COM3000 Exam 3 Latest
Update
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:
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
Research H1: μmale¹ DOESNT EQUAL μfemale•
Null H0: μmale= μfemale
Directional Hypothesis
Examples
Research & Null -Answer Male students interrupt more frequently than do female
students
ResearchH1: μmale> μfemale•
Update
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:
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
Research H1: μmale¹ DOESNT EQUAL μfemale•
Null H0: μmale= μfemale
Directional Hypothesis
Examples
Research & Null -Answer Male students interrupt more frequently than do female
students
ResearchH1: μmale> μfemale•
