©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
Exam 3 COM3000 Questions With Correct
Answers
What is the purpose of inferential statistics - answer✔Estimation: generalizing from sample to
population (statistics to parameter)
Assumes:
-Normal distribution of variable(s) in population
-Random sampling
What is the purpose of significance testing - answer✔identifying the likelihood of chance
relationships between variables or chance differences between groups (95%)
Research Hypothesis: - answer✔predicts relationship between variables or difference between
groups (H1)
Null Hypothesis: - answer✔predicts NO relationship between variables or difference between
groups (H0)
-We want to REJECT the null
Which of the two (research or null hypothesis) do you actually test when analyzing your data -
answer✔]we always begin by assuming that the null hypothesis is true and there is no
difference between the groups or relationship between the variables—statistics always test the
null
What does it mean to "Reject the null?" In what circumstances is this the right decision to
make? - answer✔if there is a difference or relationship. Your research hypothesis has been
supported
What does it mean to "Retain the null"? In what circumstances is this the right decision to
make? - answer✔if there is not a difference or relationship. Your research hypothesis has not
been supported
Research Hypothesis:
1|Page
, ©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
Non-directional - answer✔States that a relationship between variables exists; but does not
specify the nature of the difference or relationship (two-tailed)
H1: μ1¹ DOES NOT EQUAL μ2
Translation: The research hypothesis is that the population average of group 1 is not equal to
the population average of group 2
Research Hypothesis:
Directional - answer✔-States that a difference between groups exists and specifies the nature
of the difference (one-tailed)
H1: μ1> μ2 or H1: μ1< μ2
Translation: the research hypothesis is that the population average of group 1 is greater than
the population average of group 2
Null Hypothesis:
non-directional - answer✔States that there is no difference between the groups•
H0: μ1= μ2
Translation: The null hypothesis is that the population average of group 1 is equal to the
population average of group
Null Hypothesis:
directional - answer✔-Opposes the difference between groups stated in the research
hypothesis
H1: μ1 > μ2•
H0: μ1 <_ μ2
H1: μ1< μ2
H0: μ1 >_ μ2
Translation: The null hypothesis is that the population average of group 1 is less than or equal
to the population average of group 2.
Non-directional Hypothesis Examples
Research & Null - answer✔Male and female students differ in terms of their number of
conversational interruptions
2|Page
11/16/2024 10:16 AM
Exam 3 COM3000 Questions With Correct
Answers
What is the purpose of inferential statistics - answer✔Estimation: generalizing from sample to
population (statistics to parameter)
Assumes:
-Normal distribution of variable(s) in population
-Random sampling
What is the purpose of significance testing - answer✔identifying the likelihood of chance
relationships between variables or chance differences between groups (95%)
Research Hypothesis: - answer✔predicts relationship between variables or difference between
groups (H1)
Null Hypothesis: - answer✔predicts NO relationship between variables or difference between
groups (H0)
-We want to REJECT the null
Which of the two (research or null hypothesis) do you actually test when analyzing your data -
answer✔]we always begin by assuming that the null hypothesis is true and there is no
difference between the groups or relationship between the variables—statistics always test the
null
What does it mean to "Reject the null?" In what circumstances is this the right decision to
make? - answer✔if there is a difference or relationship. Your research hypothesis has been
supported
What does it mean to "Retain the null"? In what circumstances is this the right decision to
make? - answer✔if there is not a difference or relationship. Your research hypothesis has not
been supported
Research Hypothesis:
1|Page
, ©BRIGHTSTARS EXAM SOLUTIONS
11/16/2024 10:16 AM
Non-directional - answer✔States that a relationship between variables exists; but does not
specify the nature of the difference or relationship (two-tailed)
H1: μ1¹ DOES NOT EQUAL μ2
Translation: The research hypothesis is that the population average of group 1 is not equal to
the population average of group 2
Research Hypothesis:
Directional - answer✔-States that a difference between groups exists and specifies the nature
of the difference (one-tailed)
H1: μ1> μ2 or H1: μ1< μ2
Translation: the research hypothesis is that the population average of group 1 is greater than
the population average of group 2
Null Hypothesis:
non-directional - answer✔States that there is no difference between the groups•
H0: μ1= μ2
Translation: The null hypothesis is that the population average of group 1 is equal to the
population average of group
Null Hypothesis:
directional - answer✔-Opposes the difference between groups stated in the research
hypothesis
H1: μ1 > μ2•
H0: μ1 <_ μ2
H1: μ1< μ2
H0: μ1 >_ μ2
Translation: The null hypothesis is that the population average of group 1 is less than or equal
to the population average of group 2.
Non-directional Hypothesis Examples
Research & Null - answer✔Male and female students differ in terms of their number of
conversational interruptions
2|Page
