Achieve Quiz 1 (ch 0,1,2)

Most data analysis begins by doing what? a. graphing the data and constructing numerical summaries b. conducting statistical tests and drawing conclusions c. none of the choices are correct d. writing surveys and collecting data

a. graphing the data and constructing numerical summaries

A sample survey is an example of what kind of study? a) neither an experiment nor an observational study b) an observational study c) an experiment

b) an observational study

A teacher gave a 25‑question multiple‑choice test. After scoring the tests, she computed a mean and standard deviation of the scores. The standard deviation was 0. Based on this information: a. the teacher must have made a mistake in her computations. b. about half of the scores were above the mean. c. all of the students had the same score.

c. all of the students had the same score.

A group of four friends has a median age of \\( 22\! \\) . Three of the friends are ages \\( 20\! \\) , \\( 18\! \\) , and \\( 24\! \\) . The age of the fourth friend must be: a) \\( 22\! \\) . b) None of these choices are correct; we can't tell from the information provided. c) \\( 18 \\) or younger. d) \\( 24 \\) or older.

d) \\( 24 \\) or older.

A survey of radio stations was conducted following the attacks on the World Trade Center in \\( 2001\! \\) . One of the variables recorded was the region the station was located in (east, center, or west). The variable "region" is: a) quantitative, because region is a number. b) quantitative, because region is not a number. c) categorical, because region is a number. d) categorical, because region is a not a number.

d) categorical, because region is a not a number.

Consider the presented time plot of the price of a commodity, in dollars, for each month of a 60‑month period. Which of the given is true about the time plot? The price appears to be cyclical; that is, it shows regular up and down patterns, as the months increase. There is not an overall trend for prices, that is, prices do not change overall as the months increase.

*couldn't put a picture*

In my friend's coin purse, I found 12 pennies. The ages, in years, of the pennies obtained by subtracting the year stamped on the coin from 2016 follow. 22, 14, 8, 1, 9, 0, 31, 2, 13, 3, 11, 10 Rounding to the nearest tenth, the mean and median of this distribution (in years) are: 11.3 and 9.5. 10.3 and 9.5. 9.5 and 10.3. 10.3 and 10.5.

10.3 and 9.5

New England Patriots quarterback Tom Brady's total passing yards per year, from his rookie season in 2000 until 2016, are shown in the given time plot. Source: http://www.nfl.com/player/tombrady/2504211/careerstats Which years represent outliers? 2007 and 2009 2000 and 2008 2000 and 2016 2008 and 2011

2000-2008

A sample was taken of the salaries of four employees from a large company. The following are their salaries, in thousands of dollars, for this year. 33 31 24 36 The variance of their salaries is: 26 31 5.1

26

Which of the following sets of four numbers has the smallest standard deviation? \\( 7, 8, 9, 10 \\) \\( 0, 1, 2, 3 \\) \\( 5, 5, 5, 6 \\) \\( 0, 0, 10, 10 \\)

\\( 5, 5, 5, 6 \\)

Data for the daily values of the Dow Jones Industrial stock market average, for the last part of 2005 and the first part of 2006, are displayed in the given time plot This plot shows: a trend. cycles. both a trend and cycles.

a trend

Consider the timeplot of the price of a commodity, in dollars, for each month of a 60‑month period. Which of the following is true about the time plot? The frequency graph shows Month on x-axis and Price on y-axis. It represents that the price is fluctuating. X-axis measures months from 12 to 60 with an interval of 12 months. There is a gap between the origin of the axis to the first point representing 12 months. This gap measures month 1 to 12. Y-axis measures price from 1 to 7 dollars with an interval of 2. The price of the commodity in month 1 is approximately 1 dollar and at month 60 is approximately 7 dollars. The lowest price appears roughly midway between month 1 and 12. The price shows regular up and down patterns as the months increase. a) The lowest price of the commodity occurred around month 6. b) Both choices are correct. c) The increase in the price of the commodity from month 1 to month 60 is $7.

a) The lowest price of the commodity occurred around month 6.

Which of the statements is true? a) We can never be 100% confident in the conclusions of a statistical study. b) Errors and lurking variables are the only sources of variation in data. c) A good statistical study will account for all sources of variability, so that we can be 100% confident in our conclusions.

a) We can never be 100% confident in the conclusions of a statistical study.

When ordering vinyl replacement windows, the following variables are specified for each window. Which of these variables is quantitative? a) area of the window opening, in square inches b) window style—double-hung, casement, or awning c) window style—single pane or double pane

a) area of the window opening, in square inches

Statistics can be thought of as involving four steps: 1. draw conclusions 2. plan the specific statistical work needed 3. state the problem 4. solve the problem by making the necessary graphs and calculations In what order should these steps be performed? a) 2, 3, 4, 1 b) 3, 2, 4, 1 c) 3, 4, 2, 1 d) These are not the four steps of statistics.

b) 3, 2, 4, 1 - state the problem - plan the specific statistical work needed - solve the problem by making the necessary graphs and calculations - draw conclusions

Opinion polls, such as those performed by Gallup, can best be described as what type of data collection method? a) an observational study b) a sample survey c) an experiment

b) a sample survey

If we want to study the reasons that students binge drink, we should: a) randomly assign students to a group that is allowed to binge drink. b) do a survey of students, asking about binge drinking and their reasons for doing so. c) None of the answer options is correct. d) observe which students binge drink and which students do not, and see if we can identify any differences.

b) do a survey of students, asking about binge drinking and their reasons for doing so.

There are three children in a room, ages \\( 3\! \\) , \\( 4\! \\) , and \\( 5\! \\) . If another \\( 4\! \\) -year-old enters the room: a) the mean age will stay the same, but the variance will increase. b) the mean age will stay the same, but the variance will decrease. c) the mean age and variance will stay the same. d) the mean age and variance will increase.

b) the mean age will stay the same, but the variance will decrease.

The bars on a histogram: a) should be drawn with gaps between them to separate the quantities being compared. b) touch one another unless there are no values for that class. c) can be drawn to touch one another or not; it makes no difference.

b) touch one another unless there are no values for that class.

A company has three divisions and three conference rooms for meetings. To keep track of the use of their facilities, for each meeting the company records the name of the division holding the meeting, the conference room used, and the length of time of the meeting. Which of the variables is quantitative? a. the conference room used b. the length of time of the meeting c. All of the answer options are correct. d. the name of the division holding the meeting

b. the length of time of the meeting

The purpose of studying statistics is to: a) describe uncertainty in data and conclusions drawn from data. b) seek patterns underlying variation in data. c) All of the answer options are correct. d) gain insight and learn from data.

c) All of the answer options are correct.

Does the value of the standard deviation depend on the value of the mean? a. No, because the center of a distribution and the spread are not related. b. Yes, because if the mean gets larger, the standard deviation will also get larger. c. Yes, because the mean must be known in order to calculate the standard deviation.

c. Yes, because the mean must be known in order to calculate the standard deviation.

Which of the following statements is true about learning from data? a) It does not matter where you get your data, as long as there are enough of them. b) All of the answer options are correct. c) It is possible to reach conclusions without knowing how the data were collected. d) It is important to know the context within which the problem is to be solved.

d) It is important to know the context within which the problem is to be solved.