ECON 2200 Chapter Notes - Chapter 12: Analysis Of Variance, Prediction Interval, Confidence Interval

65 views5 pages

sapphireminnow794

25 Mar 2017

School

Department

Course

Professor

For unlimited access to Textbook Notes, a Class+ subscription is required.

Document Summary

Bi-variate data when we study the relationship between two variables. Dependent variable the variable that is being predicted or estimated. Independent variable the variable that provides the basis for estimation: scaled on the y-axis, the predictor variable, scaled on the x-axis. Y-axis when x is zero: x - the sum of the values of the independent variable. Relationship between predicted values and the standard error of the. Estimate: y se will include the middle 68 percent of the observations, y 2se will include the middle 95 percent of the observations, y 3se will include virtually all the observations. Confidence interval for the mean of y: confidence interval reports the mean value of y for a given x. Prediction interval for an individual y: prediction interval reports the range of values of y for a particular value of x. Correlation analysis: a group of techniques to measure the strength of the association between two variables.

Related Questions

ECON 3050

Q24. The coefficient of determination (r²) is calculated as 0.49, then the correlation coefficient:

Cannot be determined without the data

Should be - 0.70 or 0.70

Should be 0.

Neither of the above

Q25. A regression line is used for all of the following except one. Which one is not a valid use of a regression line?

To estimate the average value of Y at a specified value of X.

To predict the value of Y for an individual, given that individual's X-value.

To estimate the change in Y for a one-unit change in X.

To determine if a change in X causes a change in Y.

Q26. Which choice is not an appropriate description of YË in a regression equation?

Estimated response

Predicted response

Estimated average response

Observed response

Q27. Which of the following is the best way to determine whether or not there is a statistically significant linear relationship between two quantitative variables?

Compute a regression line from a sample and see if the sample slope is 0.

Compute the correlation coefficient and see if it is greater than 0.5 or less than â0.5.

Conduct a test of the null hypothesis that the population slope is 0.

Conduct a test of the null hypothesis that the population intercept is 0.

Q28. There is no relationship between variables unless the data points lie in a straight line.

True

False

Q29. The sample regression analysis

Is the same as the population regression line

Is used to estimate the population regression line

Shows the true relation between dependent and independent variables

None of the above.

Q30. In regression, a dependent variable is sometimes called a predictor variable.

True

False

Q31. In a linear regression equation of the form y = a + bx, the intercept shows

The amount that y changes when x changes by one unit

The amount that x changes when y changes by one unit

The value of y when x is zero

The value of x when y is zero.

Q32. In a linear regression equation of y = a + bx, the slope b shows

Y / b

X / b

Y / X

X / Y

yellowturtle964

Econ 3050

7. When every member of the accessible population has an equal chance of being selected to participate in the study, the researcher is using:

a) Simple random sampling

b) Stratified random sampling

c) Convenience sampling

d) Purposive random sampling

8. A regression line has been found that has nearly all the points lying directly on the line, and only a few of them stray away from the line. Therefore, the standard error of the estimate is likely to be

Huge.

Small.

Undefined.

9. Correlation coefficient ranges from _______ to ____________.

a) - 1 to 0.

b) 0 to 1.

c) -1 to 1.

d) None of the above.

10. The correlation coefficient of determination is the:

a) Ratio of the explained variation to the total deviation.

b) Ratio of the unexplained deviation to the explained deviation.

c) Ratio of the unexplained deviation to the total variation.

d) Ratio of the explained variation to the total variation.

11. If the correlation coefficient r = 0.5 then the coefficient of determination is:

a) 0.10

b) 0.25

c) 1.00

d) 2.50

12. Which one of the following is NOT appropriate for studying the relationship between two quantitative variables?

Scatterplot

Bar chart

Correlation

Regression

13. In regression, an independent variable is sometimes called a response variable.

True

False

14. The simple linear regression equation can be written y = b₀ + b₁x. In the simple linear regression equation, the symbol y represents:

The average or predicted response

Estimated intercept

Estimated slope

Explanatory variable

mauvehyena239

Suppose that, instead of taking this test, you could either have worked and earned income or partied and had a pleasurable time. Your opportunity cost of taking the test is the

	a.	forgone working or partying, depending on which was your next best choice.
	b.	forgone work.
	c.	forgone working and partying.
	d.	test because you are taking it.

