To assess the impact of undercoverage, nonresponse, and other sampling errors, one can compare sample data with known population figures. In Canada, approximately 24% of the population aged over 15 are first-generation, having been born outside of the country. Consequently, in random samples of 1000 individuals aged over 15, the number of first-generation Canadians (X) should conform to a binomial distribution with n = 1000 and p = 0.24. (a) The mean (μ) and standard deviation (σ) of X are: Mean (μ) = np = 1000 × 0.24 = 240 Standard deviation (σ) = √(np(1 - p)) = √(1000 × 0.24 × 0.76) ≈ 13.8564. (b) To calculate the probability of the sample containing between 210 and 270 first-generation Canadians using normal approximation: First, verify the appropriateness of the normal approximation by ensuring: 1. np ≥ 5 2. n(1 - p) ≥ 5 Since np = 240 and n(1 - p) = 760, both criteria are met. Next, determine the z-scores for 210 and 270: Z for 210 = (210 - μ) / σ = (210 - 240) / 13.8564 ≈ -2.166 Z for 270 = (270 - μ) / σ = (270 - 240) / 13.8564 ≈ 2.166 Then, using a standard normal distribution table or calculator, find the probabilities for these z-scores and calculate the probability that X is between 210 and 270. Probability(X is between 210 and 270) ≈ P(Z < 2.166) - P(Z < -2.166).

Mathematics · College · Thu Feb 04 2021

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To calculate the mean (μ) and the standard deviation (σ) for the binomial distribution described, you correctly used the formulas:

1000 * 0.24 = 240 σ = √(1000 * 0.24 * (1 - 0.24)) = √(1000 * 0.24 * 0.76) ≈ 13.8564

 For the normal approximation, you initiated the process correctly by verifying that the sample distribution satisfies the criteria for a normal approximation:

1. np = 240 ≥ 5 2. n(1 - p) = 760 ≥ 5

Both conditions are met, thus a normal approximation can be used.

Next, you calculated the z-scores correctly:

Z for 210 = (210 - μ) / σ = (210 - 240) / 13.8564 ≈ -2.166 Z for 270 = (270 - μ) / σ = (270 - 240) / 13.8564 ≈ 2.166

Then, you will need to find the area under the normal curve corresponding to these z-scores. Unfortunately, a slight correction is needed here. The probability that X is between 210 and 270 will be found by:

Probability(X is between 210 and 270) ≈ P(Z ≤ 2.166) - P(Z ≤ -2.166)