Stats Test 1
A scatter diagram can be used to do which of the following?
Analyze the relationship between two variables
Which of the following is an example of graphs used to describe data?
Histograms and bar charts
When data are organized into levels, the highest data level is:
Ratio level data
A histogram is used to display which of the following characteristics for a quantitative variable?
The shape of the distribution, the spread in the data, and the approximate center of the data
Which of the following is a reason for constructing a joint frequency distribution?
To help analyze the relationship between the two variables
Statistics is a discipline that involves tools and techniques used to describe data and draw conclusions.
True
When customers return a product to a store and the store asks the customer to indicate the reason that the merchandise was returned, the resulting data are quantitative since multiple people will be providing the data
false
When the park ranger at Yellowstone National Park reports the average length of time that visitors spend in the park, he is using:
numerical measures
In drawing a box and whisker plot the upper limit length of the whiskers is 1.5(Q3-Q1).
true
A study was recently done in which the brand preference for breakfast cereal was analyzed against the gender of the shopper. The study consisted of 200 male shoppers and 300 female shoppers. Three different cereal brands were considered: A, B, and C. A total of 250 female shoppers preferred brand A, 25 female shoppers preferred brand C. A total of 100 shoppers preferred brand B. The number of male shoppers that preferred brand B was:
75
Descriptive statistics allow a decision maker to reach a conclusion about a population based on a subset from the population.
False
When choosing class boundaries for a frequency distribution, classes such as 60-70, 70-80, 80-90 would be acceptable.
False
The human resources department at a major high tech company recently conducted an employee satisfaction survey of 100 of its 3,000 employees. Data were collected on such variables as age, gender, marital status, current salary, level of overall satisfaction on a scale from 1 to 5, number of years with the company, and job title. Which of the variables would be classified as nominal level data?
Gender, marital status, and job title
The human resources department at a major high tech company recently conducted an employee satisfaction survey of 100 of its 3,000 employees. Data were collected on such variables as age, gender, marital status, current salary, level of overall satisfaction on a scale from 1 to 5, number of years with the company, and job title. Which of the variables would be considered to be qualitative data?
Gender, marital status, job satisfaction, and job title
The company that makes a new weight loss pill claims that people who use this pill according to instructions will lose an average of 20 pounds during a four-month period. They say the claim is based on a study of 300 people. Which of the following statistical methods was most likely used to arrive at the company's conclusion?
Hypothesis testing
When a marketing manager surveys a few of the customers for the purpose of drawing a
Inferential statistics
Which of the following questions CANNOT be answered using a scatter diagram?
Is there a causal relationship between the 2 variables?
Which of the following is NOT true of a bar chart?
It is used for numerical data
A political poll that is used to indicate the percentage of voters who will vote for a particular candidate makes use of which of the following?
Numerical Analysis and Estimation
Which of the following is not considered desirable when constructing a frequency distribution for continuous data?
Open- ended classes
Which of the following types of questions provide the respondent with the greatest choice in responding to a question?
Open-end questions
When a survey uses the responses strongly disagree, disagree, neutral, agree, strongly agree, this is an example of
Ordinal Data
The city counsel has just voted to pass the city's budget for next year. If you were writing a report describing the budget so the citizens could understand how the total tax dollars will be spent, which of the following graphs might be most appropriate?
Pie chart
The human resources department at a major high tech company recently conducted an employee satisfaction survey of 100 of its 3,000 employees. Data were collected on such variables as age, gender, marital status, current salary, level of overall satisfaction on a scale from 1 to 5, number of years with the company, and job title. Considering the age variable where employees were asked to list their age at their last birthday, which of the following best describes the level of data measurement for that variable?
Ratio level
An Internet service provider wants to determine its level of customer satisfaction. The best data collection method to obtain the results most quickly is:
Telephone survey
One of the advantages that a stem and leaf diagram has over a histogram is:
The detail of the data is preserved
Recently a survey was conducted in which customers of a large insurance company were asked to indicate the number of speeding tickets they had received in the past three years. The minimum value in the data was zero and the largest was six tickets. If you wished to illustrate the proportion of people who had three or fewer tickets, you would most likely construct a cumulative relative frequency distribution.
True
One of the key differences between a bar chart and histogram is:
a bar chart is used to display a categorical variable and a histogram is used to display the distribution of a quantitative variable.
