Magna Concursos

Foram encontradas 385 questões.

1072632 Ano: 2018
Disciplina: Estatística
Banca: ANPEC
Orgão: ANPEC
Provas:
Considere o seguinte modelo de regressão:
!$ Y_i = \beta_1x_i + u_i, i = 1, ..., n !$, em que !$ E[u_i|x_i] = 0 !$ e !$ Var[u_i|x_i] = σ^2 !$.
Considere três estimadores para !$ \beta_1 !$:
!$ b_1 = { \large \textstyle \sum_{i=1}^n (x_i - \bar x)(y_i - \bar y) \over \textstyle \sum_{i=1}^n(x_i - \bar x)^2} !$, !$ b_1^* = { \large \textstyle \sum_{i=1}^n x_iy_i \over \textstyle \sum_{i=1}^n x_i^2} !$, !$ b_1^{**} = { \large \textstyle \sum_{i=1}^n x_iy_i \over \textstyle \sum_{i=1}^n (x_i - \bar x)^2} !$, em que !$ \bar x = { \large 1 \over n} \textstyle \sum_{i=1}^n x_i !$.
Sobre esses estimadores, é correto afirmar:
Item 3 - !$ b_1^∗ !$ é um estimador consistente para !$ \beta_1 !$.
 

Provas

Questão presente nas seguintes provas
1072628 Ano: 2018
Disciplina: Estatística
Banca: ANPEC
Orgão: ANPEC
Provas:
Sejam X e Y variáveis aleatórias independentes. Cada uma dessas duas variáveis tem distribuição de Bernoulli com parâmetro p. Sendo W=max(X,Y), julgue a afirmativa abaixo:
Item 3 - E(W)= 2p.
 

Provas

Questão presente nas seguintes provas
1072614 Ano: 2018
Disciplina: Matemática
Banca: ANPEC
Orgão: ANPEC
Provas:
Suponha que temos dois conjuntos não vazios (A e B) de números reais. Sejam !$ f: A \rightarrow B !$ e !$ g: B \rightarrow A !$ duas funções que satisfazem !$ g (f(x)) = x !$ para todo !$ x ∈ A !$. Julgue a seguinte afirmativa:
Item 2 - Se !$ f !$ é sobrejetora, então !$ f(g(x)) = x !$ para todo !$ x ∈ B !$.
 

Provas

Questão presente nas seguintes provas
1072589 Ano: 2018
Disciplina: Matemática
Banca: ANPEC
Orgão: ANPEC
Provas:
Considere os seguintes limites fundamentais: !$ \textstyle \lim_{x \rightarrow 0} { \large senx \over x} = 1 !$, !$ \textstyle \lim_{x \rightarrow 0} { \large a^x - 1 \over x} = ln\ a !$, com !$ a !$ diferente de zero, e !$ \textstyle \lim_{x \rightarrow \infty}(1 + { \large 1 \over x})^x = 1 !$, com !$ e !$ sendo a base do logaritmo natural. A afirmativa que segue é certo ou errado?
Item 3 - !$ \textstyle \lim_{x \rightarrow 0} { \large 5^x - 2^x \over x} = ln2 - ln5. !$
 

Provas

Questão presente nas seguintes provas
1072575 Ano: 2018
Disciplina: Economia
Banca: ANPEC
Orgão: ANPEC
Provas:
Para uma economia periférica, como a brasileira, sempre foram muito relevantes suas relações com as condições internacionais de financiamento, geoeconômicas e geopolíticas. Sobre estas relações podemos afirmar:
Item 4 - A situação crítica de financiamento externo em 1982 e o temor do sistema financeiro privado em comprometer mais recursos com o Brasil exigiu, para a rolagem da dívida externa, que fossem mobilizados fundos de organismos oficiais, como o Banco de Compensações Internacionais (BIS), e mesmo do Governo Americano.
 

Provas

Questão presente nas seguintes provas
1071950 Ano: 2018
Disciplina: Matemática
Banca: ANPEC
Orgão: ANPEC
Provas:
Considere a matriz !$ A = \begin{pmatrix} cos (θ) & -sen (θ) \\ sen (θ) & cos (θ) \end{pmatrix} !$ como um operador linear em !$ \mathbb {R}^2 !$ e o produto interno entre !$ u = (u_1, u_2) !$ e !$ v = (v_1, v_2) !$ definido por !$ u ⋅ v = u_1v_1 + u_2v_2 !$. Classifique o item como certo ou errado:
Item 0 - A matriz A não corresponde a um operador ortogonal.
 

Provas

Questão presente nas seguintes provas
1071924 Ano: 2018
Disciplina: Matemática
Banca: ANPEC
Orgão: ANPEC
Provas:
Considere a matriz !$ A = \begin{pmatrix} cos (θ) & -sen (θ) \\ sen (θ) & cos (θ) \end{pmatrix} !$ como um operador linear em !$ \mathbb {R}^2 !$ e o produto interno entre !$ u = (u_1, u_2) !$ e !$ v = (v_1, v_2) !$ definido por !$ u ⋅ v = u_1v_1 + u_2v_2 !$. Classifique o item como certo ou errado:
Item 3 - Sejam !$ u !$ e !$ v !$ dois vetores com o mesmo comprimento (ou seja, !$ \parallel u \parallel = \parallel v \parallel !$). Então !$ u ⋅ Au = v ⋅ Av !$.
 