1 points

QUESTION 2

A trend is

	a.	a measure of closeness on a scatter diagram.
	b.	a general tendency for a variable to rise or fall.
	c.	the maximum value of a variable.
	d.	the difference between the maximum value of a variable and the minimum value of the variable.

1 points

QUESTION 3

A time-series graph measures

	a.	time on the y-axis and the variable or variables in which we are interested on the x-axis.
	b.	time on the x-axis and the variable or variables in which we are interested on the y-axis.
	c.	the value of one variable against the value of another variable.
	d.	the value of an economic variable for different groups in a population at a point in time.

1 points

QUESTION 4

Canada has nationalized health care, so that everyone, regardless of their ability to pay, has some access to health care. Based on this observation, Canada has decided that "everyone, regardless of their ability to pay" is the answer to what microeconomic question?

	a.	Why will we offer health care?
	b.	How will health care be produced?
	c.	For whom will health care be produced?
	d.	What type of health care will be produced and in what quantity?

1 points

QUESTION 5

As a shoe factory adds more workers, shoe production grows, reaches a maximum, and then shrinks. In a diagram that has the number of workers on the horizontal axis and the number of shoes on the vertical axis, the relationship between the number of workers and the number of shoes starts as ________ and then, after the maximum point, is ________.

	a.	positive; negative
	b.	negative; positive
	c.	linear; negative
	d.	positive; linear

1 points

QUESTION 6

Microeconomics includes the study of the

	a.	choices made by individuals and businesses.
	b.	recessions and inflation in the global economy.
	c.	aggregate effects on the national economy.
	d.	reasons why the government changes interest rates.

1 points

QUESTION 7

When Fresh Express Salads decides to mechanically pick all of its lettuce, it directly answers the ________ question.

	a.	when
	b.	for whom
	c.	how
	d.	what

1 points

QUESTION 8

Proponents of cuts in income tax rates argue that when income tax rates are cut, workers have an incentive to increase their work hours. This argument is based on the assumption that

	a.	the opportunity cost of working is negative.
	b.	the marginal cost of each additional work hour is not important to most workers.
	c.	workers are irrational.
	d.	workers make decisions based on the marginal benefit of each hour worked compared to the marginal cost of work.

1 points

QUESTION 9

A choice made by comparing all relevant alternatives systematically and incrementally is

	a.	an opportunity cost.
	b.	a benefit.
	c.	a sunk cost.
	d.	a choice on the margin.

1 points

QUESTION 10

A normative statement

i. can be tested as to whether it is true or false.

ii. is considered negative.

iii. depends on a person's values.

	a.	i, ii, and iii
	b.	iii only
	c.	i and iii
	d.	ii and iii

1 points

QUESTION 11

Normative statements

i. describe how the world is.

ii. describe how the world ought to be.

iii. depend on people's values and cannot be tested.

	a.	iii only.
	b.	i only.
	c.	ii and iii.
	d.	ii only.

1 points

QUESTION 12

In order to determine whether to major in economics, a rational individual compares the ________ of the decision.

	a.	positive benefits and normative costs
	b.	normative benefits and positive costs
	c.	marginal benefit and marginal cost
	d.	opportunity cost and the sunk cost

1 points

QUESTION 13

If x increases whenever y decreases, then x and y are

	a.	positively related.
	b.	negatively related.
	c.	not related.
	d.	related but whether positively or negatively related depends on whether the x variable or the y variable is plotted on the vertical axis.

