Concept explainers
Naughty or Nice? An experiment was conducted in which 16 ten-month-old babies were asked to watch a climber character attempt to ascend a hill. On two occasions, the baby witnesses the character fail to make the climb. On the third attempt, the baby witnesses either a helper toy push the character up the hill, or a hinderer toy preventing the character from making the ascent. The helper and hinderer toys were shown to each baby in a random fashion for a fixed amount of time. In Problem 39 from Section 10.2, we learned that, after watching both the helper and hinderer toy in action, 14 of 16 ten-month-old babies preferred to play with the helper toy when given a choice as to which toy to play with. A second part of this experiment showed the climber approach the helper toy, which is not a surprising action, and then alternatively the climber approached the hinderer toy, which is a surprising action. The amount of time the ten-month-old watched the
Source: J. Kiley Hamlin et al., “Social Evaluation by Preverbal Infants,” Nature, Nov. 2007.
- a. State the null and alternative hypothesis to determine if babies tend to look at the hinderer toy longer than the helper toy.
- b. Assuming the differences are
normally distributed with no outliers, test if the difference in the amount of time the baby will watch the hinderer toy versus the helper toy is greater than 0 at the 0.05 level of significance. - c. What do you think the results of this experiment imply about 10-month-olds’ ability to assess surprising behavior?
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Fundamentals of Statistics (5th Edition)
- Student researchers at Hope College conducted an experiment to determine whether students memorize material better if they are taking notes on paper using handwriting as opposed to taking notes on a computer. They randomly assigned 20 students to the paper-based note-taking group and 20 students to the computer-based note-taking group. They showed all their subjects a 12-minute video about the sun and they were allowed to take notes in the method they were assigned. After the video was over, the notes were collected, and the students were given a 10-question quiz over information about the sun given in the video. Do students tend to memorize better using hand-written notes? (The results data are in the file NoteTaking picture)arrow_forwardStudent researchers at Hope College conducted an experiment to determine whether students memorize material better if they are taking notes on paper using handwriting as opposed to taking notes on a computer. They randomly assigned 20 students to the paper-based note-taking group and 20 students to the computer-based note-taking group. They showed all their subjects a 12-minute video about the sun and they were allowed to take notes in the method they were assigned. After the video was over, the notes were collected, and the students were given a 10-question quiz over information about the sun given in the video. Do students tend to memorize better using hand-written notes? (The results data are in the file NoteTaking.)arrow_forwardOne game at a carnival is called “Duck Pond.” This game consists of a large number of ducks that arefloating through an oval-shaped trough. A sign claims that 20% of the ducks have a blue dot on thebottom of them, 20% have a red dot, 20% have a green dot, 20% have a yellow dot, and 20% have anorange dot. Players pay to select one duck, show the color to the game attendant, replace the duck, spinaround once, and then select a second duck. If the dot on the bottom of the second duck matches the dotthat was on the bottom of the first duck, the player wins. Otherwise, the player loses. a) Are the events “color of the first duck” and “color of the second duck” independent? Explain. b) You want to perform a simulation to estimate the probability of winning this game, assuming theduck colors are distributed as claimed. Describe how you could use a table of random digits tocarry out this simulation without needing to skip any digits. c) Perform 10 trials of the simulation described in part (b)…arrow_forward
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