Question

Experiment 3

Part 1:

Dr. Schwartz wanted to examine the hypothesis that smelling peppermint affects exercise intensity, so she used random assignment in her first experiment on this topic. The peppermint group exercised in a room in which a peppermint scent was released once each minute, while the no peppermint group exercised in an unscented room. She measured the distance participants cycled in 20 minutes on indoor bicycles. After she completed that first experiment, Dr. Schwartz realized that perhaps her results in the first experiment could be attributable to the failure of random assignment to balance the weight of participants in the two groups. Thinking that this alternative explanation might explain why she got nonsignificant results in the first experiment, she decided to match participants on weight. She randomly assigned the two heaviest participants to either the peppermint or no peppermint conditions by flipping a coin, and then randomly assigned the next two heaviest participants, and so on.

Using the data shown below, conduct the appropriate statistical test in SPSS to determine whether there is a statistically significant difference between how far the participants in the peppermint condition rode vs. how far participants in the no peppermint condition rode.

	Peppermint	No Peppermint
Pair 1	2.3	2.0
Pair 2	2.7	3.1
Pair 3	3.4	3.5
Pair 4	3.0	1.9

1. What is the design of this experiment?

Single sample

Between subjects

Within subjects

2. What kind of samples are being used in this experiment?

Matched samples

Dependent samples

The samples are both matched and dependent

Same sample

3. What is the M for the Peppermint group? (answer to 2 decimal places)

4. What is the M for the No Peppermint group? (answer to 2 decimal places)

5. What is the standard deviation for the Peppermint group? (answer to 2 decimal places)

6. What is the standard deviation for the No Peppermint group?(answer to 2 decimal places)

7. What is the value of t based on the SPSS output?(answer to 2 decimal places)

8. What is the p value you see in the SPSS output? (answer to 3 decimal places)

9. Write a conclusion based on the output you reported in the questions immediately above. Be sure to report the appropriate statistic in APA style.

From the following list of words and symbols, create your APA-style conclusion. Please also use any necessary numbers and punctuation (they are NOT provided in this list), and please include spaces around symbols as needed.

Do not use any words that are not in this list. Use as few words as possible to convey the necessary information. You will NOT use all the words provided.

A

Cycle

Cycled

Did

Distance

Farther

Less

Longer

More

Not

Of

Participants

Peppermint

Same

Smell

Smelled

Than

The

They

When

Who

p

M

t

( )

=   >   <   ≤ ≥

Part 2:

Next, Dr. Schwartz wanted to see what would happen if she had each participant cycle once in the peppermint condition and once in the no-peppermint condition. Participants were counterbalanced, with half of them cycling on Day 1 in the peppermint condition, and the other half cycling on Day 1 in the no peppermint condition. On Day 2, one week later, the participants cycled in the condition they had not yet completed.

Using the data shown below, conduct the appropriate statistical test in SPSS to determine whether there is a statistically significant difference between how far the participants rode in 20 minutes when in the peppermint condition vs. when they were in the no peppermint condition.

	Peppermint	No Peppermint
Participant 1	2.5	2.0
Participant 2	3.8	3.1
Participant 3	3.8	3.3
Participant 4	3.1	2.6
Participant 5	2.7	2.0
Participant 6	2.8	2.2
Participant 7	2.9	2.8
Participant 8	3.5	3.1

10. What is the design of this experiment?

Between subjects

Single sample

Within subjects

11. What kind of samples are being used in this experiment?

Dependent samples

Matched samples

Same samples

12. What is the M for the Peppermint condition? (answer to 2 decimal places)

13. What is the M for the No Peppermint condition? (answer to 2 decimal places)

14. What is the standard deviation for the Peppermint condition? (answer to 2 decimal places)

15. What is the standard deviation for the No Peppermint condition?(answer to 2 decimal places)

16. What is the value of t you found in the SPSS output?

17. What is the value of p shown in the SPSS output? (Give the EXACT number shown in the actual SPSS output)

18. What is correct way to write the value of p in APA style based on what you answered in the previous question?

19. Write a conclusion based on the output you reported in the questions immediately above. Be sure to report the appropriate statistic in APA style.