A census is an enumeration of the entire sample of items selected from the population of interest
false
A cumulative frequency distribution shows the percentage of observations for the variable of interest with values less than or equal to the upper limit of each class.
false
A data set in which the mean, median, and mode are all equal is said to be a skewed distribution.
false
A distribution is said to be symmetric when the sample mean and the population mean are equal.
false
A histogram can be constructed for data that are either quantitative or qualitative
false
A histogram can be used to display a joint frequency distribution between two quantitative variables.
false
A histogram is an effective tool for graphically describing a joint frequency distribution
false
A lakeside neighborhood in Washington is home to a couple of successful baseball and football players in Seattle. If news articles usually report the median household income in that neighborhood rather than the mean income, this would be because income is a left-skewed distribution.
false
A marketing manager for the Verizon cell phone company selected a random sample of 250 customers from the list of 10,556 total customers in a particular region. The mean monthly bill for the last six months based on the sample data is $65.70. The manager should realize that the mean bill for all 10,556 customers will actually be much higher than the sample mean of $65.70.
false
A pie chart is almost always constructed when the variable of interest is qualitative.
false
A statistic is a value that describes a population characteristic while a parameter is computed from a sample.
false
A university recently collected data for a sample of 200 business majors. One variable collected was the number of credits left to be taken before graduation. This variable could effectively be displayed using a line chart.
false
An Internet-based or emailed survey is not an alternative method of data collection.
false
An accountant who recently examined 200 accounts from a company's total of 4,000 accounts in an effort to estimate the percentage of all accounts that have incorrect journal entries is using descriptive statistical analysis to reach the conclusion
false
An open-end question requires respondents to choose from a short list of choices
false
Cluster sampling is the same thing as stratified random sampling.
false
Data collected on marital status (married, divorced, single, other) would be an ordinal level variable
false
Data collected on the Internet can generally be considered accurate since the data must go through a screening process before they can be placed on the Internet.
false
Data collected using open-end questions is generally easier to analyze than data collected from closed-end questions.
false
Frequency distributions are specifically for analyzing discrete data.
false
If you wish to construct a graph of a relative frequency distribution, you would most likely construct an ogive.
false
In a recent study at First National Bank, a frequency count was made for the variable marital status for the bank's 10,000 customers. It would also be appropriate to develop a histogram for this variable to show how marital status is distributed.
false
In a recent study of the sales prices of houses in a Midwestern city, the mean sales price has been reported to be $167,811 while the median sales price was $155,600. From this information, you can determine that the data involved in the study are left-skewed.
false
In a report describing the number of people in the family of each of the 400 employees at a manufacturing company, the frequency count at the value 3 was 220. This means that the relative frequency at the 3 level is .44.
false
In a study involving car owners, one question asked the owner for the number of miles driven last year. A second question asked the owner for the age of the vehicle. A histogram would be useful for analyzing the relationship between miles driven and the age of the vehicle.
false
In an unstructured interview the questions are scripted
false
In constructing a frequency distribution for the savings account balances for customers at a bank, the following class boundaries might be acceptable if the minimum balance is $5.00 and the maximum balance is $18,700: $0.00 - $5,000 $5,000 - 10,000 $10,000 - $15,000 $15,000 - $20,000
false
It is possible for a set of data to have multiple modes as well as multiple medians, but there can be only one mean.
false
Nominal data is the highest level of data
false
One of the most common statistical sampling techniques is convenience sampling.
false
Possibly the most frequently used nonstatistical sampling procedure is the simple random sample
false
Recently an article in a newspaper stated that 75 percent of the households in the state had incomes of $20,200 or below. Given this input, it is certain that mean household income is less than $20,200.
false
Recently, an analyst in a company's marketing department surveyed customers regarding how often they buy a particular product. One customer indicated that she purchased the product 17 times in the last six months, but the analyst recorded the response as 71 times. This is an example of observer bias
false
Scatter diagrams can be used for either quantitative or qualitative data.
false
The second quartile for a set of data will have the same value as the 50th percentile only when the data are symmetric.
false
The symbol µ is used to represent the sample mean.
false
Two separate frequency distributions for two variables provide the same information as one joint frequency distribution involving the same two variables.
