Tutor profile: Kaitlyn L.

Please explain the difference between top-down and bottom-up processes in sensation and perception.

Top-down processes are processes that are involved in identifying a stimulus by using the knowledge we already possess about the situation. This knowledge is based on past experiences and allows us to form expectations about what we ought to perceive. This also refers to information processing that begins in higher brain centers and proceeds to receptors. Comparatively bottom-up processes are processes that are involved in identifying a stimulus by analyzing the information available in the external stimulus. This also refers to information processing that begins at the receptor level and continues to higher brain centers.

Please describe the difference in construction between an a-line and a mermaid style wedding gown.

A wedding gown that is constructed with an a-line design will have a shape that is similar to the letter A. It will begin with a narrow corset that slowly transitions to a fuller skirt once it is past the waistline. An a-line gown will not be constructed with harsh edges to create a dramatic silhouette but rather with soft edges that permit a full-skirt effect that gradually increases from waistline to the train. Comparatively a mermaid style wedding gown will be constructed so that the bodice, waist, and top portion of the skirt will be tight and lay very close to the person's body when wearing the gown. Additionally, the key to a mermaid style gown is that at the bottom of the skirt typically tulle is built up underneath the gown in layers to create an effect where only the bottom part of the skirt will create a dramatic line away from the body. This permits the bottom portion of the skirt to fan out in a dramatic fashion.

Explain average deviation and standard deviation by describing how they differ and why the difference is important in research design and analysis.

The average deviation is the set of scores calculated by computing the mean and then the specific distances between each score in that mean. The average deviation always equals zero. Comparatively the standard deviation is the statistic that measures the dispersion of the dataset relative to the mean and it is calculated as the square root of variance- this provides us with a number that is not zero. The difference between these two concepts is important because it is the numeric value in the standard deviation that tells us the average amount of variability in the data set, essentially saying how far each score is from the mean which cannot be told to us by the average deviations zero. Thus in research design and analysis this difference is valuable because it lets us know we should use the standard deviation to inform us about the spread of our data not the average deviation.