Retain Your Knowledge: Decision Making and Hunger Does hunger improve strategic decision making? That is, if you are hungry are you more likely to make a favorable decision when the outcome of your decision is uncertain (as in business decisions)? To test this theory, researchers randomly divided 30 normal weight individuals into two groups. All subjects were asked to refrain from eating or drinking (except water) from 11 P.M. on the day prior to their 9 A.M. meeting. At 9 A.M., the subjects were randomly assigned to one of two groups. The subjects in Group 1 were fed breakfast while the subjects in Group 2 were not fed. All subjects were administered a computerized version of an exam that assesses complex decision making under uncertain conditions. The assessment consisted of subjects choosing cards from four decks marked A, B, C, and D. Cards in decks A and B had a point value of 100 while cards in decks C and D had point values of 50. However, deck A had penalty cards that deducted points between 150 and 300; deck B had one penalty card of 1250; deck C had penalty cards between 25 and 75 points; deck D had a single penalty card of 250 points. So, decks A and B had stiffer penalties over the long haul than decks C and D and in the long haul, decks C and D resolted in more points than decks A and B. In total, the subjects would select 100 cards. However, the response variable was the number of cards selected from decks C and D out of the last 60 cards selected. The thinking here is that after 40 card selections, the subjects would be aware of the advantage of decks C and D. The researchers administered a Barret Impulsivity Scale to be sure the two groups did not differ in terms of impolsivity (e.g., “I do things without thinking”). There was no difference in impulsivity, age, or body mass index between the two groups. Before the exam, subjects were asked to report their level of hunger and it was found that Group 2 was significantly more hungry than Group 1. After analysis of the data, it was determined that the mean number of advantageous cards (decks C and D) selected by the subjects in Group 2 was 33.36 cards while the mean was 25.86 for the subjects in Group 1. The researchers concluded that hunger improves advantageous decision making.


f. What are the statistics in the study?

Verified step by step guidance

1. Identify the variables involved in the study. The main response variable is the number of advantageous cards (from decks C and D) selected out of the last 60 cards.
2. Determine the groups being compared. There are two groups: Group 1 (fed breakfast) and Group 2 (not fed, hungry).
3. Note the descriptive statistics provided: the mean number of advantageous cards selected by Group 2 is 33.36, and by Group 1 is 25.86.
4. Recognize that other statistics mentioned include measures to ensure groups were comparable, such as no significant differences in impulsivity, age, or body mass index.
5. Summarize the key statistics: group means of the response variable (advantageous cards selected), and the control statistics (impulsivity, age, BMI) that support the validity of the comparison.

Key Concepts

Randomized Controlled Experiment

A randomized controlled experiment involves randomly assigning participants to different groups to test the effect of a treatment or condition. This design helps control for confounding variables and biases, ensuring that differences in outcomes can be attributed to the treatment—in this case, feeding breakfast or not. Randomization increases the validity of causal conclusions.

Response Variable and Measurement

The response variable is the main outcome measured to assess the effect of the treatment. Here, it is the number of advantageous cards (from decks C and D) selected out of the last 60 cards, reflecting decision-making quality. Properly defining and measuring the response variable is crucial for analyzing and interpreting the study results.

Control of Confounding Variables

Controlling confounding variables means ensuring that other factors (like impulsivity, age, or BMI) do not differ between groups and influence the outcome. The study used the Barret Impulsivity Scale and demographic checks to confirm groups were similar, strengthening the claim that hunger alone affected decision making.