false
When a histogram is constructed for discrete numerical data, there should be spaces between the bars of the histogram.
false
When a survey is done you can always assume that non-respondents would have answered the same way as those who did respond
false
When developing a frequency distribution, the following bin classifications follow the definition of appropriate intervals of a variable: 0 to < 10 10 to < 20 20 to < 25
false
When developing a scatter diagram, it is appropriate to connect the points on the graph with straight lines or the lines can be omitted.
false
When surveyed, a sample of 1,250 patients at a regional hospital provided interviewers with the following summary statistics pertaining to the hospital charges: Minimum = $278.00 Q1 = $1,245 Q2 = $3,567 Q3= $4,702. Based on these data, if you were to construct a box and whisker plot, the value $278 would be considered an outlier
false
When surveyed, a sample of 1,250 patients at a regional hospital provided interviewers with the following summary statistics pertaining to the hospital charges: Minimum = $278.00 Q1 = $1,245 Q2 = $3,567 Q3= $4,702. Based on these data, the distribution is seen to be symmetric
false
When the United States conducts a census that counts all people in the country, this is an example of using a sample
false
When university newspaper reporters take a poll of students by standing outside of the nearest pub to survey students about the university offering upgraded food options, the sampling method used is called a random sample
false
A consumer products company wants to interview customers regarding a new product. If it wishes to adhere to a predetermined pattern of questions in the interview, which of the following would likely be used?
structured interview
A common underpinning of all statistical sampling techniques is the concept of random selection
true
A histogram can be created for discrete or continuous data.
true
A major insurance company believes that for drivers between 16 years of age and 60 years of age, the number of accidents per year tends to decrease as age increases. If this is the case, a scatter diagram should show a negative relationship between the two variables.
true
A manufacturing manager has developed a table that shows the average production volume each day for the past three weeks. The average production level is an example of a numerical measure.
true
A recent study involving a sample of 3,000 vehicles in California showed the following statistics related to the number of miles driven per day: Q1 = 12, Q2 = 45, and Q3 = 56. Based on these data, we know that the distribution is skewed.
true
A sales manager has five salespeople. The following are the number of units sold by the five salespeople during the past week: {5, 13, 6, 2, 4}. Based on the data, the mean number of units sold was 6 units
true
A sample is selected from a population in cases where selecting data from the entire population is either very difficult or very expensive
true
A scatter diagram can show whether a pair of variables has a strong or weak relationship, and also whether it is linear or curved.
true
A small engine repair shop tracks the number of customers who call each day. This variable is a time-series variable and also ratio level
true
A study of 2000 Verizon cellphone customers listed the annual incomes of the customers as well as other variables. The lowest income was $25,000 and the highest income was $145,000. To develop a frequency distribution with 6 classes, the smallest value that the class width can be is 20K.
true
A study was recently conducted in which makers of toothpaste tracked sales for the month at different stores in a market area. The variable of interest was the number of units sold. The numbers ranged from 1,200 to 22,700. In this case, the stems in a stem and leaf diagram might be values such as 1 and 22 while the leaves would be 200 and 700.
true
A variable that has all the properties of an interval variable, but also has a true zero, is a ratio level variable.
true
A variable, i.e., the length of time it takes for an employee to complete an assembly procedure at an automotive plant, is a ratio level variable.
true
After developing a frequency distribution for a quantitative variable, a histogram can be developed with the horizontal axis representing the values of the variable and the vertical axis representing the frequency of occurrence in each class or group.
true
An accountant has recently prepared a report for a client that contains a variety of graphs and charts. In doing so, she has used descriptive statistical methods.
true
An ogive is a graph that shows cumulative relative frequency
true
Another name for a joint frequency distribution is a cross-tabulation table.
true
At the end of the school term, students are asked to rate the course and instructor by indicating on a scale of 1-5 how well they liked the course. The data generated from this question are examples of ordinal data
true
Bar charts can show either frequency or percentage
true
Bar charts can typically be formed with the bars vertical or horizontal without adversely affecting the interpretation.
true
Companies frequently use charts and graphs in their regular communications with stockholders and investors; this shows the use of descriptive statistics
true
Data are considered to be right-skewed when the mean lies to the right of the median.
true
Hypothesis testing and estimation are two statistical tools that are used to draw inferences about a large data set based on a subset of the data.