Provas

Questão presente nas seguintes provas
1071912 Ano: 2018
Disciplina: Economia
Banca: ANPEC
Orgão: ANPEC
Provas:
O período entre 1968 e 1973 é conhecido como “milagre econômico”. Sobre este período pode-se afirmar:
Item 1 - O I Plano Nacional de Desenvolvimento (I PND), para o período 1971-1974, propunha a aceleração do crescimento do PIB, para o que deveria se expandir o crédito em instituições federais, como o Banco do Brasil, o BNDE e a Caixa Econômica Federal.
 

Provas

Questão presente nas seguintes provas
1071892 Ano: 2018
Disciplina: Inglês (Língua Inglesa)
Banca: ANPEC
Orgão: ANPEC
Provas:
Determine whether each statement is right or wrong.
Russia and NATO
Outgunned
The Atlantic alliance faces superior conventional forces near Russia’s borders
The Economist print edition | Europe
March 10th -16th 2018 |
BOASTING about nuclear weapons is something Vladimir Putin clearly enjoys. In his annual stateof- the-nation speech on March 1st, he listed five new weapons. Russia’s president gave pride of place to the development of a nuclear-powered cruise missile with, in effect, unlimited range, which was guaranteed to thwart America’s missile defences (see Science). He got the headlines he wanted, though there is nothing new about Russia being able to devastate America with nuclear weapons, nor anything likely to change on that front. What should concern Europe more than Mr Putin’s nuclear sabre-rattling are the formidable conventional forces that Russia is steadily building up, particularly in the Baltic region.
On most measures, NATO appears comfortably ahead of Russia. Between them, America and its European NATO allies spent $871bn on defence in 2015, compared with Russia’s $52bn. But as a recent report by the RAND Corporation, a think-tank, argues, the reality on the ground is rather different. It finds that Russia would now enjoy significant local superiority in any confrontation with NATO close to its own border. NATO’s latent strengths, once they were brought to bear, would be too much for Russia to cope with. But in the early stages of a conflict, for at least the first month and possibly for a good deal longer, the alliance would find itself outnumbered, outranged and outgunned.
Since Russia’s invasion of eastern Ukraine in 2014, NATO has bolstered its forces in the Baltic region with what it calls its “enhanced forward presence”. By last summer, the alliance had a total of 4,530 troops near the border with Russia in four battle-groups led by Germany (in Lithuania), Britain (in Estonia), Canada (in Latvia) and the United States (in Poland). But, in accord with the 1997 NATO-Russia Founding Act, an anachronistic agreement that reflected a more optimistic time, the soldiers are not permanently based, but constantly rotate.
NATO has also beefed up its “very high readiness joint task-force” of about 5,000 more troops who can be deployed within a week. But it admits that neither force is more than a tripwire to convince Russia that any attack on them would be seen as an attack on the alliance as a whole.
Over the past decade, Western forces and their Russian counterparts have diverged in terms of capability. NATO members adjusted for counter-insurgency operations in places such as Afghanistan by restructuring with light expeditionary forces. Russia concentrated on rebuilding forces with the mobility and firepower to wage high-intensity warfare against a peer adversary. As part of a comprehensive effort at military reform following a disjointed performance in the war against Georgia in 2008, Russia has professionalised its forces (largely relegating conscripts to a second echelon), equipped them with modern heavy weapons, and honed them with frequent large-scale exercises and combat experience in Ukraine and Syria.
What worries NATO commanders, such as General Sir Nicholas Carter, chief of Britain’s general staff, and his American opposite number, General Mark Milley, is the sheer amount of combat power Russia can concentrate at very short notice in the Baltic region. RAND found that in main battle tanks, Russia would outnumber NATO by 5.9 to 1; in infantry fighting vehicles by 4.6 to 1; in rocket artillery by 270 to none. And while NATO would enjoy a substantial advantage in combat aircraft, their effectiveness would be greatly reduced when faced with the world’s most powerful integrated theatre air defences.
Russia’s edge over NATO, says Ben Barry of the International Institute for Strategic Studies, is increased by its ability to use its internal lines to reinforce at speed. By contrast, NATO has neglected to preserve its cold-war military-transport infrastructure. Bridges cannot take the weight of tanks, and rail systems are not designed for trucks carrying heavy armour.
There is plenty that NATO could do to enhance conventional deterrence. It could permanently station forces in the Baltic region with more hitting power; it could hold regular large-scale short-notice exercises; it could invest in strengthening its internal lines; individual member countries could do more to meet their spending obligations and use the money to restructure their ground forces for high-intensity conflict.
Whether NATO is capable of such focus is debatable. Its southern members worry more about refugee flows; France is fighting an insurgency in the Sahel; Germany’s new coalition agreement relegated the (wretched) state of its armed forces to page 156 of a 177-page document. Mr Putin’s priorities are very different.
We understand from the text that:
Item 0 - Mr. Putin is extremely modest about Russia's nuclear weapons;
 

Provas

Questão presente nas seguintes provas
1071814 Ano: 2018
Disciplina: Economia
Banca: ANPEC
Orgão: ANPEC
Provas:
Sobre as questões relacionadas ao mundo do trabalho no Brasil, pode-se afirmar:
Item 3 - Foram estabelecidas pelo Governo Getúlio Vargas instituições de formação técnica para o mercado de trabalho, seja na indústria, por meio do Serviço Nacional de Aprendizagem Industrial (SENAI), seja no Comércio, por meio do Serviço Nacional de Aprendizagem Comercial (SENAC).
 

Provas

Questão presente nas seguintes provas