Este documento presenta una introducción a la econometría. Explica que la econometría ayuda a combinar la teoría económica y los datos económicos para tomar mejores decisiones económicas. También describe los modelos econométricos básicos, incluido el modelo de regresión lineal simple, y los supuestos subyacentes a estos modelos. Finalmente, introduce conceptos clave como el término de error y los mínimos cuadrados ordinarios.
The document summarizes key concepts about freely falling objects and one-dimensional motion. It discusses that freely falling objects only experience the downward force of gravity. Galileo's experiment showing that objects of different masses fall at the same rate is mentioned. Equations of motion are provided for objects falling with initial velocities of zero, upward, or downward. Several example problems are worked through applying these equations to calculate time, displacement, velocity, and position at different times for balls thrown, dropped, or falling from heights.
Este documento presenta una introducción a la econometría. Explica que la econometría ayuda a combinar la teoría económica y los datos económicos para tomar mejores decisiones económicas. También describe los modelos econométricos básicos, incluido el modelo de regresión lineal simple, y los supuestos subyacentes a estos modelos. Finalmente, introduce conceptos clave como el término de error y los mínimos cuadrados ordinarios.
The document summarizes key concepts about freely falling objects and one-dimensional motion. It discusses that freely falling objects only experience the downward force of gravity. Galileo's experiment showing that objects of different masses fall at the same rate is mentioned. Equations of motion are provided for objects falling with initial velocities of zero, upward, or downward. Several example problems are worked through applying these equations to calculate time, displacement, velocity, and position at different times for balls thrown, dropped, or falling from heights.
1. The document discusses the basic principles of hypothesis testing, including stating the null and alternative hypotheses, selecting a significance level, choosing a test statistic, determining critical values, and making a decision to reject or fail to reject the null hypothesis.
2. It outlines the five steps of hypothesis testing: state hypotheses, select significance level, select test statistic, determine critical value, and make a decision.
3. Key terms discussed include type I and type II errors, significance levels, critical values, test statistics such as z and t, and the decision to reject or fail to reject the null hypothesis.
This document provides an overview of sequences and series. It defines what a sequence is, discusses concepts like convergence and divergence of sequences, and introduces common types of sequences like an = n and an = 1/n. It also presents rules for determining limits of sequences, such as the sum and product rules. Examples are provided to demonstrate applying these rules and the squeeze theorem for limits.
This document discusses one-tailed and two-tailed hypothesis tests. It explains that a one-tailed test looks for an increase or decrease in a parameter, while a two-tailed test looks for any change. If the claim uses words like "increased" or "decreased", it is a one-tailed test, while terms like "change" or "different" indicate a two-tailed test. A one-tailed test has a critical region in one tail, while a two-tailed test has critical regions in both tails. The example given is a one-tailed test comparing civil engineering and B.A. salaries, with the alternative hypothesis that engineering salaries are greater than B.A. salaries.
This document discusses one-tailed and two-tailed hypothesis tests. It explains that a one-tailed test looks for an increase or decrease in a parameter, while a two-tailed test looks for any change. If the claim uses words like "increased" or "decreased", it is a one-tailed test, while terms like "change" or "different" indicate a two-tailed test. A one-tailed test has a critical region in one tail, while a two-tailed test has critical regions in both tails. The example given is a one-tailed test comparing civil engineering and B.A. salaries, with the alternative hypothesis that engineering salaries are greater than B.A. salaries.
This document provides an overview of hypothesis testing and the steps involved. It discusses:
1) Defining the null and alternative hypotheses based on the research question. The null hypothesis represents "no difference" while the alternative hypothesis claims the null is false.
2) Calculating the test statistic, which is used to test the null hypothesis. For a one-sample z-test, this involves calculating the z-score when the population standard deviation is known.
3) Computing the p-value, which is the probability of observing a test statistic as extreme or more extreme than what was observed, assuming the null hypothesis is true. Small p-values provide strong evidence against the null.
4) Interpre
This document provides information about performing arithmetic operations with decimal numbers. It contains a glossary defining decimal-related terms, explanations of place value and how to write and compare decimals. The bulk of the document consists of examples and exercises for adding, subtracting, multiplying and dividing decimals. It concludes with decimal word problems and answers to the exercises. The overall purpose is to teach the essential skills for working with decimal numbers.
