OIS Ch1&2 HW
Possibly the most frequently used nonstatistical sampling procedure is the simple random sample. True False
False
When a marketing manager surveys a few of the customers for the purpose of drawing a conclusion about the entire list of customers, she is applying: quantitative models. descriptive statistics. numerical measures. inferential statistics.
inferential statistics.
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. graphical tools. statistical charts. histograms or bar charts.
numerical measures.
Which of the following is an example of graphs used to describe data? Histograms Bar charts Both A and B are correct. None of the above.
Both A and B are correct.
An open-end question requires respondents to choose from a short list of choices True False
False
Cross-sectional data is a set of data values observed at successive points in time. True False
False
Data collected on marital status (married, divorced, single, other) would be an ordinal level variable. True False
False
Descriptive statistics allow a decision maker to reach a conclusion about a population based on a subset from the population. True False
False
In a scatter plot the points should always be connected with a line. True False
False
The difference between interval data and ratio data is that interval data has a natural zero. True False
False
The sales data for a company measured weekly for the past year would be considered cross-sectional data since the sales values are computed from the entire company. True False
False
A histogram can be constructed for data that are either quantitative or qualitative. True False
False * Histograms are used to represent a frequency distribution associated with a single quantitative (ratio or interval - level) variable. * The variable on the horizontal axis (for histograms) is numerical, w/ values moving from low to high * The vertical axis (for histograms) shows the frequency count, or relative frequency, for each numerical value or range of values *There is no gap between the bars.
When a histogram is constructed for discrete numerical data, there should be spaces between the bars of the histogram. True False
False *That would be a bar chart! Not a histogram. *Bar charts are used when one or more variables of interest are categorical
A histogram is most commonly used to analyze which of the following? Time-series data Ordinal data Quantitative data Nominal level data
Quantitative data * Histograms are used to represent a frequency distribution associated with a single quantitative (ratio or interval - level) variable. * The variable on the horizontal axis (for histograms) is numerical, w/ values moving from low to high * The vertical axis (for histograms) shows the frequency count, or relative frequency, for each numerical value or range of values *There is no gap between the bars.
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 False
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 False
True
A short survey with closed-end questions is likely to have a better response rate than a long survey with open-ended questions. True False
True
A variable that has all the properties of an interval variable, but also has a true zero, is a ratio level variable. True False
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 False
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 False
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 False
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 False
True
Bar charts can typically be formed with the bars vertical or horizontal without adversely affecting the interpretation. True False
True
Flavors of ice cream (chocolate, vanilla, strawberry, etc.) are an example of nominal data. True False
True
Histograms cannot have gaps between the bars, whereas bar charts can have gaps. True False
True
If a scatter diagram shows points that are reasonably aligned and are sloping downward from left to right, this implies that there is a negative linear relationship between the two variables. True False
True
On a survey, amount of education is recorded as some high school, high school graduate, some college, college graduate, etc. This is an example of ordinal data. True False
True
Recording vehicle type as sedan, minivan, pick-up truck, etc. is an example of qualitative data. True False
True
Sales data measured each week for the past twenty weeks are examples of time-series data. True False
True
Simple random sampling involves selecting members of the population in such as way that all members are equally likely to be chosen. True False
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 False
True
When using the Histogram tool in Excel to construct a frequency distribution and histogram, the bins represent the upper class limits. True False
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 False
True * Scatter Diagram or Scatter plot is a procedure used to study two quantitative variables simultaneously (just like joint frequency distributions that allow decision-maker to examine two variable at the same time) *Shows the relationship between two quantitative variables - Example: A company would like to know the relationship between sales an advertising Dependent variable - Values are thought to be a function of another variable Independent variable - Values are thought to impact the values of the dependent variable
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 False
True *Look over this example this demonstrate the income and experience you have done over the past until now. scatter plot help demonstrate your hard work and moving up created you to receive a higher income. it help to put a line and say it is a positive liner scatter plot.
The use of charts and graphs is an example of: inferential statistics. descriptive statistics. hypothesis testing. estimation.
descriptive statistics.
A bar chart is most likely used to display which of the following? A continuous variable A nominal level variable An ordinal level variable Either B or C
Either B or C * The bar chat may be - Vertical ( Ordinal/Sequential) - Horizontal (Nominal / Categorical)
A cell phone service provider has 14,000 customers. Recently, the sales department selected a random sample of 400 customer accounts and recorded the number of minutes of long distance time used during the previous billing period. The data for this variable is considered to be nominal since the values are based on sample data. True False
False
Nominal data is the highest level of data. True False
False
To show how the price of a stock has changed over the last 3 months, the best type of chart to use is: a histogram. a line chart. a bar chart. a pie chart.
a line chart. * Histograms are used to represent a frequency distribution associated with a single quantitative (ratio or interval - level) variable. * The variable on the horizontal axis (for histograms) is numerical, w/ values moving from low to high * The vertical axis (for histograms) shows the frequency count, or relative frequency, for each numerical value or range of values *There is no gap between the bars. Line chart - a two-dimensional chart showing time on the horizontal axis and the variable of interest on the vertical axis. bar chart - a graphical representation of a categorical data set in which a rectangle or bar is drawn each category or class * The length or height or each bar represents the frequency or percentage of observations or some other measure associated with the category. *The bar may be vertical (ordinal)or horizontal (nominal) Pie chart - * A graph in the shape of a circle. *The circle is divided into "slices" corresponding to the categories or classes to be displayed * The size of each slice is proportional to the magnitude of the displayed variable associated with each category or class.
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. equal to 0.25 times the number of data values. at least 10 classes. no fewer than 6 classes.
between 5 and 20 classes.
