Lab 1

Question 1

Step 1: Ask a Question

What is an indepent variable?

Answer 1

The essential componenet of the phenomenon that is manipulated by the investigator

Question 2

Step 1: Ask a Question

What is a dependent variable?

Answer 2

The response to the manipulation.

Question 3

Step 1: Ask a Question

What is the observed variable?

Answer 3

The variable we are interested in studying to see whether it has an effect on the dependent variable, however the observed variable cannot be experimentally manipulated.

It involves mutually exclusize groupings that can be identified by name and may or may not have an order.

Question 4

Step 1: Ask a Question

What is the comparator?

Answer 4

A group or condition that provides a point of comparison so the research knows if the independent/observed variable influenced the dependent variable.

Question 5

Step 1: Ask a Question

What is an experimental study?

Answer 5

In an experimental study, the comparator will typically be a baseline condition, a control group, or a control condition.

Question 6

Step 4: Test the hypothesis

What is a descriptive study?

Answer 6

Descriptive studies involve collecting infromation without any manipulation of the subjects.

- there is no indp variable

Question 7

What are the 7 steps of the scientific method?

Answer 7

1. Ask a question
2. Perform background research
3. Construct a hypothesis
4. Test the hypothesis
5. Analyze the data and draw a conclusion
6. Reflect on the results
7. Communicate the results

Question 8

Step 3: Construct a hypothesis

What is a hypothesis?

What are the different types?

Answer 8

The hypothesis is the predicted result of the experiment and expected answer to the research question.

1. Directional hypothesis: proposes the dependent variable will incr or decr when the indp variable is changed.
2. Non-direction hypothesis: proposes the 2 variables are related

Question 9

Step 3: Construct a hypothesis

What are the 4 components of a well-constructed hypothesis?

Answer 9

1. Indp variable being manipulated
2. Depd variable being measured
3. Comparartor group/condition
4. Population being studied, including key subject characteristics

Question 10

Step 4: Test the hypothesis

What is an experimental study?

Answer 10

An intervention of treatment is intentionally introduced and a result or outcome is observed.

Question 11

Step 4: Test the hypothesis

What is a case study?

Descriptive

Answer 11

1-2 instances of an observed phenomenon

Question 12

Step 4: Test the hypothesis

What is a cross-sectional study?

Descriptive

Answer 12

A random subset of a population is sampled to observe the occurrence of a phenomenon

Ex: samping incoming CU freshman to determine what percentage are smokers

Question 13

Step 4: Test the hypothesis

What is a longitudinal study?

Descriptive

Answer 13

A group of subjects is followed over time to observe how a variable changes

Question 14

Step 4: Test the hypothesis

What is a retrospective study?

Descriptive

Answer 14

A search is made for a relationship between a current phenomenon and another that occured in the past to examine whether exposure to a suspected risk or protective factor led to an outcome

Question 15

Step 4: Test the hypothesis

What is a randomized, controlled study?

Experimental

Answer 15

Subjects are randomly assigned to either an experimental OR control group

Question 16

Step 4: Test the hypothesis

What is a pre/post study?

Experimental

Answer 16

Depd variable is measured in each subject before the manipulation (baseline), and then measured again one time after the manipulation

Question 17

Step 4: Test the hypothesis

What is a time series study?

Experimental

Answer 17

A depd variable is measured in each subject before the manipulation (baseline), and then measured again multiple times after the manipulation to observe how the depd variable changes over time

Question 18

Step 4: Test the hypothesis

What is a crossover study?

Experimental

Answer 18

Subjects are divided into different groups, with each group receiving all treatments, but in a different order

Question 19

Step 5: Analyze the data and draw a conclusion

What is a null hypothesis?

What happens if there is significance difference?

Answer 19

If you are testing the null hypothesis than the results being compared are NOT different. If you find a statistically significant difference between the results being compared, you reject the null hypothesis.

Meaning the manipulation does appear to influence the depd variable.

Question 20

Step 5: Analyze the data and draw a conclusion

What is the p-value?

What does a small p-value indicate?

Answer 20

The p-value indicates the probablity the results occured by chance alone and are not different.

A small p-value (smaller than alpha, i.e. p<0.05) means the null hypothesis is rejected.

Question 21

Step 5: Analyze the data and draw a conclusion

What is a chi-square test?

Answer 21

Used to compare whether the observed frequency of a characteristic in a sample matches the expected distribution in another group.

Question 22

Step 5: Analyze the data and draw a conclusion

What is a t-test?

What are the 2 different types?

Answer 22

A t-test compares two means.

1. Dependent (paired) t-test: used to compare mean values from the same subjects are tested more than once or when some other nautral pairing exsits between the measurements
2. Independent t-test: used to compare mean valued from two groups that are not related to each other

Question 23

Step 5: Analyze the data and draw a conclusion

What is an ANOVA test?

What are the 2 different types?

Answer 23

Analysis of Variance (ANOVA) compres more than 2 means.

1. Repeated measures ANOVA: used when the mean values are from the same subject evaluated at multiple points
2. One-way ANOVA: used when comparingthe mean values from multiple unrelated groups for a single variable.

Question 24

Step 5: Analyze the data and draw a conclusion

On a graph where are the indp. and depd. variable placed?

Answer 24

The indp variable is placed on the X-axis and the depd. variable is placed on the Y-axis.

Question 25

Step 6: Reflect on the results

What are the 2 different types of limitations?

Answer 25

1. Methodological: due to actual methodology
2. Physiological: due to phsyiological factors of subjects

Question 26

Give an example of hypothesis using average hematocrit levels between males and females.

Answer 26

Hematocrit levels(%) in males will be higher as compared to hematocrit levels (%) in female in healthy college-aged adults living at similar altitudes.

Question 27

Give an example of a figure caption using average hematocrit between male and female.

Answer 27

Table 1. Average hematocrit (%) values for male (n=8) and female (n=12) Physiology Lab students living in the Boulder area. Data represent average + SD. An independent t-test was used to compare the means with an alpha level of 0.05. * indicates statistical significance at p<alpha as compared to females.