Exam 12: Experiments With More Than One Independent Variable

Dr. Elder was interested in the way people recognize objects as members of categories. For example, what makes us recognize a dog as being a dog and not a cat? More specifically, he was curious as to whether people think about categories in a more complex way if they contemplate an "opposite" category first. For example, does a person think differently about the category of "southern" if they first think about the category of "northern"? He is also curious as to whether people categorize differently if they are exposed to category members compared with generating category members. Dr. Elder has four groups of participants (with 30 people in each group). In Group A, participants were told to cut out pictures of dogs and cats from magazines. In Group B, participants were told to cut out pictures of just dogs from magazines. In Group C, participants were told to draw pictures of cats and dogs. In Group D, participants were told to draw pictures of just dogs. After doing this for 30 minutes, participants in all groups were asked to list the attributes that define the "dog" category. Having a higher number of attributes listed was considered to be an indication of thinking about the category in a more complex way. The results of his study are below. By examining the marginal means, it appears that in this study:

Dr. Elder was interested in the way people recognize objects as members of categories. For example, what makes us recognize a dog as being a dog and not a cat? More specifically, he was curious as to whether people think about categories in a more complex way if they contemplate an "opposite" category first. For example, does a person think more differently about the category of "southern" if they are also thinking about the category of "northern"? He is also curious as to whether people categorize differently if they are exposed to category members compared with generating category members. Dr. Elder has four groups of participants (with 30 people in each group). In Group A, participants were told to cut out pictures of dogs and cats from magazines. In Group B, participants were told to cut out pictures of just dogs from magazines. In Group C, participants were told to draw pictures of cats and dogs. In Group D, participants were told to draw pictures of just dogs. After doing this for 30 minutes, participants in all groups were asked to list the attributes that define the "dog" category. Having a higher number of attributes listed was considered to be an indication of thinking about the category in a more complex way. Dr) Elder also is curious as to whether categorization happens similarly for children as it does for adults. As such, he recruits a group of 10-year-olds and a group of 20-year-olds to participate in the study. The results are below. Dr) Elder will need to examine how many two-way interactions?

If a person describes the results of a study to you by saying that there is a zero difference in one condition but a large difference in another condition, the person is most likely describing which of the following?

To study the effects of physical discomfort on attention, Dr. Lopez conducted the following study: A group of participants were required to keep one hand submerged in cold water (52 degrees). Half of the participants kept their hand in the water for 2 minutes, and half of the participants kept their hand in the water for 4 minutes. In addition, half of the participants were given a placebo pill and told it would reduce the pain of the water (pain relief assumed). The other half were given a placebo pill and told that it would have no effect (no pain relief assumed). While their hands were in the water, participants were asked to watch a video where a ball is quickly passed between and underneath three cups. At the end of the video, participants were asked to indicate under which cup the ball could be found. Whether or not the participant picked the correct cup was recorded (as a measure of whether they were paying attention). The results are below. Imagine that Dr. Lopez decides to add an additional variable to his study. He is curious as to whether the results of the study vary based on sex (male and female). The graphs of the results are below. Discuss whether Dr. Lopez should conclude that a three-way interaction exists in his study.

A "difference in the difference between the differences" would indicate which of the following?

Dr. Elder was interested in the way people recognize objects as members of categories. For example, what makes us recognize a dog as being a dog and not a cat? More specifically, he was curious as to whether people think about categories in a more complex way if they contemplate an "opposite" category first. For example, does a person think more differently about the category of "southern" if they are also thinking about the category of "northern"? He is also curious as to whether people categorize differently if they are exposed to category members compared with generating category members. Dr. Elder has four groups of participants (with 30 people in each group). In Group A, participants were told to cut out pictures of dogs and cats from magazines. In Group B, participants were told to cut out pictures of just dogs from magazines. In Group C, participants were told to draw pictures of cats and dogs. In Group D, participants were told to draw pictures of just dogs. After doing this for 30 minutes, participants in all groups were asked to list the attributes that define the "dog" category. Having a higher number of attributes listed was considered to be an indication of thinking about the category in a more complex way. Dr) Elder also is curious as to whether categorization happens similarly for children as it does for adults. As such, he recruits a group of 10-year-olds and a group of 20-year-olds to participate in the study. The results are below. The addition of the new variable to Dr. Elder's study could be thought of as which of the following?

The number of main effects that need to be examined is the number of independent variables.

Dr. Elder was interested in the way people recognize objects as members of categories. For example, what makes us recognize a dog as being a dog and not a cat? More specifically, he was curious as to whether people think about categories in a more complex way if they contemplate an "opposite" category first. For example, does a person think more differently about the category of "southern" if they are also thinking about the category of "northern"? He is also curious as to whether people categorize differently if they are exposed to category members compared with generating category members. Dr. Elder has four groups of participants (with 30 people in each group). In Group A, participants were told to cut out pictures of dogs and cats from magazines. In Group B, participants were told to cut out pictures of just dogs from magazines. In Group C, participants were told to draw pictures of cats and dogs. In Group D, participants were told to draw pictures of just dogs. After doing this for 30 minutes, participants in all groups were asked to list the attributes that define the "dog" category. Having a higher number of attributes listed was considered to be an indication of thinking about the category in a more complex way. Dr) Elder also is curious as to whether categorization happens similarly for children as it does for adults. As such, he recruits a group of 10-year-olds and a group of 20-year-olds to participate in the study. The results are below. Which of the following reasons might Dr. Elder have for changing his study in this way?

