Un portrait de l?investisseur individuel français

L'objet de cet article est de mettre en lumière à partir de données empiriques les caractéristiques de l'investisseur individuel français. Un échantillon de 92 603 porteurs de valeurs mobilières réalisant des opérations entre 1999 et 2006 est étudié. Des statistiques descriptives sur les variables démographiques, les comptes détenus, les transactions réalisées ainsi que les portefeuilles sont présentées. Nos principaux résultats peuvent être résumés ainsi : le porteur français est en moyenne un homme âgé de 42 ans et habite l'Ile de France. Lorsqu'il détient un compte PEA, il le clôture avant la date à laquelle l'avantage fiscal est activé (5 ans). De nombreux investisseurs réalisent moins de 6 opérations entre 1999 et 2006 et seulement 1,62% des porteurs font plus de 1000 opérations sur cette période. Même si plus de la moitié des investisseurs diversifient leurs portefeuilles à l'international, 90% des transactions portent sur des titres français. Le nombre d'actions ordinaires différentes détenues augmente de 2005 à 2006, suggérant que les investisseurs diversifient de plus en plus leurs portefeuilles. Enfin, plus de 30% des porteurs ont investi entre 1999 et 2006 moins de 10 000 euros sur leur portefeuille.Comportement d'investissement, investisseur individuel.

Trading activity and Overconfidence: First Evidence from a large European Database

We investigate the presence of overconfidence for 43 958 individual investors using a large brokerage account database between 1999 and 2006. We employ three methodologies to gauge overconfidence and our main results show that independently of the methodology considered, individual investors are subject to overconfidence and consequently trade too frequently. Securities investors are buying are systematically underperforming those they are selling on follow-up periods; investors are clearly not making profitable trades.

Are French Individual Investors reluctant to realize their losses?

We analyze the presence of the disposition effect for 90 244 French individual investors based on a large brokerage account database between 1999 and 2006. Main results show that a) French investors demonstrate a strong preference for realizing their winning stocks rather than their losing ones (disposition effect).b) the behavioral bias is not eliminated for sophisticated individual investors (higher trading activity or international diversification) c) more originally, based on French account specificities, we demonstrate that the change of “fiscal account type” does not imply a change in investors’ behavior (at an individual level of the disposition effect).

Oral estradiol/micronized progesterone may be associated with lower risk of venous thromboembolism compared with conjugated equine estrogens/medroxyprogesterone acetate in real-world practice.

OBJECTIVES The Women's Health Initiative study reported an increased risk of venous thromboembolism among menopausal women treated with conjugated equine estrogens/medroxyprogesterone acetate (CEE/MPA) versus placebo. Newer hormone therapies may have a lower venous thromboembolism risk. The study compared the risk of venous thromboembolism between women treated with the combined oral product 17β-estradiol/micronized progesterone (E2/P4) and those treated with oral CEE/MPA regimens. STUDY DESIGN In a retrospective longitudinal study using real-world claims data from April 2019 to June 2021, women aged 40 years or more treated with oral E2/P4 or oral CEE/MPA who did not have a venous thromboembolism diagnosis before first dispensing claim of CEE/MPA or E2/P4 identified on or after May 1st 2019 (index date) were observed for 6 months or more after the index date. Oral E2/P4 and oral CEE/MPA had been prescribed by the treating physician in real-world practice and were observed through pharmacy dispensing records. MAIN OUTCOME MEASURES Venous thromboembolism risk was compared between women receiving oral E2/P4 versus oral CEE/MPA. RESULTS The study included 36,061 women treated with oral E2/P4 or oral CEE/MPA. In the analyses weighted by the inverse probability of treatment for control of potential confounding factors, the incidence of venous thromboembolism was significantly lower for oral E2/P4 compared with oral CEE/MPA (37/10,000 women-years for oral E2/P4 vs 53/10,000 women-years for oral CEE/MPA; incidence rate ratio 0.70, 95 % confidence interval: 0.53-0.92). CONCLUSIONS Real-world evidence suggests that the risk of venous thromboembolism is significantly lower among women treated with oral E2/P4 compared with oral CEE/MPA

Stock market investors' use of stop losses and the disposition effect

The disposition effect is an investment bias where investors hold stocks at a loss longer than stocks at a gain. This bias is associated with poorer investment performance and exhibited to a greater extent by investors with less experience and less sophistication. A method of managing susceptibility to the bias is through use of stop losses. Using the trading records of UK stock market individual investors from 2006 to 2009, this paper shows that stop losses used as part of investment decisions are an effective tool for inoculating against the disposition effect. We also show that investors who use stop losses have less experience and that, when not using stop losses, these investors are more reluctant to realise losses than other investors

Role of PKG-L-type calcium channels in the antinociceptive effect of intrathecal sildenafil

Sildenafil increases the cyclic guanosine monophosphate (cGMP) by inhibition of a phosphodiesterase 5, thereby leading to an antinociceptive effect. The increased cGMP may exert the effect on an L-type calcium channel through the activation of protein kinase G (PKG). The purpose of this study was to examine the possible involvement of a PKG-L-type calcium channel on the effect of sildenafil at the spinal level. Catheters were inserted into the intrathecal space of male SD rats. Pain was induced by applying 50 µL of a 5% formalin solution to the hindpaw. The sildenafil-induced effect was examined after an intrathecal pretreatment of a PKG inhibitor (KT 5823), or a L-type calcium channel activator (FPL 64176). Intrathecal sildenafil produced an antinociceptive effect during phase 1 (0~10 min interval) and phase 2 (10~60 min interval) in the formalin test. Intrathecal KT 5823 and FPL 64176 attenuated the antinociceptive effect of sildenafil during both phases. Sildenafil is effective against both acute pain and the facilitated pain state at the spinal level. In addition, the inhibition of an L-type calcium channel by activation of the PKG may contribute to the antinocieptive mechanism of sildenafil in the spinal cord

cAMP-Signalling Regulates Gametocyte-Infected Erythrocyte Deformability Required for Malaria Parasite Transmission.

Blocking Plasmodium falciparum transmission to mosquitoes has been designated a strategic objective in the global agenda of malaria elimination. Transmission is ensured by gametocyte-infected erythrocytes (GIE) that sequester in the bone marrow and at maturation are released into peripheral blood from where they are taken up during a mosquito blood meal. Release into the blood circulation is accompanied by an increase in GIE deformability that allows them to pass through the spleen. Here, we used a microsphere matrix to mimic splenic filtration and investigated the role of cAMP-signalling in regulating GIE deformability. We demonstrated that mature GIE deformability is dependent on reduced cAMP-signalling and on increased phosphodiesterase expression in stage V gametocytes, and that parasite cAMP-dependent kinase activity contributes to the stiffness of immature gametocytes. Importantly, pharmacological agents that raise cAMP levels in transmissible stage V gametocytes render them less deformable and hence less likely to circulate through the spleen. Therefore, phosphodiesterase inhibitors that raise cAMP levels in P. falciparum infected erythrocytes, such as sildenafil, represent new candidate drugs to block transmission of malaria parasites