500 câu trắc nghiệm Kinh tế lượng – 1C

SHORT ANSWER.

Write the word or phrase that best completes each statement or answers the question.
Identify the sample and population. Also, determine whether the sample is likely to be representative of the population.

6) An employee at the local ice cream parlor asks three customers if they like chocolate ice cream.
Sample: the 3 selected customers; population: all customers; not representative

Use critical thinking to address the key issue.

7) You plan to make a survey of 200 people. The plan is to talk to every 10th person coming out of the school library. Is there a problem with your plan?

People who don’t go to the library are excluded.

8) A national television channel posted the result of their web poll: “63 percent of Americans favor changing from gasoline to hydrogen fuel for cars.” The survey question had been available for three days and 50,000 viewers responded. Should we conclude that hydrogen-powered cars are favored by a majority of Americans? Explain.

This is not a random sample. The survey is based on voluntary, self-selected responses and therefore has serious potential for bias, because the result should not be generalized to all Americans.

9) A company accused of downsizing workers defended itself with the following statement: “Yes, we were forced to lay off 20% of our workforce last year, but this year we increased our workforce by 20%, and we therefore now have the same number of employees as before the layoff.” What is the flaw in this argument?

Answers will vary. Possible answer: This is a misleading use of percentages, as 20% of the reduced workforce is smaller than 20% of the original workforce. The company therefore did not hire as many new workers as it originally laid off. The size of the current workforce is therefore smaller than the size of the workforce before the layoffs.

MULTIPLE CHOICE.

Choose the one alternative that best completes the statement or answers the question.
Perform the requested conversions. Round decimals to the nearest thousandth and percents to the nearest tenth of a percent, if necessary.

10) Convert 1.2 to an equivalent fraction and percent.
○ \(1\frac{1}{{10}}\); 12%
● \(1\frac{1}{{5}}\); 120%
○ \(1\frac{1}{{5}}\); 12%
○ \(1\frac{1}{{10}}\); 120%

Solve the problem.

11) On a test of 80 items, Ariel got 68 correct. What percent were correct?
○ 117.647059%
○ 1.17647059%
○ 0.85%
● 85%

Is the study experimental or observational?

12) A quality control specialist compares the output from a machine with a new lubricant to the output of machines with the old lubricant.
● Experimental
○ Observational

13) A stock analyst selects a stock from a group of twenty for investment by choosing the stock with the greatest earnings per share reported for the last quarter.
○ Experimental
● Observational