The basic pratice of Statistics question 3 142She sounds tal

The basic pratice of Statistics question 3

1.42She sounds tall! Presented with recordings of a pair of people of the same sex speaking the same phrase, can a listener determine which speaker is taller simply from the sound of their voice? Twenty four young adults at Washington University listened to 100 pairs of speakers, and within each pair were asked to indicate which of the two speakers was the taller. Here are the number correct (out of 100 for each of the 24 30 participants 65 61 67 59 58 62 56 67 61 67 63 53 68 49 66 58 69 70 65 56 68 56 58 70 Researchers believe that the key to correct discrimination is contained in a particular type of sound produced in the lower airways or the lungs, known as subglottal resonances, whose frequency is lower for taller people. Despite the masking of these resonances by other voice sounds, researchers wondered whether the information they contained could still be heard by listeners and used to identify the taller person. (a)Make two stemplots, with and without splitting the stems. Which plot do you prefer and why? (b)Describe the shape, center, and variability of the distribution. Are there any outliers? (c)If the experimental subjects are just guessing which speaker is taller, they should correctly identify the taller person about 50% of the time. Does this data support the researchers, conjecture that there is information in a person\'s voice to help identify the taller person? Why or why not?

Solution

answer of part(a)

stempolts wthout splitting stems

The decimal point is at the |

48 | 0
50 |
52 | 0
54 |
56 | 000
58 | 0000
60 | 00
62 | 00
64 | 00
66 | 0000
68 | 000
70 | 00

stemplots with splitging stems

The decimal point is 1 digit(s) to the right of the |

4 | 9
5 | 3
5 | 6668889
6 | 1123
6 | 556777889
7 | 00

we preference will be give to splitting of stem, because it gives more idear about varibility.

answer of part(b)

mean=62.17

median=62.5

positively skewed and mesokurtic

there is one outliers i.e. 49

answer of part(c)

data doesnot support because at alpha=5% level of there should be only 5% wrongly identification is permitted.Here it is not show.