As described in our text longitudinal strengths allows the study of several alike patterns, and participants with individual differences in their development. With longitude studies it also permits investigators to see the relationships between later and earlier life events in behavior. As for weakness in longitudinal studies, due to age related changes some of the subjects may drop out, cohort and practice effects. Next we have sequntial, this is when the investigator combines several longitudinal and cross sectional studies, this is also called sequences. With this study the investigator will study individuals that are the same age, but at different times or year. The investigator may also study individuals of different age groups, but during the same time or during the same year. Some of the strengths of Sequential is that it allows the investigator to exam both longitudinal as well as cross sectional. With sequential it allows tracking of age related changes, much better than the longitudinal. Then we have some of the weaknesses of sequential, it can have several of the same issues as the other two, but the way it is designed helps identify difficulties much better. This brings us to Cross Sectional. With cross sectional the investigators will study several groups of individuals all of different ages, but they will be studied at the same point in time. Some of the strengths of cross sectional is that it’s more effectual than longitudinal, and it’s not tormented with individuals dropping out for whatever reason, and practice effects. Now we come to the weaknesses of cross sectional, it does not allow the study of individual inclination, also age differences may be misleading or a false account or impression due to cohort effect. Naturalistic Observation is when a researcher is observing an individual’s behavior as natural as possible, but this is not done in a controlled environment. We also have Self reports, with