ch 2 BA with quiz
Select the histogram that is moderately skewed right.
A histogram is said to be skewed to the right if its tail extends farther to the right than to the left. Histogram B is moderately skewed to the right. Histogram D is highly skewed right.
regression analysis
A statistical tool that examines the relationship between two or more variables so that one may be predicted from the other(s).
The charts that are helpful in making comparisons between categorical variables are a. column charts and line charts. b. bar charts and column charts. c. bar charts and scatter charts. d. scatter charts and line charts.
Bar charts and column charts provide a graphical summary of categorical data, and they are very helpful in making comparisons between categorical variables.
Which of the following graphs cannot be used to display categorical data? Pie chart b. Stacked-column chart c. Clustered-column chart d. Scatter chart
Scatter chart A scatter chart is a graphical presentation of the relationship between two quantitative variables. One variable is shown on the horizontal axis, and the other on the vertical axis
Which of the following relationships would have a negative correlation coefficient? a Cost of a car and the amount of tax to be paid b. Supply and demand c. Amount of a bill at a restaurant and the amount of the tip d. The square footage of a home and the price of the home
Supply and demand A relationship will have a negative correlation coefficient if as one variable increases the other variable decreases.
total relative frequency?
The relative frequencies always add to 1
The distribution of hourly sales for a local family owned store is normally distributed with a mean of $225 per hour and a standard deviation of $75 per hour. Which of the following intervals contains the middle 95% of hourly sales? a. $75 to $375 b. $125 to $325 c. $175 to $275 d. $150 to $300
a. $75 to $375 In a normal curve, approximately 95% of observations fall within 2 standard deviations of the mean
Compute the median of the following data. 32, 41, 36, 24, 29, 30, 40, 22, 25, 37 a. 31 b. 40 c. 34 d. 28
a. 31 30+32/2
Compute the mean of the following data. 56, 42, 37, 29, 45, 51, 30, 25, 34, 5 a. 40.6 b. 42.8 c. 39.4 d. 52.1
a. 40.6 The mean provides a measure of central location for the data. It is computed as: 56+42+37+29+45+51+30+25+34+5/10
A data visualization tool that updates in real time and gives multiple outputs is called a. a data dashboard. b. the GIS. c. a metrics table. d. a data table
a. a data dashboard. A data dashboard is a data visualization tool that illustrates multiple metrics and automatically updates these metrics as new data become available.
The correlation coefficient will always take values a. between -1 and 0. b. between -1 and +1. c. greater than 0. d. less than -1.
b. between -1 and +1. The correlation coefficient will always take values between -1 and +1.
Any data value with a z-score less than -3 or greater than +3 is considered to be a(n) a. z-score value. b. outlier. c. whisker. d. statistic.
b. outlier. Any data value with a z-score less than -3 or greater than +3 is treated as an outlier.
A __________ is used for examining data with more than two variables, and it includes a different vertical axis for each variable. a. scatter plot b. parallel-coordinates plot c. column chart d. PivotChart
b. parallel-coordinates plot One type of helpful chart for examining data with more than two variables is the parallel-coordinates plot, which includes a different vertical axis for each variable
Tables should be used instead of charts when .a the reader need not differentiate the columns and rows. b. the values being displayed have different units or very different magnitudes. c. the reader needs relative comparisons of data. d. there are more than two columns of data.
b. the values being displayed have different units or very different magnitudes. Tables should be used when the reader needs to refer to specific numerical values, when the reader needs to make precise comparisons between different values and not just relative comparisons, and when the values being displayed have different units or very different magnitudes.
The goal regarding using an appropriate number of bins is to show the a. number of observations. b. variation in the data. c. number of variables. d. correlation in the data.
b. variation in the data. The goal is to use enough bins to show the variation in the data, but not so many classes that some contain only a few data items
Compute the third quartile for the following data. 10, 15, 17, 21, 25, 12, 16, 11, 13, 22 a. 15.5 b. 21.5 c. 21.25 d. 11.75
c. 21.25 Quartiles divide data into four parts, with each part containing approximately one-fourth, or 25 percent, of the observations. This can be calculated with the Excel function =QUARTILE.EXC(range,3) = 21.25.
Consider the data below. What percentage of students scored grade C? Grades Number of students A 16 B 28 C 33 D 13 Total 90 a. 33% b. 31% c. 37% d. 28%
c. 37% A percent frequency distribution summarizes the percent frequency of the data for each bin. The percent frequency of a bin is the relative frequency multiplied by 100. 33/90 = 37%.
The amount of time taken by each of 10 students in a class to complete an exam is an example of what type of data? a. Time series data b. Cannot be determined c. Quantitative data d. Categorical data
c. Quantitative data Data are considered quantitative data if numeric and arithmetic operations, such as addition, subtraction, multiplication, and division, can be performed on them.
A chart that is recommended as an alternative to a pie chart is a a. box plot. b. stacked column chart. c. bar chart. d. line chart.
c. bar chart. Making visual comparisons is much easier in the bar chart than in the pie chart. It is recommended against using pie charts in most situations and suggested using bar charts for comparing categorical data instead.
An alternative for a stacked column chart when comparing more than a couple of quantitative variables in each category is a a. clustered bar chart. b. pie chart. c. clustered column chart. d. stacked bar chart.
c. clustered column chart. Experts often recommend against the use of stacked column bar charts for more than a couple of quantitative variables in each category. An alternative chart for these same data is called a clustered column (or bar) chart.
If covariance between two variables is near 0, it implies that a. the variables are strongly related. b. a positive relationship exists between the variables. c. the variables are not linearly related. d. the variables are negatively related.
c. the variables are not linearly related. If the covariance between two variables is near 0, then the variables are not linearly related.
Data collected from several entities over a period of time (minutes, hours, days, etc.) are called a. cross-sectional data. b. source data. c. time series data. d. categorical and quantitative data.
c. time series data Data that are collected over a period of time (minutes, hours, days, months, years, etc.) are known as time series data.
Compute the coefficient of variation for the following sample data. 32, 41, 36, 24, 29, 30, 40, 22, 25, 37 a. 18.64% b. 20.28% c. 21.67% d. 21.36%
d. 21.36% The coefficient of variation indicates how large the standard deviation is relative to the mean. The coefficient of variation is (6.75 / 31.6 × 100) = 21.36%.
se technology to compute the standard deviation for the following sample data. 32, 41, 36, 24, 29, 30, 40, 22, 25, 37 a. 6.41 b. 5.42 c. 5.96 d. 6.75
d. 6.75 The standard deviation is defined to be the positive square root of the variance and can be calculated using the Excel function =STDEV.S( ).
A sample of 13 adult males' heights are listed below. 70, 72, 71, 70, 69, 73, 69, 68, 70, 71, 67, 71, 74 Find the range of the data. a. 6.5 b. 5 c. 4 d. 7
d. 7 The simplest measure of variability is the range. The range can be found by subtracting the smallest value from the largest value in a data set. Range = 74 - 67 = 7.
time series data
line chart
cross-sectional data
scatter chart