true
If a set of data has 1,500 values, the 30th percentile value will correspond to the 450th value in the data when the data have been arranged in numerical order.
true
If a state agency wishes to conduct on-site surveys of small businesses throughout the state, cluster sampling could potentially be used to reduce the geographical area over which the surveys would need to be conducted
true
If after graphing the data for a quantitative variable of interest, you notice that the distribution is highly skewed in the positive direction, the measure of central location that would likely provide the best assessment of the center would be the median.
true
In a study involving car owners, one question asked the owner for the number of miles driven last year. A second question asked the owner for the age of the vehicle. A joint frequency distribution would be useful for determining whether newer cars tend to be driven more miles than older cars
true
In preparing a line chart, the horizontal axis shows time and the vertical axis shows the value of the variable of interest
true
It is often a good idea to convert frequency distributions to relative frequency distributions when you wish to compare two distributions with different amounts of data.
true
Mail questionnaires typically generate poor response rates
true
On a scatter diagram, the independent variable should be placed on the horizontal axis and the dependent variable should be placed on the vertical axis.
true
On a survey, the questions pertaining to the background of the respondent (age, gender, etc.) are referred to as demographic questions.
true
One of the differences between a stem and leaf diagram and a histogram is that even for variables involving a large number of different values, the stem and leaf diagram shows the individual data values whereas the histogram requires you to group the data and lose the individual values.
true
One of the primary advantages of using the median as a measure of the center for a set of data is that the median is not affected by extreme values in the data.
true
One way to improve the response rate for a survey is to administer the surveys directly to the respondents.
true
Population parameters are descriptive numerical measures, such as an average, that describe the entire population.
true
Sales data measured each week for the past twenty weeks are examples of time-series data
true
Sawyer & Company is a law firm in Dallas, Texas. Recently, the administrative manager prepared a report for the managing partners that showed the number of court cases handled by the firm monthly over the past three years. One of the objectives of graphing these data might have been to identify a trend in the number of court cases.
true
Simple random sampling involves selecting members of the population in such as way that all members are equally likely to be chosen
true
Some of the most common methods of collecting data include experiments, telephone surveys, mail questionnaires, direct observations, and personal interviews.
true
The Georgia Company, a pharmaceutical company, recently conducted a study in which 20 people were given a new drug and 20 other people were given a placebo. The objective was to determine whether there was a difference in pain relief between those using the new drug versus those using the placebo. The data collection used here is an example of an experiment
true
The Parks and Recreation manager for the city of Detroit recently submitted a report to the city council in which he indicated that a random sample of 500 park users indicated that the average number of visits per month was 4.56. This value should be viewed as a statistic by the city council.
true
The appropriate number of classes should generally be between 5 and 20
true
The editor of a local newspaper is interested in determining the percentage of subscribers who read the paper's editorials. The statistical technique that he would use is called estimation.
true
The marketing division of a company is interested in determining whether increased advertising will increase sales in three of its target cities. Three levels of advertising are used and the sales are recorded for the month immediately following the ads. In this case, the data are considered to have been collected using an experiment.
true
To show the relationship between amount of rainfall and the number of car accidents, the best type of graph to use is a scatter diagram
true
When analyzing annual incomes of adults in a market area, the marketing manager's report indicated that the 90th percentile is $123,400. That means that 90 percent of the adult incomes in the market area fall at or below $123,400.
true
When people fail to respond to a survey, the data collection process may suffer from nonresponse bias.
true
When stratified random sampling is employed, the population is divided into homogeneous subgroups called strata.
true
When students are asked to list their age and the percentage of their college expenses that they pay for themselves, the type of data being collected is quantitative.
true
When the median of a data set is 110 and the mean is 127, the percentile associated with the mean must be higher than 50 percent.
true
One of the major challenges for developing a good written questionnaire or telephone survey instrument is that
wording can influence responses
Assuming you have data for a variable with 2,000 values, using the 2k L n guideline, what is the least number of groups that should be used in developing a grouped data frequency distribution?
11
Which of the following is an acceptable format for setting up class boundaries for a frequency distribution?
