HSCI 190 Module 4 Homework:
Exploring Statistical Tests and
Applications Comprehensive Study
Guide!!!
, Module 4 Problems
Part 1 - Consolidating Concepts
1. A one-sample t-test would be used in a situation where the standard deviation of the
population is not known and/or if the population size is less than 30. The one-sample
t-test would be used with a sample standard deviation to predict the variance. A
one-sample z-test would typically be used in a situation where the standard deviation of
the population is known.
2. Dependent t-tests compare 2 dependent or paired groups while independent t-tests
compare 2 independent or unpaired groups. In dependent t-tests, the observations in
one group have a corresponding observation in a second group. An example of a
dependent t-test would be a study evaluating a group of smokers’ daily cigarette
consumption before and after an 8 week counselling program. An example of an
independent t-test would be a study documenting the height of first-year university
students in Canada versus the height of first-year university students in the United
States.
3. Parametric tests make assumptions about the population while non-parametric tests do
not make the same assumptions. Non-parametric tests are considered
“distribution-free” and can be used with any population. Parametric tests require scale
measurement, normally distributed data while non-parametric tests can use scale or
ordinal data and normal distribution is not a requirement.
4. The properties of a chi square distribution are:
➢ Right-skewed.
➢ Positive values only as a squared value.
➢ The mean of a chi square distribution is = to its df (degrees of freedom).
➢ Variance is = to its df multiplied by 2.
➢ If there are at least 2 df, the mode of the chi square distribution is = to the df
minus 2.
➢ Square of the normal distribution.
➢ Df defines the shape of the chi square distribution.
Part 2 - Application Using Statistical Software
Problem #1
a) Null hypothesis: There are no differences in the proportion of male vs female mice
confirmed with IBD.
Exploring Statistical Tests and
Applications Comprehensive Study
Guide!!!
, Module 4 Problems
Part 1 - Consolidating Concepts
1. A one-sample t-test would be used in a situation where the standard deviation of the
population is not known and/or if the population size is less than 30. The one-sample
t-test would be used with a sample standard deviation to predict the variance. A
one-sample z-test would typically be used in a situation where the standard deviation of
the population is known.
2. Dependent t-tests compare 2 dependent or paired groups while independent t-tests
compare 2 independent or unpaired groups. In dependent t-tests, the observations in
one group have a corresponding observation in a second group. An example of a
dependent t-test would be a study evaluating a group of smokers’ daily cigarette
consumption before and after an 8 week counselling program. An example of an
independent t-test would be a study documenting the height of first-year university
students in Canada versus the height of first-year university students in the United
States.
3. Parametric tests make assumptions about the population while non-parametric tests do
not make the same assumptions. Non-parametric tests are considered
“distribution-free” and can be used with any population. Parametric tests require scale
measurement, normally distributed data while non-parametric tests can use scale or
ordinal data and normal distribution is not a requirement.
4. The properties of a chi square distribution are:
➢ Right-skewed.
➢ Positive values only as a squared value.
➢ The mean of a chi square distribution is = to its df (degrees of freedom).
➢ Variance is = to its df multiplied by 2.
➢ If there are at least 2 df, the mode of the chi square distribution is = to the df
minus 2.
➢ Square of the normal distribution.
➢ Df defines the shape of the chi square distribution.
Part 2 - Application Using Statistical Software
Problem #1
a) Null hypothesis: There are no differences in the proportion of male vs female mice
confirmed with IBD.
