When Does a Mutual Fund's Trade Reveal its Skill?

We conjecture that a mutual fund manager with superior stock selection ability is more likely to benefit from trading in stocks affected by information-events. Taking the probability of informed trading (PIN, Easley, Kiefer, O'Hara, and Paperman, 1996) to measure the amount of informed trading in a stock, and inferring mutual fund trades from a large sample of mutual fund holdings, we provide empirical support for the conjecture. Funds trading high-PIN stocks exhibit superior performance on average, and superior performance that is more likely to persist. The findings are not due to price momentum or the higher returns earned by high-PIN stocks on average. Conclusions remain the same after testing for alternative measures for the amount of informed trading. Decomposing a fund's stock selection ability into "informed trading" and "liquidity provision" adds further insight into fund's underlying strengths. Impatient informed trading is a significant source of alpha for funds trading high-PIN stocks, while liquidity provision is more important as a source of alpha for funds trading low-PIN stocks.

Informed Trading, Liquidity Provision, and Stock Selection by Mutual Funds

We show that a mutual fund's "stock selection skill" computed using the Daniel, Grinblatt, Titman and Wermers (1997) procedure can be decomposed into additional components that include impatient "informed trading" and "liquidity provision," thereby helping us understand how a fund creates value. We validate our method by verifying that liquidity provision is the dominant component of selection skill for Dimensional Fund Advisors U.S. Micro Cap fund, as observed by Keim (1999). Index funds lose on liquidity absorbing trades, since they pay the price impact on trades triggered by index rebalancing, inflows and redemptions. Consistent with the view that a mutual fund manager with superior stock selection ability is more likely to benefit from trading in stocks affected by information events, we find that funds trading such stocks exhibit superior performance that is more likely to persist. Further, such superior performance comes mostly from impatient informed trading. We also find that informed trading is more important for growth-oriented funds while liquidity provision is more important for younger funds with income orientation.

Extraction Method of Electrical Fire Material Evidence

AbstractIt is important for material evidence of identification in fire investigation, and the extraction method of material evidence has the most direct effect for the result of identification. How to extract the most valuable material evidence and find out the cause of the fire to provide a powerful evidence for fire, it is a skill for fire investigators must master. The efficiency of fire investigation will be greatly enhanced with the accuracy of evidence extraction, ensure that the reason is accurate for investigation

3-{[Bis(pyridin-2-ylmeth­yl)amino]­meth­yl}-2-hy­droxy-5-methyl­benz­aldehyde

In the title compound, C21H21N3O2, the pyridine rings and the benzene ring lie in a propeller arrangement around the central tertiary amine N atom. The dihedral angles formed by the benzene ring with the pyridine rings are 61.0 (3) and 49.6 (3)°, while the dihedral angle between the pyridine rings is 69.7 (3)°. The mol­ecular conformation is stabilized by intramolecular bifurcated O—H⋯N hydrogen bonds. In the crystal, inversion dimers are formed via pairs of C—H⋯N hydrogen bonds

Non-intact zona improves development of murine preimplantation embryos transfected by an adenovirus vector

The present study explored whether embryos could be transfected by the adenovirus-vector if the zona pellucida (ZP) was not completely removed. An adenovirus vector with green fluorescent protein (pAd-GFP) was used to transfect mouse non-intact zona zygotes (following partial removal of the ZP induced by pronase), zona-free and zona-intact embryos. Non-intact zona and zona-free embryos expressed GFP (confirmed with inverted fluorescence microscopy) after 48 h of culture. The transfection rate of non-intact zona group was up to 51% and the entire zona-free group was transfected. However, none of the zona-intact embryos was transfected. Regardless of whether non-intact zona embryos were transfected by pAd-GFP, their developmental rate (74.3 ± 2.4 and 69.2 ± 3.3% for non-transfected and transfected, respectively; mean ± SEM) was higher (P<0.05) than that of zona-free embryos without and with transfection (54.5 ± 4.3 and 46.7 ± 5.5%). Developmental potential of embryos was decreased for ZP-digestion (non-intact zona 71.8 ± 1.6%; zona-free 50.6 ± 2.2%, P<0.05) or pAd-GFP expression (non-transfected 64.4 ± 1.9%; transfected 56.0 ± 2.1%, P<0.05); therefore, ZP-digestion affected more intensely embryos development than pAd-GFP expression. In summary, non-intact zona murine embryos were readily transfected by the adenovirus-vector, and had much greater development potential than zona-free embryos. Although, the susceptibility of the ZP to digestion by pronase varied among embryos, on average, approximately 3.5 to 4.0 min of digestion resulted in partial removal of the ZP and promoted both transfection and satisfactory embryonic development. It is expected that this method could be used to increase the efficiency of generating transgenic animals.Keywords: Mouse, non-intact zona embryos, adenovirus vector with green fluorescent protein (pAd-GFP), embryos developmen

