Exam 2: Basic Descriptive Statistics: Percentages, Ratios and Rates, Tables, Charts, and Graphs

Which of the following should be reflected in a frequency distribution?

Table 2.1 Age of Respondents -According to Table 2.1, what is the width of each interval if 60 cases range in score from 4 to 84, and 10 intervals in a frequency distribution are wanted?

Table 2.2 Number of Prior Convictions among Inmates at a Prison -Which of the following best characterizes the values in the prior convictions column in Table 2.2.

Table 2.2 Number of Prior Convictions among Inmates at a Prison -What would be an ideal graph to represent the data shown in Table 2.2?

A company has 8 entry-level workers and 4 managers. What is the ratio of managers to entry-level workers?

The variable "number of fitness centres" across 25 districts of a large city ranges from 3 to 23. How wide should the interval width be if we desired 5 intervals?

A researcher presents a figure to depict how many heroin sales were made last year by members of a large gang. Interval values for the variable border each other, representing the data as a continuous series. What type of graphing technique is the researcher using?

Table 2.2 Number of Prior Convictions among Inmates at a Prison -In Table 2.2, what would be the value for the cumulative percentage corresponding to the 9-11 prior conviction group?

Table 2.2 Number of Prior Convictions among Inmates at a Prison -In Table 2.2, what percentage of cases are in the 6-8 prior conviction group?

In June 2014, the entire province of Manitoba had a population of 985,900 working-age adults, and 668,300 of them were participating in the labour force. What percentage of the working-age population was participating in the labour force?

Why do researchers commonly use intervals when representing frequency distributions for interval-ratio variables, and what principles should guide them when constructing such frequency distributions? • Interval-ratio variables tend to have many possible values. Aggregating a range of values helps provide a more manageable way to understand how the variable is distributed rather than showing the frequency of every possible score. • Scores should be grouped to maximize clarity and ease of comprehension. A general guiding principle is that one should balance detail (a large number of narrow categories) with compactness (a smaller number of wide categories). • Another general rule for using intervals is that they should be equal in size.

Which of the following is a requirement for creating a frequency distribution?

Which of these distributions appropriately illustrates real limits?

Why do frequency distributions of interval-ratio-level data seldom contain more than 15 intervals?

Below are skills test scores for applicants of a software engineering job. Put the data into a frequency distribution using intervals of size 8. Include columns for percentages and cumulative percentages.

How is a proportion calculated?

What would be the appropriate graph to show the distribution of Canadian-born versus non-Canadian-born students in an introductory economics class?

How does a frequency polygon differ from a histogram?

An environmental scientist reports that the proportion of lakes in a region that are contaminated by pollution is 0.28. How would this value be written as a percentage?

The intervals below represent ages of respondents. Which set of intervals is both exhaustive and mutually exclusive?