200 to 299.99, 20 to under 40, 20 to 40 are all acceptable
A study was recently done in which the brand preference for breakfast cereal was analyzed against the gender of the shopper. The study consisted of 200 male shoppers and 300 female shoppers. Three different cereal brands were considered: A, B, and C. A total of 250 female shoppers preferred brand A, 25 female shoppers preferred brand C. The number of female shoppers that preferred brand B was:
25
When an accounting auditor randomly selects 20 accounts from all the accounts to check for accuracy, she has selected:
A sample from the population
Frequency distributions can be formed from which of the following types of data?
Both discrete and continuous
The human resources department at a major high tech company recently conducted an employee satisfaction survey of 100 of its 3,000 employees. Data were collected on such variables as age, gender, marital status, current salary, level of overall satisfaction on a scale from 1 to 5, number of years with the company, and job title. Which of the following best describes the overall data set that was generated from the study?
Cross-sectional
A company is interested in determining which of several advertising layouts is most effective at generating additional sales. The data collection tool that would most likely be used in this situation is:
Experiment
In this course, the term business statistics refers to the set of tools and techniques that are used to convert information into meaningful data
False
A car manufacturer stated in its advertising that the gas mileage for its hybrids will be greater than 40 mpg on average. A consumer agency tested a sampling of the hybrids under a variety of conditions. Based on these tests, the agency concluded that the manufacturer was justified in making this claim. The process described is an example of:
Hypothesis testing and statistical inference
A histogram is most commonly used to analyze which of the following?
Quantitative data
General Electric Corporation tracks employee turnover annually. It currently has a data set that contains turnover for the past 20 years. What type of data does it have?
Time-series data
) For the same data, a graph of a relative frequency distribution will look exactly the same as a graph of the frequency distribution.
True
A sampling plan that requires a person to interview 100 people as they exit a department store would most likely be:
a convenience sample
An Internet service provider has the capability of tracking the time that each of its customers spends connected to the Internet during a month. These data would constitute:
a population
A common rule of thumb for determining how many classes to use when developing a frequency distribution with classes is:
between 5 and 20 classes
When an administrator at a local hospital prepares a series of charts and graphs pertaining to the patients that have stayed at the hospital during the past month, she is using which general category of statistical analysis? A) Random sampling B) Quantitative statistics C) Descriptive statistics D) Inferential statistics
descriptive statistics
A box and whisker plot shows where the mean value falls relative to the median for a variable
false
A pharmaceutical company conducts a study where 50 patients are given a drug. They find that 10 percent of patients experience nausea as a side effect. This 10 percent is an example of a parameter
false
A statistic is just another name for a parameter.
false
Selection bias occurs when the respondent decides which of the questions on the survey to answer
false
Statistics are measures computed from the entire population of data
false
The Wilson company monitors customer complaints and organizes these complaints into six distinct categories. Over the past year, the company has received 534 complaints. One possible graphical method for representing these data would be a histogram.
false
The method of data collection called direct observation is always associated with gathering data from people
false
The owner of a local gasoline station has kept track of the number of gallons of regular unleaded sold at his station every day since he purchased the station. This morning, he computed the mean number of gallons. This value would be considered a statistic.
false
The Canyon Water Company collects data on the number of gallons of water consumed during a month for each customer. The production manager has divided the usage into 6 classes. To display these data effectively, she could use which of the following types of graphs to convey information about the water usage?
histogram or pie chart
A line chart is most appropriate for:
time-series data
A joint frequency distribution can be constructed for either quantitative or qualitative data
true
A light bulb manufacturer wants to advertise the average life of its light bulbs so it tests a subset of light bulbs. This is an example of inferential statistics.
true
Descriptive statistical tools include graphs, charts, and numerical measures.
true
Experimental design is a plan for performing an experiment where the effects of one or more factors on the variable of interest are measured.
true
The regional sales manager for a medical supply company recently collected data on the reasons why customers returned the merchandise for a refund. She actually formed a frequency distribution for this variable. It would now be acceptable to construct a bar chart to graphically display the results
true
The right and left edges of the box in a box and whisker plot represent the 3rd and 1st quartiles, respectively.
true
The sales data for a company measured in the week following an increased ad campaign would be considered cross-sectional data
true
The sample mean is an estimate of µ and may be either higher or lower than µ depending on the sample.
true
There is no hard-and-fast rule regarding the number of classes that must be used when establishing a frequency distribution for a continuous variable.
true