3 it is generally believed that nearsightedness affects about 12% of children. A school district gives vision tests to 133 incoming kindergarten childrer a. Describe the sampling distribution model for the sample proportion by finding its mean and standard deviation and showing how it justifies using the Normal model. b. Sketch and clearly label the model. c. What is the probability that in this group over 15% of the children will be found to be nearsighted?

Examine the normal quantile plot and determine whether it depicts sample data from a population with a normal distribution. C Does the normal quantile plot depict sample data from a population with a normal distribution? O A. No. The points exhibit some systematic pattern that is not a straight-line pattern. O B. Yes. The pattern of the points is reasonably close to a straight line. O C. Yes. The points are evenly distributed above and below the mean, 0. O D. No. The points do not lie close to a straight line. 3.00- 2.00- 1.00- 0.00- -1.00- -2.00- -3.00+ X 60 80 100 120 140

Jason collects information about annual family income from each student at his college. He computes both the mean and median family income across all students and is surprised to find that the mean income is much higher than the median income. What is the most likely reason for the difference in the mean and the median? Select one: a. The sample size is too small. b. The median tends to produce lower estimates of central tendency. c. The median is not an appropriate estimate for annual family income's level of measurement. Incorrect d. The mean is more affected by a small number of extreme values.

1. Consider a sample with data values of 2.20; 1.98; 1.95; 2.27; 2.25; 2,24; 2.31 Compute the mean.

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3. Calculate the mean, median, mode, variance, and standard deviation for each of the following two groups of scores, which represent student performance on a health science test, with the highest possible score being 50. Group A 35 49 33 44 45 21 28 411 Group B 20 25 50 44 16 29 37 21 40 39 23 26 a. Which group has the greatest variability in scores? b. Which group has the highest mean score? c. How would you describe each group when comparing it to the other?

A primary measure of dispersion for sample data is the sample standard deviation, s.  Choose the best option to explain what the meaning of the sample standard deviation is, in general.   A. The distance between one observation and the mean. B. The average distance of an observation from the middle of the distribution. C. The average distance between observations in the sample. D. The distance between the third and first quartiles.

According to one study, brain weights of men are normally distributed with a mean of 1.10 kg and a standard deviation of 0.12 kg. Use the data to answer parts (a) through (e). Click here to view page 1 of the table of areas under the standard normal curve. Click here to view page 2 of the table of areas under the standard normal curve. a. Determine the sampling distribution of the sample mean for samples of size 3. Interpret your answer in terms of the distribution of all possible sample mean brain weights for samples of three men. The mean of the sample mean is µ, kg. (Type an integer or a decimal. Do not round.) The standard deviation of the sample mean is o, = kg. (Round to four decimal places as needed.) Interpret these answers in context. For the brain weights have a normal distribution with a mean of kg and a standard deviation of kg. (Type integers or decimals rounded to four decimal places as needed.) b. Repeat part (a) for samples of size 12. The mean of the sample mean is µ;…

Suppose you are asked to toss a coin 16 times and calculate the proportion of the tosses that were heads. a.    What shape would you expect this histogram to be and why? b.    Where you do expect the histogram to be centered? c.    How much variability would you expect among these proportions? d.    Explain why a Normal model should not be used here.

2. Given the following observations from a sample, calculate the mean, the median, and the mode. 4 0 -6 1 -3 -4