Basic Definitions, Measures of Central Tendency, Quartiles (1)

Question 1

The study that utilizes a variety of methods for collecting, displaying, analyzing, interpreting and drawing conclusions from a given set of data

Answer 1

Statistics

Question 2

Main group of subjects in a study

Answer 2

Population

Question 3

A subset of the main group of the study

Answer 3

Sample

Question 4

A city council member wanted to know how her constituents felt about a planned rezoning. She randomly selected 75 names from the city phone directory and conducted a phone survey.

Identify the population and sample in this setting.

a. The population is everyone listed in the city phone directory; the sample is the 75 people selected.

b. The population is residents of the city; the sample is the registered voters in the city.

c. The population is registered voters in the city; the sample is everyone listed in the city phone directory.

Answer 4

a.

Question 5

Lucio wants to know whether the food he serves in his restaurant is within a safe range of temperatures. He randomly selects 70 entrees and measures their temperatures just before he serves them to his customers.

Identify the population and sample in this setting.

a, The population is all of the hot entrees Lucio serves; the sample is the entrees that are a safe temperature.

b. The population is the 70 selected entrees; the sample is the entrees that are a safe temperature.

c. The population is all of the entrees Lucio serves; the sample is the 70 selected entrees.

Answer 5

c.

Question 6

Define measurement

Answer 6

The attribute or number for each member of a sample or population. The measurement of the collected sample elements are called sample data.

Question 7

What is the difference between Inferential and Descriptive Statistics?

Answer 7

Descriptive - describes, displays, and organizes properties of data (i.e. using the frequency distribution table, charts, graphs, etc.)
Inferential - draws conclusion about a population based on sample information

Question 8

Measurements consisting of the attributes, labels, or other non-numerical characteristics of the elements

Answer 8

Qualitative data

Question 9

Numerical measurements arising from a numerical scale

Answer 9

Quantitative data

Question 10

What is the most important concept in statistics?

Answer 10

The relationship between a population and the sample drawn from the population

Question 11

Marco is conducting an experiment on training certain breeds of dogs. He wants to know how long, on average, it would take to teach a Labrador to fetch an object. He gets a group of dogs to conduct his experiment. 5 of the dogs are Labradors and 3 of the dogs are Dalmatians. What is the population and sample in this experiment?

Answer 11

Population: All Labradors
Sample: 8 dogs that Marco gathered

Question 12

What is a metric?

Answer 12

Population - quantitative measurement of something for the whole population (e.g. Average Spending of LSGH SHS students during Valentine’s Day; the metric here is the average spending of the entire LSGH SHS student population)
Sample - quantitative measurement of something for samples (e.g. Average Spending of 20 of my LSGH SHS students during Valentine’s Day; the metric here is the average spending of the 20 LSGH SHS students)

Question 13

What is the difference between parameter and statistic?

Answer 13

Parameter - Number/characteristic used to describe the whole population
Statistic - Number/characteristic used to describe the sample

Question 14

What is the fundamental concept in inferential statistics?

Answer 14

The distinction between a population together with its parameters, and a sample together with its statistics

Question 15

What are the conditions in which a data set will have no mode

Answer 15

• All distinct values have the same frequency
• The data set contains only one distinct value repeated many times (e.g. 3, 3, 3, 3, 3, and so on)

Question 16

They answer the question “Where is the center of the data set?

Answer 16

Measures of Central Tendency (mean, median, mode)

Question 17

This graphical representation indicates the nature of the data set

Answer 17

Relative frequency histogram

Question 18

It refers to the data value’s significance in a data set depending on how it compares to the other values in the data set

Answer 18

Relative position

Question 19

Measures that divide a data set points into four parts

Answer 19

Quartiles

Question 20

What does Q1, Q2, & Q3 signify?

Answer 20

Q1 (lower quartile)- lowest 25% from the highest 75%
Q2 (median) - 50/50
Q3 (upper quartile) - highest 25% from the lowest 75%

Question 21

What are the steps in computing for the quartile INDICES?

Answer 21

1. Arrange the measures in ascending order
2. Q1 = 25% * n (where n = size of the sample). If the result is a decimal, round it up to the nearest whole number. Otherwise, Q1 is just the average of the (25% * n) & (25% * n) + 1 terms.
3. Q2 = 50% * n. If the result is a decimal, round it up to the nearest whole number. Otherwise, Q2 is just the average of the (50% * n) & (50% * n) + 1 terms.
4. Q3 = 75% * n. If the result is a decimal, round it up to the nearest whole number. Otherwise, Q3 is just the average of the (75% * n) & (75% * n) + 1 terms.

Question 22

When the study involves the whole population, it is called a [BLANK]

Answer 22

CENSUS

Question 23

Determine whether the statement describes descriptive statistics or inferential statistics.

1. The average age of the students in a particular history class is 19 years.
2. There is a relationship between smoking cigarettes and getting emphysema.
3. From past figures, it is predicted that 40% of the registered voters in California will vote in the next primary.
4. The chances of winning the Maryland Lottery are one chance in 22 million.

Answer 23

1. DESCRIPTIVE
2. INFERENTIAL
3. INFERENTIAL
4. INFERENTIAL

Question 24

An inspector conducts an evaluation (environment is of appropriate / comfortable temperature, humidity, and ventilation; doors can be opened / unlocked from inside; etc.) on a randomly selected group of eight classrooms at an elementary school. What is the population and sample?

Answer 24

The population is all classrooms in the elementary school; the sample consists of the eight classrooms.

Question 25

Identify each of the following measures as either quantitative or qualitative.

The genders of the first 40 newborns in a hospital in one year

Answer 25

QUALITATIVE

Question 26

Identify each of the following measures as either quantitative or qualitative.

The natural hair color of 20 randomly selected fashion models

Answer 26

QUALITATIVE

Question 27

Identify each of the following measures as either quantitative or qualitative.

The political affiliations of 500 randomly selected voters

Answer 27

QUALITATIVE

Question 28

Identify each of the following measures as either quantitative or qualitative.

The fuel economy (in miles per gallon) of 20 new cars purchased last month

Answer 28

QUANTITATIVE

Question 29

Identify each of the following measures as either quantitative or qualitative.

The ages of 20 randomly selected fashion models

Answer 29

QUANTITATIVE

Question 30

A mean could be a:

Answer 30

Parameter or a statistic

Question 31

In a survey, people are asked: “Which brand of toothpaste do you prefer?” The data gathered from this question would be what type of data?

Answer 31

Categorical

Question 32

The owners of a sports stadium wanted to predict what additional refreshment options would sell well. They selected 90 seat numbers at random and surveyed the occupants of those seats. What is the population and sample?

Answer 32

Population: occupants of all seats in the sports stadium
Sample: occupants of the 90 selected seats

Question 33

A student is gathering data on the driving experiences of other college students. One of the variables measured is the type of car the student drives. These data are coded using the following method: 1 = subcompact, 2 = compact, 3 = standard size, 4 = full size, 5 = premium, 6 = mini van, 7 = SUV, 8 = truck. What type of variable is this?

Answer 33

Categorical