Bob's Experiment

MKTG 465 – W2018

INDIVIDUAL ASSIGNMENT 1

1. Schema:

[pic 1][pic 2][pic 3][pic 4][pic 5]

1. Measurement properties:

• Independent variable (Atmosphere of the store) → Interval[pic 6][pic 7][pic 8][pic 9][pic 10][pic 11][pic 12][pic 13][pic 14]
• Dependent variable (Retail sales) → Ratio

1. Bob’s experimental design:

EG1: X1 (F,D)   O1[pic 15]

EG2: X2 (F,C)   O2

EG3: X3 (S,D)   O3

EG4: X4 (S,C)   O4

1. Possible contamination on experimental design due to following variables:

1. Maturation (MA): No. This extraneous variable cannot be controlled with this experimental design because it needs the presence of a pre-test measurement to perceive differences in prior and later observation by comparing both attitudes. So, it is impossible to see the maturation effect with this experimental design.

1. Main Testing Effect (MT): No. It cannot contaminate the comparison of experimental groups since MT effect conditions are not met with this experimental design. As, MA effect, it needs a pre-measurement observation to compare the effect to the exposure with the post-test results. As we do not have this included in the design of the experiment, MT cannot exist here.

1. Order Effect: No. With this type of experimental design, we cannot observe any order effect because the respondents in the different treatment groups are only experience one exposure. Without multiple exposures, order effect has no existence in this experiment. Moreover, Bob removes the respondents who went to the store multiple times, making the comparison of the order impossible.

1. Criteria for causality:

1. Time of occurrence → Bob’s experiment meets this condition because X (Atmosphere of the store) precedes the occurrence of Y (Retail sales).

1. Concomitant variation → Bob’s experiment of modifying shopping environment entirely cannot explain the variation between the different average expenditures per customer on each day. Even though both variables vary together, the extent to which they vary and why they do it, cannot be explained in a predicted way with this experiment hypothesis.

1. Elimination of alternate explanations → The experiment only considers the different lighting and music for affecting the amount spent by customers. There are many more reasons inside the store atmosphere (number of customers in the store, cleanness, employee caring, availability of products…) that are not specified in the experiment and may differ between days. Also, there are outside store’s atmosphere conditions that affect respondent’s propensity to buy such as availability of time, quantity of products needed, etc. They are not considered and may be other variables that explain the differences of customer’s shopping behavior.

Concluding, Bob’s experiment does not meet all the conditions for being considered a causal research and so, cannot conclude that the atmosphere of the store is the cause of the variability in retail sales.