Question

1. in comparing the engagement levels of first-year statistics students. In a previous nation-wide study, engagement levels were found to be normally distributed, with µ=60.00, σ=10.00. The lecturer collects a convenience sample of 50 first-year students and finds that her students have a mean engagement level equal to 75.54.

What statistical procedure should be used, to test whether there is a significant mean difference in engagement levels between the lecturer’s first year students and the population average?

	a.	One sample Z-test.
	b.	Two sample Z-test.
	c.	Independent samples t-test.
	d.	One sample t-test.

2.

1. A university lecturer is interested in comparing the enthusiasm levels of mature age students versus recent high school leavers. To do this, he collects a random sample of 50 mature aged, and 50 high school aged students, and measures their enthusiasm levels. The following statistics were obtained:

Mature age students (M=72.86, SD=6.91).

High school leavers (M=61.44, SD=6.97).

What statistical procedure should be used, to test whether there is a significant mean difference in enthusiasm levels between mature aged and high school aged students?

	a.	Dependent samples t-test.
	b.	One sample t-test.
	c.	Independent samples t-test.
	d.	No statistical procedure is necessary. We can already see from the mean figures that mature aged students have a significantly greater mean.

3.

1. An organisational psychologist hypothesised that employee IQ levels of major Australian banks differ significantly to the general population. To test this, he performed a Z-test.

Listed below are the IQ scores of 20 random employees:106, 99, 104, 116,117,118,121,132,95,105,108,132,114,118,126,127,127,124,119,138.

If IQ scores are normally distributed, with µ=100, σ=15, what is the Z-statistic? Use these figures to calculate and select the correct the Z-statistic below.

	a.	5.16
	b.	3.35
	c.	1.15
	d.	17.30

4.

1. A clinical psychologist was interested in exploring if anxiety levels change after 3-months of Cognitive Behavioural Therapy. To explore this, she measured the anxiety levels of 20 clients using the Depression Anxiety and Stress Scale (DASS), at the start of treatment and then again 3-months later.

The following statistics were obtained:

Before treatment: M=10.40, SD=2.52, After treatment: M=9.25, SD=1.97, t=3.81.

What is the most appropriate way to report these results in APA format?

	a.	There is a significant mean difference in anxiety levels before treatment (M=10.40, SD=2.52) compared to after treatment (M=9.25, SD=1.97), t(20)=3.81, p>.05.
	b.	There is a significant mean difference in anxiety levels before treatment (M=10.40, SD=2.52) compared to after treatment (M=9.25, SD=1.97), t(20)=3.81, p<.05.
	c.	There is a significant mean difference in anxiety levels before treatment (M=10.40, SD=2.52) compared to after treatment (M=9.25, SD=1.97), t(19)=3.81, p>.05.
	d.	There is a significant mean difference in anxiety levels before treatment (M=10.40, SD=2.52) compared to after treatment (M=9.25, SD=1.97), t(19)=3.81, p<.05.

5.

1. A university lecturer is interested in comparing the enthusiasm levels of first-year statistics students. In a previous nation-wide study, enthusiasm levels of all university students were found to be normally distributed, with µ=70.00. The lecturer collects a random sample of 50 first-year students and the following statistics are obtained: M=55.73, SD=6.82.

What statistical procedure should be used, to test whether there is a significant mean difference in enthusiasm levels between the lecturer’s first year students and the population average?

	a.	One sample t-test.
	b.	Independent samples t-test.
	c.	Dependent samples t-test.
	d.	One sample Z-test.

Answer 1