Chapter 2

Question 1

demographgers examine

Answer 1

s examine the size, composition, and distribution of human populations.

Question 2

To make sense out of
these data, a researcher has to organize and summarize the data in some systematic fashion.
In this chapter, we review two such methods used by social scientists:

Answer 2

) the creation of

frequency distributions and (2) the use of graphic presentation

Question 3

The most basic way to organize data is to classify the observations into a frequency
distribution. A frequency distribution is

Answer 3

a table that reports the number of observations
that fall into each category of the variable we are analyzing. Constructing a frequency
distribution is usually the first step in the statistical analysis of data

Question 4

Frequency distributions are helpful in

Answer 4

n presenting information in a compact form

Question 5

what abt when the # of cases is large? what to do then?

Answer 5

However,
when the number of cases is large, the frequencies may be difficult to grasp. To standardize
these raw frequencies, we can translate them into relative frequencies—that is, proportions
or percentages

Question 6

what is a proportion and how to find one

Answer 6

A proportion is a relative frequency obtained by dividing the frequency in each category by
the total number of cases. To find a proportion (p), divide the frequency (f) in each
category by the total number of cases (N

p= f/n - examle of a q on pg 65

Question 7

whats another way to express a frequency and define it

Answer 7

We can also express frequencies as percentages. A percentage is a relative frequency
obtained by dividing the frequency in each category by the total number of cases and
multiplying by 100. In most statistical reports, frequencies are presented as percentages
rather than proportions. Percentages express the size of the frequencies as if there were a
total of 100 cases.

Question 8

For nominal and ordinal variables, constructing a frequency distribution is quite simple. To
do so

Answer 8

count and report the number of cases that fall into each category of the variable
along with the total number of cases (N).

Question 9

. To convert

the Frequency column to percentages, what do u do and when are percentage distributions especially important?

Answer 9

simply divide each frequency by the total number of
cases and multiply by 100. Percentage distributions are routinely added to almost any
frequency table and are especially important if comparisons with other groups are to be
considered

Question 10

what is the major difference between frequency distributions for nominal and ordinal vbles

Answer 10

the order in which the categories are listed. The categories for nominal-level variables do
not have to be listed in any particular order. For example, we could list females first and
males second without changing the nature of the distribution. Because the categories or
values of ordinal variables are rank-ordered, however, they must be listed in a way that
reflects their rank—from the lowest to the highest or from the highest to the lowest. Thus,
the data on degree in Table 2.5 are presented in declining order from “less than high
school” (the lowest educational category) to “graduate” (the highest educational category).

Question 11

why are simple frequency distributions difficult to read

Answer 11

Very often interval-ratio variables have a wide range of values

Question 12

good example of frequency distributions on pg 76

Answer 12

ok lol

Question 13

Cumulative frequency distribution

Answer 13

A distribution showing the frequency at or below each category (class
interval or score) of the variable

Question 14

Cumulative frequencies are appropriate only

Answer 14

for variables that are measured at an ordinal

level or higher

Question 15

how are cumulative frequencies obtained

Answer 15

. They are obtained by adding to the frequency in each category the
frequencies of all the categories below it.

Question 16

problem w stated limits v real limits

Answer 16

Though age is conventionally rounded
down, let’s suppose for a moment that respondent’s age had been reported with more precision. Where
would you classify a woman who was 49.25 years old? Notice that her age would actually fall between the
intervals 40–49 and 50–59! To avoid this potential problem, use the real limits shown in the following table
rather than the stated limits listed in Table 2.8.
Real limits extend the upper and lower limits of the intervals by .5. For instance, the real limits for the
interval 40–49 are 39.5–49.5; the real limits for the interval 50–59 are 49.5–59.5; and so on

Question 17

how to construct a cumulative frequency distribution

Answer 17

start with the frequency in the lowest
class interval (or with the lowest score, if the data are ungrouped), and add to it the
frequencies in the next highest class interval. Continue adding the frequencies until you
reach the last class interval. The cumulative frequency in the last class interval will be equal
to the total number of cases (N)

Question 18

cumulative percentage distribution and how is it made

Answer 18

which has wider
applications than the cumulative frequency distribution (Cf). A cumulative percentage
distribution shows the percentage at or below each category (class interval or score) of the
variable. A cumulative percentage distribution is constructed using the same procedure as
for a cumulative frequency distribution except that the percentages—rather than the raw
frequencies—for each category are added to the total percentages for all the previous
categories.

Question 19

what does the study with asking blacks n whites abt immigrants imply and what questions could it bring up?

Answer 19

These data prompt many
other questions about the role that race or other variables may play in attitudes about legal
and unauthorized immigration. What explains the difference between white and black
respondents? What would the differences be if we compared men with women? Whites
with Latinos? Employed with unemployed individuals

Question 20

. But what exactly are rates, and how are they constructed?

Answer 20

A rate is obtained by
dividing the number of actual occurrences in a given time period by the number of possible
occurrences.

rate= f/population

Question 21

2014 poverty rate can b expressed as

Answer 21

number of ppl in poverty in 2014/total population in 2014

Question 22

The poverty rate in 2014 as reported by the U.S. Census Bureau was 15% (.15 × 100).
This means that …

Answer 22

for every 1,000 people, 150 were poor according to the U.S. Census
Bureau definition

Question 23

why are rates usually expressed as rates per thousad or hundred thousand

Answer 23

to

eliminate decimal points and make the number easier to interpret.

Question 24

how to read a statistical table? what do the headings, subheadings and main body show?

Answer 24

1The first step in reading any statistical table is to understand what the researcher is trying to
tell you. Begin your inspection of the table by reading its title, as the title usually describes
the central contents of the table.

2Check for any source notes to the table; such notes reveal
the source of the data or the table and any additional information that the author considers
important.

3 Next, examine the column and row headings and subheadings. These identify
the variables, their categories, and the kind of statistics presented, such as raw frequencies or
percentages.

4The main body of the table includes the appropriate statistics (frequencies,
percentages, rates, etc.) for each variable or group as defined by each heading and
subheading.

Question 25

what was concluded about the study with immigrant mothers and us born mothers on receiving support

Answer 25

in spite of having fewer resources, immigrant mothers are less
likely than U.S.-born mothers to receive formal support (which includes access to public
assistance and private health insurance).

Question 26

what can explain why the differences between care for us born and immigrant mothers exist?

Answer 26

Further analyses could examine why these differences exist. Other variables that explain the
differences between these groups could be identified (such as educational attainment, social
support networks, or employment status). For a more detailed analysis of the relationships
between these variables, you need to consider some of the more complex techniques of
bivariate (two variable) analysis and statistical inference.