Chapter 5

Question 1

What is the purpose of inferential stats

Answer 1

used to learn about the population from a sample

Question 2

two types of inferential stats

Answer 2

estimation
hypothesis testing

Question 3

Parameter

Answer 3

mathematical characteristics of populations

Question 4

A survey was conducted on 500 students from a population of 20,000 students at a university. It found that 74% of students were employed during the semester.
determine the
population
sample
statistic
parameter

Answer 4

population= 20,000 students
sample= 500 selected for interviews
statistic= 74% sample that held a job during the semester
parameter= % of all students in the population who held a job

Question 4

Statistics

Answer 4

mathematical characteristics of samples

Question 4

What is a random sample

Answer 4

every case in the population has the same chance of being selected

Question 4

What is a representative sample

Answer 4

a sample that reproduces important characteristics of the population

Question 4

What does EPSEM stand for and what does it mean

Answer 4

equal probability of election methods

Every element or case in the population must have an equal probability of being selected

Question 5

What is a non random sample

Answer 5

lack equal or known probability of selection

Question 6

sampling frame

Answer 6

the list of elements from which the sample will be selected

Question 7

Probability sample

Answer 7

a sample selected using a random process so that each element in the population has a known likelihood of being selected

Question 8

How to select a simple random sample

Answer 8

Number all the elements consecutively starting at 1.
Pick a sample size (n) from the total population (N).
Using a random number table or computer program to generate a list of random numbers.
The sample will be comprised of the cases whose element numbers match the randomly generated numbers.

Question 9

Sampling distribution

Answer 9

the theoretical probabilistic distribution of a statistic for all possible samples of a given size

Question 10

three distributions of inferential statics

Answer 10

sample
population
sampling distribution

Question 11

Example of the concept of sampling distribution

Answer 11

-draw a ample of ten people from a population of 100 multiple times
-calculate the mean age for each of these samples
-each sample will have a different outcome

Question 12

characteristics of a sampling distribution

Answer 12

-normal in shape
-mean equal to the population mean
-SD equal to the population SD
σ/n.

Question 13

As n becomes large…

Answer 13

the sampling distribution of a sample mean will approach normality with a mean and SD of σ/n.

Question 14

If n is to small…

Answer 14

you can’t apply statistics

Question 15

Importance of Central Limit Theorem

Answer 15

it removes the constraint of normality in the population

Question 16

What should a sample size generally be

Answer 16

100 or more

Question 17

The larger the sample size…

Answer 17

the more normal the curve gets

Question 18

Sampling distribution

Answer 18

distribution of a statistic for all possible outcomes of a certain sample size

Question 19

mean of the sampling distribution of means =

Answer 19

population mean

Question 20

standard deviation of sampling distribution=

Answer 20

population standard deviation divided by the square root on n

Question 21

systematic sample

Answer 21

every "i" the case in the sampling frame is selected

Question 22

stratified random sample

Answer 22

this type of sampling ensures that subgroups in the population are proportionally represented in the sample

Question 23

how to select a stratified random sample

Answer 23

divide into subgroups select a simple random sample or a systematic sample form each stratum If there are 80 students and 20 staff you wouldn't choose 5 from each you would take 2 staff and 8 student's

Question 24

multistage cluster sampling

Answer 24

select clusters then select subunits within the cluster Canadians provinces territories yukon, nunavut sask, alberta

Question 25

Example of a multi stage cluster sample

Answer 25

select a few provinces select a random subunit from each choose a city choose a street choose a house choose someone from the household

Question 26

3 qualities of a probability sample

Answer 26

representative allows for generalization from a sample to population inferential statistical tests sample means can be used to estimate population means

Question 27

convenience sampling

Answer 27

cases are included because they are readily available asking only people you see walk down the hallway

Question 28

snowball sampling

Answer 28

researcher makes contact with some individuals who in turn provide contacts for other participants Ask an addict a question and he sends you to another addict and they send you to another addict

Question 29

Quota sampling

Answer 29

collecting a specified number of cases in particular categories to match the proportion of cases in that category in the population you can learn from it but can't apply it to the general population

Question 30

the ______ determines whether the sample is a random sample

Answer 30

selection process

Question 31

The sales representatives employed by a large pharmaceutical firm are numbered sequentially. From those numbers, a computer program is used to select 30 random numbers. A sample of 30 reps whose numbers correspond to those randomly selected numbers is obtained.

Answer 31

Simple random sample

Question 32

A sampling method in which one of the first k individuals and then every kth individual thereafter is selected

Answer 32

Systematic random sample

Question 33

A sampling method in which groups naturally occurring in the population are randomly selected and a subsample of these cases within each selected unit is sampled

Answer 33

Cluster sample

Question 34

A sampling method in which some cases in the population, because of the way the sample is chosen, will not have a chance of being included in the sample

Answer 34

Non-probability sample

Question 35

A sampling method in which the population is first divided into a sublist based on a relevant trait, and a simple random sample is then taken from each group

Answer 35

Stratified random sample

Question 36

Representative

Answer 36

The quality a sample is said to have if it reproduces the major characteristics of the population from which it was drawn

Question 37

What is a simple, random sample

Answer 37

A method for choosing cases from a population in which every case has an equal chance of being included

Question 38

Standard error

Answer 38

The standard deviation of a sampling distribution