ISDS 361B Midterm 1

r squared formula

SSR/SST

Naive Approach

a forecasting technique which assumes that demand in the next period is equal to demand in the most recent period

DJ needs to display data over time. Which of the following charts should DJ use? a. Line chart b. Bar chart c. Pie chart d. Scatter chart

a. Line chart

Deleting the grid lines in a table and the horizontal lines in a chart ______. a. increases the data-ink ratio b. does not affect the data-ink ratio c. decreases the data-ink ratio d. increases the non-data-ink ratio

a. increases the data-ink ratio

Which of the following is a graphical presentation of the relationship between two quantitative variables? a. a bar chart b. a scatter chart c. a pie chart d. a histogram

b. a scatter chart

The amount of time taken by each of 12 students in a class to complete an exam is an example of what type of data? a. cannot be determined b. quantitative data c. time series data d. categorical data

b. quantitative data

Given forecast errors of 5, 0, -4, and 3, what is the mean absolute forecast error? a. 4 b. 1 c. 3 d. None of the choices e. 2.5

c. 3

In a(n) ________________, one or more variables are identified and controlled or manipulated so that data can be obtained about how they influence the variable of interest identified first. a. Regression study b. None of the choices c. Experimental study d. Variable study e. Observational study

c. Experimental study

Tables should be used instead of charts when _____. a. the reader need not differentiate the columns and rows b. the reader needs relative comparisons of data c. the values being displayed have different units or very different magnitudes d. there are more than two columns of data

c. the values being displayed have different units or very different magnitudes

A quantity of interest that can take on different values is known as which of the following? a. a parameter b. an observation c. a sample d. a variable

d. a variable

The letter grades (A, B, C, D, F) of business analysis students are recorded by a professor. This variable's classification is which of the following? a. cannot be determined b. time series data c. quantitative data d. categorical data

d. categorical data

In a simple linear regression analysis the quantity that gives the amount by which the dependent variable changes for a unit change in the independent variable is called the: a. none of the choices b. coefficient of determination c. correlation coefficient d. slope of the regression line e. standard error

d. slope of the regression line

The difference in a variable measured over observations (time, customers, items, etc.) is known as which of the following? a. observed differences b. variable change c. descriptive analytics d. variation

d. variation