.

Tracking novelties in psychotherapy process research: the innovative moments coding system.

Abstract: This article presents a method for the assessment of innovative moments, which are novelties that emerge in contrast to a client's problematic self-narrative as expressed in therapy, the innovative moments coding system (IMCS). The authors discuss the theoretical background of the IMCS as well as its coding procedures. Results from several studies suggest that the IMCS is a reliable and valid coding system that can be applied to several modalities of psychotherapy. Finally, future research implications are discussed.