Imagine that you read the following passage in a journal article. Provide three pieces of information that this passage tells the reader about the study conducted. "A 3 × 4 within-subjects design was specified that varied color of paper (blue, pink, white) and font size (10 point, 12 point, 14 point, 16 point). The time it took participants to read the printed word was measured."

To study the effects of physical discomfort on attention, Dr. Lopez conducted the following study: A group of participants were required to keep one hand submerged in cold water (52 degrees). Half of the participants kept their hand in the water for 2 minutes, and half of the participants kept their hand in the water for 4 minutes. In addition, half of the participants were given a placebo pill and told it would reduce the pain of the water (pain relief assumed). The other half were given a placebo pill and told that it would have no effect (no pain relief assumed). While their hands were in the water, participants were asked to watch a video where a ball is quickly passed between and underneath three cups. At the end of the video, participants were asked to indicate under which cup the ball could be found. Whether or not the participant picked the correct cup was recorded (as a measure of whether they were paying attention). The results are below. Using the marginal means, state whether it appears that the main effects in Dr. Lopez's study are important. (You do not need to say whether the main effects are statistically significant but simply whether a difference appears to exist.)

Dr. Rhodes notices an interaction in his factorial study. In describing this, which statement might he use to explain the link between Independent Variable A and Independent Variable B in predicting the dependent variable?

Dr. Elder was interested in the way people recognize objects as members of categories. For example, what makes us recognize a dog as being a dog and not a cat? More specifically, he was curious as to whether people think about categories in a more complex way if they contemplate an "opposite" category first. For example, does a person think differently about the category of "southern" if they first think about the category of "northern"? He is also curious as to whether people categorize differently if they are exposed to category members compared with generating category members. Dr. Elder has four groups of participants (with 30 people in each group). In Group A, participants were told to cut out pictures of dogs and cats from magazines. In Group B, participants were told to cut out pictures of just dogs from magazines. In Group C, participants were told to draw pictures of cats and dogs. In Group D, participants were told to draw pictures of just dogs. After doing this for 30 minutes, participants in all groups were asked to list the attributes that define the "dog" category. Having a higher number of attributes listed was considered to be an indication of thinking about the category in a more complex way. The results of his study are below. To determine if there is a main effect for type of activity, Dr. Elder must examine how many marginal means?

Dr. Gavin is conducting a 2 × 4 independent-groups factorial design. How many independent variables are in his study?

You read an article that states, "How well you remember different types of information depends on the context in which you learned them." Based on this information, what else is true about this study?

Dr. Elder was interested in the way people recognize objects as members of categories. For example, what makes us recognize a dog as being a dog and not a cat? More specifically, he was curious as to whether people think about categories in a more complex way if they contemplate an "opposite" category first. For example, does a person think differently about the category of "southern" if they first think about the category of "northern"? He is also curious as to whether people categorize differently if they are exposed to category members compared with generating category members. Dr. Elder has four groups of participants (with 30 people in each group). In Group A, participants were told to cut out pictures of dogs and cats from magazines. In Group B, participants were told to cut out pictures of just dogs from magazines. In Group C, participants were told to draw pictures of cats and dogs. In Group D, participants were told to draw pictures of just dogs. After doing this for 30 minutes, participants in all groups were asked to list the attributes that define the "dog" category. Having a higher number of attributes listed was considered to be an indication of thinking about the category in a more complex way. The results of his study are below. Which of the following could be said of the focus of activity variable in Dr. Elder's study?

Dr. Gavin decides that instead of conducting a 2 × 4 independent-groups factorial design, he is going to conduct a 2 × 3 × 4 mixed factorial design. Which of the following things will NOT have to change?

Dr. Green is interested in conducting a 2 × 2 × 3 mixed factorial design, with 20 participants in each cell. Which of the following would NOT be a possible number of participants for this study?

What is the difference between a main effect and an overall effect?

To study the effects of physical discomfort on attention, Dr. Lopez conducted the following study: A group of participants were required to keep one hand submerged in cold water (52 degrees). Half of the participants kept their hand in the water for 2 minutes, and half of the participants kept their hand in the water for 4 minutes. In addition, half of the participants were given a placebo pill and told it would reduce the pain of the water (pain relief assumed). The other half were given a placebo pill and told that it would have no effect (no pain relief assumed). While their hands were in the water, participants were asked to watch a video where a ball is quickly passed between and underneath three cups. At the end of the video, participants were asked to indicate under which cup the ball could be found. Whether or not the participant picked the correct cup was recorded (as a measure of whether they were paying attention). The results are below. Using the data table alone, discuss whether Dr. Lopez should conclude that an interaction exists in his study.

According to the textbook, why is it important to study interactions?