You can (but are not required to) use the following list of words and symbols to create your APA-style conclusion. Please also use any necessary numbers and punctuation (they are NOT provided in this list), and include spaces as required around symbols.

Use as few words as possible to convey the necessary information. You will NOT use all the words provided.

A

Cycle

Cycled

Did

Distance

Farther

Less

Longer

More

Not

Of

Participants

Peppermint

Same

Smell

Smelled

Than

The

They

When

Who

p

M

t

( )

=   >   <   ≤ ≥

Answer 1

Part 1:

Using the data shown below, conduct the appropriate statistical test in SPSS to determine whether there is a statistically significant difference between how far the participants in the peppermint condition rode vs. how far participants in the no peppermint condition rode.

	Peppermint	No Peppermint
Pair 1	2.3	2.0
Pair 2	2.7	3.1
Pair 3	3.4	3.5
Pair 4	3.0	1.9

1. What is the design of this experiment?

Within subjects

2. What kind of samples are being used in this experiment?

Matched samples

SPSS output

Paired Samples Statistics
		Mean	N	Std. Deviation	Std. Error Mean
Pair 1	Peppermint	2.8500	4	0.46547	0.23274
	No Peppermint	2.6250	4	0.79739	0.39870

Paired Samples Test
		Paired Differences					t	df	Sig. (2-tailed)
		Mean	Std. Deviation	Std. Error Mean	95% Confidence Interval of the Difference
					Lower	Upper
Pair 1	Peppermint - No Peppermint	0.22500	0.65000	0.32500	-0.80930	1.25930	0.692	3	0.539

3. What is the M for the Peppermint group? (answer to 2 decimal places) 2.85
4. What is the M for the No Peppermint group? (answer to 2 decimal places) 2.63
5. What is the standard deviation for the Peppermint group? (answer to 2 decimal places) 0.47
6. What is the standard deviation for the No Peppermint group?(answer to 2 decimal places) 0.80
7. What is the value of t based on the SPSS output?(answer to 2 decimal places)0.69
8. What is the p value you see in the SPSS output? (answer to 3 decimal places) 0.539
9. Write a conclusion based on the output you reported in the questions immediately above. Be sure to report the appropriate statistic in APA style.

From the following list of words and symbols, create your APA-style conclusion. Please also use any necessary numbers and punctuation (they are NOT provided in this list), and please include spaces around symbols as needed.

The participants with the peppermint smelled rode the cycle same distance as the no peppermint smelled , t(3)=0.69, p=0.539.

Part 2:

10. What is the design of this experiment?

Within subjects

11. What kind of samples are being used in this experiment?

Same samples

SPSS output

Paired Samples Statistics
		Mean	N	Std. Deviation	Std. Error Mean
Pair 1	Peppermint	3.1375	8	0.50409	0.17822
	No Peppermint	2.6375	8	0.52082	0.18414

Paired Samples Test
		Paired Differences					t	df	Sig. (2-tailed)
		Mean	Std. Deviation	Std. Error Mean	95% Confidence Interval of the Difference
					Lower	Upper
Pair 1	Peppermint - No Peppermint	0.50000	0.19272	0.06814	0.33888	0.66112	7.338	7	0.000

12. What is the M for the Peppermint condition? (answer to 2 decimal places) 3.14
13. What is the M for the No Peppermint condition? (answer to 2 decimal places)2.64
14. What is the standard deviation for the Peppermint condition? (answer to 2 decimal places)0.50
15. What is the standard deviation for the No Peppermint condition?(answer to 2 decimal places)0.52
16. What is the value of t you found in the SPSS output? 7.338
17. What is the value of p shown in the SPSS output? (Give the EXACT number shown in the actual SPSS output) 0.000
18. What is correct way to write the value of p in APA style based on what you answered in the previous question? P<0.001
19. Write a conclusion based on the output you reported in the questions immediately above. Be sure to report the appropriate statistic in APA style.

The participants with the peppermint smelled rode the cycle   distance longer than the no peppermint smelled , t(7)=7.34, p<0.001.