STAT 200-A study indicated that 57 out of 104 pregnant

STAT 200-A study indicated that 57 out of 104 pregnant

Subject: Mathematics    / Statistics
Question

1. A study indicated that 57 out of 104 pregnant women correctly guessed the sex of their babies. Use these sample data to test the claim that the success rated of such guesses is no different from the 50% success rate expected with random chance guesses. Use a 0.05 significance level.

2. Assume we are conducting a hypothesis test of the claim that a method of gender selection increases the likelihood of a baby girl, so that the probability of a baby girl is p > 0.5. Here are the null and alternative hypotheses:

H0: p = 0.5

H1: p > 0.5

Give statements identifying the following.

a. Type I error b. Type II error

3.

Year

1960

1973

1986

1995

2002

2003

Cost of slice of Pizza

0.15

0.35

1.00

1.25

1.75

2.00

Subway fare

0.15

0.35

1.00

1.35

1.50

2.00

CPI

30.2

48.3

112.3

162.2

191.9

197.8

Using the data in the table, construct a scatter plot of the pizza cost (x) versus the subway fare (y). Determine the regression line including the correlation coefficient (r) and the explained variation (r2). Show your scatter plot and line on a graph.

Explain what the y-intercept, slope, r and r2 mean and whether the relationship makes any sense.