A disadvantage to interview research methods, on the other hand, include the potential for bias based on the respondents' desire to please the researcher, who will necessarily be directly involved in the research process. 7)

In the One-Group Pretest-Posttest experimental design, a single group of subjects is given a test that measures a certain variable or variables, then is exposed to the experimental condition, and then is tested again to measure the effects of this exposure. While this might seem valid, there are several threats to internal validity facing this design. Other intervening events could affect posttest scores, the simple passing of time could have an effect, different test conditions could lead to different results, and selection biases could also influence outcomes.

8)

There are a number of factors that influence the sample size needed for a given piece of research. The desired confidence level of the research outcomes, the level of precision necessary in the data collection and analysis, and the degree of variability that exists in the population at large can all have an effect on the needed sample size. For greater levels of precision and confidence, larger sample sizes will be needed. Greater levels of variability in the general population would also require a larger sample size, in order to ensure that the population is well and accurately represented across all of its variability.

9)

Random sampling...

This step is taken at the very beginning of research to ensure that the sample population is representative of the general population. Random assignment refers to randomly placing selected subjects into various research groups. This step is taken in order to ensure that no bias is created in different experimental and/or control groups, so that each group is comprised of similar proportions and demographics.
10)

a. The required level of measurement for both data sets is the interval level or scale.

b. Null hypothesis: There is no correlation between previous experience and current salary.

Two tailed (alternative) hypothesis: Current salary is dependent on previous

experience, with more experience leading to a higher than average salary and less experience leading to lower than average compensation

c. Rejection level: p < .05

d. The value of Pearson's r is positive, suggesting a direct relationship if any (i.e. when one variable increases, so does the other), but the fact that this value is so close to zero suggests that there is not a correlation between these two variables. The very high value of the significance suggests that these results are not statistically significant, which would have more bearing had a correlation been established by Pearson's r. Given these results, it is not possible to reject the null hypothesis.