1 points

QUESTION 14

Rational choice

	a.	is what you must give up get what you want.
	b.	is made by comparing different incentives.
	c.	making the choice.
	d.	provides the answer to only the "how" question.

1 points

QUESTION 15

Scarcity results from the fact that

	a.	choices made in self-interest rare not always in the social interest.
	b.	not all goals are desirable.
	c.	people's wants exceed the resources available to satisfy them
	d.	we cannot answer the major economic questions.

1 points

QUESTION 16

When Delta decides to quit flying to Lithuania, it directly answers the ________ question.

	a.	what
	b.	why
	c.	for whom
	d.	how

1 points

QUESTION 17

A normative statement

	a.	says what is currently believed about the way the world operates.
	b.	depends on someone's values.
	c.	cannot use the word "should."
	d.	must be tested to determine if it is correct.

1 points

QUESTION 18

Which of the following statements best describes the study of economics? Economics studies how

	a.	to organize production so that scarcity does not occur.
	b.	to create incentives so that scarcity does not exist.
	c.	firms make profits.
	d.	we make choices in the face of scarcity.

1 points

QUESTION 19

Which of the following best defines economics?

	a.	Economics teaches how to limit our wants.
	b.	Economics is concerned with prices and quantities of goods and services, both at the individual level and at the industry level.
	c.	Economics helps you earn as much money as possible.
	d.	Economics studies how to choose the best alternative when coping with scarcity.

1 points

QUESTION 20

In economics, cost is ________, and benefit is ________.

	a.	the amount of money that you pay for something; the amount of money that someone else is willing to pay you
	b.	what you are willing to pay on the margin; what the government pays you when you are unemployed or retired
	c.	what you must give up to get something; what you are willing to give up to get it
	d.	the amount of money that you pay on the margin; the amount of money that you receive on the margin

1 points

QUESTION 21

If Jessie studies economics for two hours instead of going to the movies with her friends, then

	a.	the opportunity cost of studying is the missed movie.
	b.	Jessie is ignoring a sunk cost
	c.	Jessie is not responding to any incentives.
	d.	Jesse definitely is making a rational choice.

1 points

QUESTION 22

Going skiing will cost Adam $80 a day. He also loses $40 per day in wages because he has to take time off from work. Adam still decides to go skiing.

	a.	The $80 price of skiing is a sunk cost and so did not affect Adam's decision.
	b.	He loses a total of $120 per day, so his decision is irrational.
	c.	His decision is rational if Adam's marginal benefit of spending a day skiing is greater than his marginal cost.
	d.	Adam's lost $40 per day in wages is a sunk cost and so did not affect his decision.

1 points

QUESTION 23

If a curve falls and then rises, it

	a.	has a maximum.
	b.	has a linear relationship.
	c.	has a minimum.
	d.	has a constant slope relationship.

1 points

QUESTION 24

In 2003, Michael Jordan decided to retire from professional basketball. Which of the following was an opportunity cost of his decision?

	a.	the avoidance of pain and injury from playing one more year
	b.	the time he could spend with his family while retired
	c.	the lost salary from playing one more year
	d.	the value of new employment opportunities that would await him

1 points

QUESTION 25

Which of the following statements is a normative statement?

	a.	Military spending as a percent of government spending decreased by 5 percent in the 1990s.
	b.	Every American household should have health care insurance coverage.
	c.	Welfare reform has decreased the amount the government spends on welfare.
	d.	The price of computers fell last year.

greencat417

ECON 2200 Chapter Notes - Chapter 12: Analysis Of Variance, Prediction Interval, Confidence Interval

Document Summary

Get access

Related Documents

ECON 2200 Chapter Notes - Chapter 13: Linear Regression, Dependent And Independent Variables, Explained Variation

S W 318- Midterm Exam Guide - Comprehensive Notes for the exam ( 14 pages long!)

S W 318 Lecture Notes - Lecture 12: Scatter Plot, Covariance, Ordinary Least Squares

Related Questions