Crawling

This study investigated whether babies take longer to learn to crawl in cold months when they are often bundled in clothes that restrict their movement, than in warmer months. The study sought an association between babies' first crawling age and the average temperature (Fahrenheit) during the month they first try to crawl (about 6 months after birth). Parents brought their babies into the University of Denver Infant Study Center between 1988-1991 for the study. The parents reported the birth month and age at which their child was first able to creep or crawl a distance of four feet in one minute. Data were collected on 208 boys and 206 girls (40 pairs of which were twins).The Crawling.csv dataset can be downloaded from the Data Repository. The file contains summary data including the number of infants born during each month, the mean and standard deviation of their crawling ages, and the average monthly temperature six months after the birth month. Using this data, you will determine if there is a linear relationship between temperature and crawling age. Which of the following variables will be considered to be the predictor?

Group of answer choices

1. Average temperature
2. Averagecrawlingage
3. Month of birth
4. Season of birth

Question 22

Calculate the correlation between temperature and average crawling age. Round your answer to three decimal places.

Question 23

Describe the correlation between temperature and average crawling age.

Group of answer choices

1. No correlation
2. Positive
3. Negative
4. Non-linear

Question 24

What is thep-value for the correlation between temperature and average crawling age? Round your answer to three decimal places. If thep-value is less than 0.001, round to 0.001.

Question 25

Calculate the lower bound of the 95%CIfor the correlation between temperature and average crawling age. Round your answer to three decimal places.

Question 26

Calculate the upper bound of the 95%CIfor the correlation between temperature and average crawling age. Round your answer to three decimal places.

Question 27

Which of the following statements best describes the correlation between temperature and average crawling age?

Group of answer choices

1. There was a statistically significant negative correlation betweentemperatureand average crawling age.
2. There was NO statistically significant correlation betweentemperatureand average crawling age.
3. Increased temperature causesignificantlyearlier average crawling ages.
4. There was no relationship between temperature and average crawling age.

Question 28

Perform a simple linear regression using temperature to predict average crawling age. What is ther-square value of the regression model? Round your answer to three decimal places.

Question 29

What is the value of the constant for the linear regression predicting average crawling age using temperature? Round your answer to three decimal places.

Question 30

Which of the following statements best defines theconstantfor the linear regression using temperature to predict average crawling age?

Group of answer choices

1. When temperature equals zero, the expected average crawling age will be 35.678.
2. For every one unit increase in temperature, the average crawling age increases by 35.678.
3. When temperature equals zero, the expected average crawling age will be 0.078.
4. For every one unit increase in temperature, theaveragecrawlingage decreases by -0.078.

Question 31

What is the value of the slope for the linear regression predicting average crawling age usingtemperature? Round your answer to three decimal places.

Question 32

Which of the following is the correct Alternate hypothesis for the Hypothesis test of the slope?

Group of answer choices

1. HA:? = 0
2. HA:? ?0
3. HA:? = 0
4. HA:? = 0

Question 33

What is the value of the test statistictfor the hypothesis test of the slope? Round your answer to three decimal places.

Question 34

What is thep-value for the hypothesis test of the slope? Round your answer to to three decimal places. Ifp-value is less than 0.001, round to 0.001.

Question 35

What is the lower bound of the 95%CIof the temperature slope for the linear regression predicting average crawling age? Round your answer to three decimal places.

Question 36

What is the upper bound of the 95%CIof the temperature slope for the linear regression predicting average crawling age? Round your answer to three decimal places.

Question 37

What is the correct decision for the hypothesis test of the slope?

Group of answer choices

1. Reject H0
2. Fail to Reject H0
3. Accept H0
4. Accept HA

Question 38

Which of the following statements best summarises the findings of the linear regression between temperature and average crawling age?

Group of answer choices

1. There was a statistically significant positive linear relationship between temperature and average crawling age.
2. There was NO statistically significant linear relationship between temperature and average crawling age.
3. Increased temperatures cause significantly earlier average crawling ages.
4. There was a statistically significant negative linear relationship between temperature and average crawling age.

birth_month avg_crawling_ageSD n temperature January 29.84 7.08 32 66 February 30.52 6.96 36 73 29.7 8.33 23 72 April 31.84 6.21 26 63 May 28.58 8.07 27 52 June 31.44 8.1 29 39 July 33.64 6.91 21 33 August 32.82 7.61 45 30 September 33.83 6.93 38 33 October 33.35 7.29 44 37 November 33.38 7.42 49 48 December 32.32 5.71 44 57 March