Este documento presenta ejercicios sobre sucesiones. Explica conceptos como términos, término general y tipos de sucesiones como aritméticas y geométricas. Incluye ejercicios para hallar términos, término general y criterios de formación de sucesiones recurrentes. También cubre límites de sucesiones, clasificando si convergen, divergen u oscilan.
This document provides an overview of hypothesis testing. It begins with an outline of the key topics to be covered, including the logic of hypothesis testing, types of errors, specific hypothesis tests, effect size, and statistical power. The body of the document then defines these concepts in more detail through examples and explanations. It discusses how to state hypotheses, set decision criteria, collect and analyze data, and make conclusions regarding whether to reject the null hypothesis. Factors that influence hypothesis tests like sample characteristics and test assumptions are also outlined.
This document discusses hypothesis testing and provides examples. It begins by explaining the typical four steps of hypothesis testing: determining the null and alternative hypotheses, collecting and summarizing data, calculating a test statistic and p-value, and making a decision. Two examples are then provided that demonstrate these steps for testing differences in means and proportions. The document concludes by noting how scientific journals present hypothesis tests, including reporting actual p-values rather than just decisions.
1) The document discusses first order partial differential equations, including their formation by eliminating arbitrary constants or functions from a given relation.
2) Methods for solving partial differential equations include direct integration, where simple equations can be solved by successive integrations with respect to the independent variables.
3) Standard types of solutions to partial differential equations are discussed, including complete, particular, and general solutions.
This document discusses various techniques for crystal structure analysis using diffraction of x-rays, electrons, and neutrons. It begins by introducing Bragg diffraction and references several textbooks on topics like x-ray diffraction, small-angle scattering, and protein crystallography. The document then covers the fundamentals of elastic and inelastic scattering, Bragg's law of diffraction, diffraction orders, and applications of techniques like powder diffraction, single-crystal diffraction, and thin film analysis.
The document discusses X-ray diffraction patterns of different crystal structures including simple cubic, body centered cubic, face centered cubic, and more complex structures. It provides the characteristic diffraction peak ratios for each structure type based on Miller indices and structure factor calculations. It also discusses how finite crystal size affects diffraction peak widths based on the Scherrer formula relationship between crystallite size and peak broadening.
1. The document discusses the basic principles of hypothesis testing, including stating the null and alternative hypotheses, selecting a significance level, choosing a test statistic, determining critical values, and making a decision to reject or fail to reject the null hypothesis.
2. It outlines the five steps of hypothesis testing: state hypotheses, select significance level, select test statistic, determine critical value, and make a decision.
3. Key terms discussed include type I and type II errors, significance levels, critical values, test statistics such as z and t, and the decision to reject or fail to reject the null hypothesis.
This document provides an overview of sequences and series. It defines what a sequence is, discusses concepts like convergence and divergence of sequences, and introduces common types of sequences like an = n and an = 1/n. It also presents rules for determining limits of sequences, such as the sum and product rules. Examples are provided to demonstrate applying these rules and the squeeze theorem for limits.
This document discusses one-tailed and two-tailed hypothesis tests. It explains that a one-tailed test looks for an increase or decrease in a parameter, while a two-tailed test looks for any change. If the claim uses words like "increased" or "decreased", it is a one-tailed test, while terms like "change" or "different" indicate a two-tailed test. A one-tailed test has a critical region in one tail, while a two-tailed test has critical regions in both tails. The example given is a one-tailed test comparing civil engineering and B.A. salaries, with the alternative hypothesis that engineering salaries are greater than B.A. salaries.
This document discusses one-tailed and two-tailed hypothesis tests. It explains that a one-tailed test looks for an increase or decrease in a parameter, while a two-tailed test looks for any change. If the claim uses words like "increased" or "decreased", it is a one-tailed test, while terms like "change" or "different" indicate a two-tailed test. A one-tailed test has a critical region in one tail, while a two-tailed test has critical regions in both tails. The example given is a one-tailed test comparing civil engineering and B.A. salaries, with the alternative hypothesis that engineering salaries are greater than B.A. salaries.
This document provides an overview of hypothesis testing and the steps involved. It discusses:
1) Defining the null and alternative hypotheses based on the research question. The null hypothesis represents "no difference" while the alternative hypothesis claims the null is false.
2) Calculating the test statistic, which is used to test the null hypothesis. For a one-sample z-test, this involves calculating the z-score when the population standard deviation is known.