Relationship between low-density lipoprotein levels on admission and 1-year outcome in patients with acute ST-segment-elevation myocardial infarction

AbstractThis study assessed the relationship between low-density lipoprotein cholesterol (LDL-C) levels on admission and the incidence of major adverse cardiovascular events (MACE) in patients with acute ST-segment-elevation myocardial infarction (ASTEMI). Patients with ASTEMI who had a lipid profile tested within 24 hours of symptom onset were enrolled. They were stratified into high and low LDL-C groups according to whether their LDL-C was above (n = 501) or below (n = 575) the median level, respectively. The incidence of MACE, cardiovascular death, non-fatal MI, revascularization, and stroke was compared between the groups at 1 month, 6 months, and 1 year. Survival analysis and Cox proportional hazard analysis were performed. In-hospital use of beta blockers was better in the high than in the low LDL-C group (76.6% vs. 69.7%, p = 0.01). Statin use was significantly higher in the high than in the low LDL-C group during follow-up (86.8% vs. 80.0%, p = 0.003 at1 month; 71.6% vs. 62.4%, p = 0.002 at 6 months; 67.8% vs. 61.2%, p = 0.03 at 1 year). The incidence of MACE on follow-up at 1 month was higher in the low than in the high LDL-C group (12.0% vs. 8.1%, p = 0.04). At 1 year, survival was not significantly different between the groups. Cox proportional hazards analysis indicated that the incidence of MACE was significantly associated with hypertension, current smoking, high-density lipoprotein cholesterol (HDL-C), in-hospital use of beta blockers, and statin use on follow-up (p < 0.01). LDL-C levels on admission in patients with ASTEMI had no significant effect on the 6-month and 1-year incidence of MACE, but the incidence of MACE was significantly higher in the low LDL-C group at 1 month. It would be relevant to further investigate the HDL-C level on admission, in-hospital use of beta blockers, and statin use during follow-up in relation to MACE

GRB 200829A: External Shock Origin of the Very Early Prompt Emission?

Long-duration GRB~200829A was detected by Fermi-GBM and Swift-BAT/XRT, and then rapidly observed by other ground-based telescopes. It has a weak $\gamma$-ray emission in the very early phase and followed by a bright spiky $\gamma$-ray emission pulse. The radiation spectrum of the very early emission is best fitted by a power-law function with index $\sim -1.7$. However, the bright spiky $\gamma$-ray pulse, especially the time around the peak, exhibits a distinct two-component radiation spectra, i.e., Band function combined with a blackbody radiation spectrum. We infer the photospheric properties and reveal a medium magnetization at photospheric position by adopting the initial size of the outflow as $r_0=10^9$~cm. It implies that Band component in this pulse may be formed during the dissipation of magnetic field. The power-law radiation spectra found in the very early prompt emission may imply the external-shock origination of this phase. Then, we perform Markov Chain Monte Carlo method fitting on the light-curves of this burst, where the jet corresponding to the $\gamma$-ray pulses at around $20$~s is used to refresh the external-shock. It is shown that the light-curves of very early phase and X-ray afterglow after $40$~s, involving the X-ray bump at around $100$~s, can be well modelled in the external-shock scenario. For the obtained initial outflow, we estimate the minimum magnetization factor of the jet based on the fact that the photospheric emission of this jet is missed in the very early phase.Comment: Accepted for publication in Astrophysical Journa