Question

Karen

wants to study the effect of cardiovascular exercises on first

year UTSC students’ resting heart rate. Karen plans to select 2 groups

of students, 30 per group. The “exercise” group will partake in group

cycling around the campus 3 times a week, for 4 weeks. The other,

“

no

-

exercise

” group, will not.

Students’ resting heartrate will be

measured in beats per minute, before and after the 4 weeks period

.

•

What

is Karen’s population of interest?

•

What

is the

IV?

What type of data is the DV?

•

What

is the

DV? What

type of data is the DV?

•

Which

measurement scale is used in the

DV

?

•

Is this a between

-

subjects or within

-

subjects design? How could we

change the design of the experiment?

•

How

can Karen ensure that her study has external & internal

validity?

•

What are some nuisance/confound variables that you can think of?

Answer 1

(a)

Population of interest:

First year UTSC students

(b)

Independent variable:

cardiovascular exercises

Type of data:

Nominal

(c)

Dependent variable:

resting heart rate

Type of variable:

Ratio

(d)

between subjects design

(e)

We could change the design of experiment from the present between subjects design to within subjects design by combining both groups into a single group and making all participants undergo cardiovascular exercises.

(f)

Karen can ensure external validity by ensuring that the same can be applied to the entire student community at large.

Karen can ensure internal validity by voiding possible confounding variables.

(g)

Some nuisance/ confound variable that we can think of is the inherent heart rate of each student irrespective of cardiovascular exercises is not the same.