3) Computing the p-value, which is the probability of observing a test statistic as extreme or more extreme than what was observed, assuming the null hypothesis is true. Small p-values provide strong evidence against the null.
4) Interpre
This document provides information about performing arithmetic operations with decimal numbers. It contains a glossary defining decimal-related terms, explanations of place value and how to write and compare decimals. The bulk of the document consists of examples and exercises for adding, subtracting, multiplying and dividing decimals. It concludes with decimal word problems and answers to the exercises. The overall purpose is to teach the essential skills for working with decimal numbers.
Este documento presenta ejercicios sobre sucesiones. Explica conceptos como términos, término general y tipos de sucesiones como aritméticas y geométricas. Incluye ejercicios para hallar términos, término general y criterios de formación de sucesiones recurrentes. También cubre límites de sucesiones, clasificando si convergen, divergen u oscilan.
This document provides an overview of hypothesis testing. It begins with an outline of the key topics to be covered, including the logic of hypothesis testing, types of errors, specific hypothesis tests, effect size, and statistical power. The body of the document then defines these concepts in more detail through examples and explanations. It discusses how to state hypotheses, set decision criteria, collect and analyze data, and make conclusions regarding whether to reject the null hypothesis. Factors that influence hypothesis tests like sample characteristics and test assumptions are also outlined.
This document discusses hypothesis testing and provides examples. It begins by explaining the typical four steps of hypothesis testing: determining the null and alternative hypotheses, collecting and summarizing data, calculating a test statistic and p-value, and making a decision. Two examples are then provided that demonstrate these steps for testing differences in means and proportions. The document concludes by noting how scientific journals present hypothesis tests, including reporting actual p-values rather than just decisions.
1) The document discusses first order partial differential equations, including their formation by eliminating arbitrary constants or functions from a given relation.
2) Methods for solving partial differential equations include direct integration, where simple equations can be solved by successive integrations with respect to the independent variables.
3) Standard types of solutions to partial differential equations are discussed, including complete, particular, and general solutions.
This document discusses various techniques for crystal structure analysis using diffraction of x-rays, electrons, and neutrons. It begins by introducing Bragg diffraction and references several textbooks on topics like x-ray diffraction, small-angle scattering, and protein crystallography. The document then covers the fundamentals of elastic and inelastic scattering, Bragg's law of diffraction, diffraction orders, and applications of techniques like powder diffraction, single-crystal diffraction, and thin film analysis.
The document discusses X-ray diffraction patterns of different crystal structures including simple cubic, body centered cubic, face centered cubic, and more complex structures. It provides the characteristic diffraction peak ratios for each structure type based on Miller indices and structure factor calculations. It also discusses how finite crystal size affects diffraction peak widths based on the Scherrer formula relationship between crystallite size and peak broadening.
1. Extrait du Journal en français facile du 7 avril 2023
Rédactrice : Katarina Lips
Faire tomber la pluie au Mexique
Activité 1 : Découvrir
Activité 2 : Écouter
1. Quel est le problème ?
Il n'y a pas assez d’eau.
2. Quelle solution propose le Mexique ?
provoquer la pluie
3. Dans quels pays cette méthode a-t-elle déjà été employée ?
en Chine
au Moyen-Orient
à Madagascar
4. Pour le chercheur Luis Ladino, « ce n’est pas une méthode miracle. »
5. Des scientifiques disent que cette méthode permet d’augmenter les précipitations de 25%.
6. Pour une validation scientifique, Luis Ladino dit qu’il faut reproduire ces résultats.
7. Quel est le risque cité par Ladino ?
Les conflits : les pays riches risquent de priver d'eau les autres pays.
Activité 3 : Vocabulaire
L’idée est d’injecter des sels dans les nuages pour faire pleuvoir, une méthode déjà employée en
Chine, au Moyen Orient ou encore à Madagascar. Mais attention, ce n’est pas une méthode miracle
contre la sécheresse, explique Louis Ladino, chercheur à l’Université nationale du Mexique : « Dans
certains cas, les expérimentations ont fonctionné. C’est vrai. Certains disent qu’elles permettent
d’augmenter parfois les précipitations de 25%. Mais en tant que scientifique, je les mets au défi de
me le prouver et de montrer qu’ils peuvent reproduire ces résultats. D’autre part, ça peut créer des
conflits, car ceux qui ont les moyens pourront diriger l’eau vers les endroits qui leur conviennent et en
priver ceux qui n’en ont pas les moyens. »