background preloader

Probability and statistics

Probability and statistics
Related:  askurBasics of Numbers, Reporting & Learning

Calcul des probabilités La probabilité d'un événement est le pourcentage de "chances" que cet évenement se réalise. Par exemple si un événement a 25 chances sur 100 de se réaliser, on dira que sa probabilité est de 25% (ou 0,25 ou 1/4) Une probabilité est donc toujours comprise entre 0 et 1 (ou entre 0% et 100%) On note en général un événement sous la forme d'une lettre majuscule : A, B... On notera P(A) la probabilité que l'événement A se réalise. On notera "non A" l'événement contraire de A, c'est à dire celui qui se réalise quand A ne se réalise pas et inversement. Dans l'exemple, la probabilité de "non A" (qui est la probabilité que A ne se réalise pas) vaut 0,75 = 1 - 0,25. On aura toujours P(A) + P(non A) = 1, en effet A et nonA sont des événements qu'on qualifie d'incompatibles (car ils ne peuvent se réaliser simultanément); de plus l'un des deux doit forcément se réaliser. On en déduit : P(non A) = 1 - P(A) A partir de deux événements A et B, on peut définir deux nouveaux événements : "A ou B" "A et B"

Einn stærsti vísindastyrkur sem ratað hefur til Íslands ©Kristinn Ingvarsson(fengin af www.landspitali.is) Rannsóknarhópur Sigurðar Yngva Kristinssonar hlaut á dögunum rannsóknarstyrk uppá 2,4 milljónir bandaríkjadala. Þessi upphæð samsvarar 300 milljónum íslenskra króna, en styrkinn hlaut hópurinn frá alþjóðlegum samskeppnissjóð sem staðsettur er í Kaliforníu og heitir International Myeloma Foundation. Verkefnið sem styrknum er ætlað að fjármagna snýst um að skilgreina svokallaða einstofna góðkynja mótefnahækkun (MGUS) en það er forstig krabbameins sem kallast mergæxli. Rannsóknin fer þannig fram að 140.000 einstaklingum á Íslandi er boðið uppá skimun á MGUS. Með þessu móti ætlar rannsóknarhópurinn að svara mikilvægum spurningum eins og hvort skimun fyrir MGUS sé hagkvæm og æskileg, hvaða áhrif það hefur á lífsgæði einstaklinga að greinast með MGUS og hvort hægt sé að meðhöndla mergæxlin á forstigi, en slík meðferð tíðkast ekki eins og staðan er í dag.

Operational definition (What is it? When is it used?) | Data collection tools | Quality Advisor What is it? An operational definition, when applied to data collection, is a clear, concise detailed definition of a measure. The need for operational definitions is fundamental when collecting all types of data. It is particularly important when a decision is being made about whether something is correct or incorrect, or when a visual check is being made where there is room for confusion. For example, data collected will be erroneous if those completing the checks have different views of what constitutes a fault at the end of a glass panel production line. Defective glass panels may be passed and good glass panels may be rejected. When collecting data, it is essential that everyone in the system has the same understanding and collects data in the same way. When is it used? Any time data is being collected, it is necessary to define how to collect the data. Free monthly quality tips Subscribe to our free monthly newsletter, Quality eLine.

Lois de Poisson (des petites probabilités) 4.2. Lois de Poisson. Les lois de Poisson sont très utiles dans l’étude de la survenance dans le temps d’événements homogènes, contrairement aux lois Binomiales Négatives qui sont plus appropriées pour les événements hétérogènes. Définition 1. P(X=k)=\frac{\lambda^k}{k!} Nous notons {\cal L}(X)={\cal P}(\lambda). Modélisation. Propriété 1. 1). P(Y(\lbrack t, t+\Delta T \rbrack)=1)=\lambda\Delta t=1-P(Y(\lbrack t, t+\Delta T \rbrack)=0). C’est-à-dire qu’à chaque instant nous n’observons qu’une seule ou aucune réalisation de l’événement. 2). 3). {\cal L}(Y(\lbrack a, b \rbrack))={\cal L}(Y(\lbrack 0, b-a \rbrack). C’est-à-dire que le nombre de réalisations de l’événement ne dépend pas de l’instant du début de l’observation mais de la durée de celle-ci. Si les trois conditions précédentes sont satisfaites, alors : {\cal L}(Y(\lbrack 0, t \rbrack))={\cal P}(\lambda t),\qquad \forall t\in {\mathbb R}_+. Remarque 1. Remarque 2. e^a=\sum_{k=0}^{\infty}\frac{a^k}{k!} Calculs avec R. Remarque 3.

Myndir Basic Statistics: About Incidence, Prevalence, Morbidity, and Mortality - Statistics Teaching Tools - New York State Department of Health What is incidence? Incidence is a measure of disease that allows us to determine a person's probability of being diagnosed with a disease during a given period of time. Therefore, incidence is the number of newly diagnosed cases of a disease. An incidence rate is the number of new cases of a disease divided by the number of persons at risk for the disease. If, over the course of one year, five women are diagnosed with breast cancer, out of a total female study population of 200 (who do not have breast cancer at the beginning of the study period), then we would say the incidence of breast cancer in this population was 0.025. What is prevalence? Prevalence is a measure of disease that allows us to determine a person's likelihood of having a disease. What is morbidity? Morbidity is another term for illness. What is mortality? Mortality is another term for death.

Mooc Gestion de projet Rappel MOOC : Massive Open Online Course : formation ouverte et à distance ; les participants, enseignants et apprenants, sont du monde entier, ils travaillent et communiquent par internet ; supports variés : vidéos, quizz interactifs, forums de discussion, session de réponses aux questions posées aux prof/animateurs etc… Après avoir suivi ITyPA (dont les animateurs ont construit une formidable capitalisation), j’adhère au premier MOOC certificatif français gestion de projet La lettre n°1 du MOOC Gestion de Projet Retour haut de pageLa lettre n°1, outre le point général sur les inscriptionsles dates de cours (18 Mars au 15 Avril 2013 complète les 2 niveaux de difficulté déjà évoqués pour les certificats basiques et avancés avec l’ouverture d’une certification supplémentaire pour les plus motivés à la fin du cours : un certificat par équipes-projets, indépendant du cours mais mettant en pratique ce que nous y aurons sur la gestion La lettre n°2 du MOOC Gestion de Projet Retour haut de page

The mindfulness conspiracy | Life and style Mindfulness has gone mainstream, with celebrity endorsement from Oprah Winfrey and Goldie Hawn. Meditation coaches, monks and neuroscientists went to Davos to impart the finer points to CEOs attending the World Economic Forum. The founders of the mindfulness movement have grown evangelical. So, what exactly is this magic panacea? But anything that offers success in our unjust society without trying to change it is not revolutionary – it just helps people cope. There are certainly worthy dimensions to mindfulness practice. What remains is a tool of self-discipline, disguised as self-help. But none of this means that mindfulness ought to be banned, or that anyone who finds it useful is deluded. The fundamental message of the mindfulness movement is that the underlying cause of dissatisfaction and distress is in our heads. Mindfulness advocates, perhaps unwittingly, are providing support for the status quo. Mindfulness is said to be a $4bn industry.

Related: