For the following reports about statistical studies, identify the following items (if possible). If you can't tell, then say so-this often happens when we read about a survey.

The sample

A question posted on the gamefaqs.com website on August 1, 2011, asked visitors to the site, "Do you have an active social life outside the Internet?" 22% of the 55,581 respondents said "No" or "Not really, most of my personal contact is online."

A question posted on the gamefaqs.com website on August 1, 2011, asked visitors to the site, "Do you have an active social life outside the Internet?" 22% of the 55,581 respondents said "No" or "Not really, most of my personal contact is online." Can this survey be used to estimate the proportion of U.S. adults who would say they have an active social life outside the Internet? Why or why not?

For the following reports about statistical studies, identify the following items (if possible). If you can't tell, then say so-this often happens when we read about a survey.

The population

A question posted on the gamefaqs.com website on August 1, 2011, asked visitors to the site, "Do you have an active social life outside the Internet?" 22% of the 55,581 respondents said "No" or "Not really, most of my personal contact is online."

For the following reports about statistical studies, identify the following items (if possible). If you can't tell, then say so-this often happens when we read about a survey.

The sampling frame

A question posted on the gamefaqs.com website on August 1, 2011, asked visitors to the site, "Do you have an active social life outside the Internet?" 22% of the 55,581 respondents said "No" or "Not really, most of my personal contact is online."

A professional basketball player has embarked on a program to study his ability to shoot foul shots. On each day in which a game is not scheduled, he intends to shoot $100$ foul shots. He maintains records over a period of $40$ days of practice, with the results stored in Foulspc:

a. Construct a p chart for the proportion of successful foul shots. Do you think that the player's foul-shooting process is in statistical control? If not, why not?

Colleges use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Suppose the entering freshmen at a certain college have mean combined SAT scores of 1247, with a standard deviation of 128 . In the first semester, these students attained a mean GPA of 2.66 , with a standard deviation of 0.59 . A scatterplot showed the association to be reasonably linear, and the correlation between SAT score and GPA was 0.41 .

Write the equation of the regression line.

Colleges use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Regression analysis was computed on using SAT to predict GPA. Dependent variable is GPA R-squared = 22.1%

$$\begin{array} { l l } { \text { Variable } } & { \text { Coefficient } } \\ { \text { Intercept } } & { - 1.262 } \\ { \text { SAT } } & { 0.00214 } \end{array}$$

Interpret the slope of the regression line.

College s use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Regression analysis was computed on using SAT to predict GPA.

Dependent variable is GPA

R-squared = 22.1 %

Variable Coefficient Intercept

-1.262 SAT $\quad 0.00214$

Write the equation of the regression line

Each year thousands of high school students take either the SAT or the ACT, standardized tests used in the college admissions process. Combined SAT Math and Verbal scores go as high as 1600, while the maximum ACT composite score is 36. Since the two exams use very different scales, comparisons of performance are difficult. A convenient rule of thumb is SAT = 40 X ACT + 150; that is multiply an ACT score by 40 and add 150 points to estimate the equivalent SAT score. An admissions officer reported the following statistics about the ACT scores of 2355 students who applied to her college one year. Find the summaries of equivalent SAT scores. Lowest score = 19, Mean = 27, Standard deviation -3, Q3 = 30, Median = 28, IQR = 6

The SAT is the most widely used test in the undergraduate admissions process. Scores on the math portion of the SAT are believed to be normally distributed and range from 200 to 800 . A researcher from the admissions department at the University of New Hampshire is interested in estimating the mean math SAT scores of the incoming class with $90 \%$ confidence. How large a sample should she take to ensure that the margin of error is below 15 ?

Colleges use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Suppose the entering freshmen at a certain college have mean combined SAT scores of 1247, with a standard deviation of 128 . In the first semester, these students attained a mean GPA of 2.66 , with a standard deviation of 0.59 . A scatterplot showed the association to be reasonably linear, and the correlation between SAT score and GPA was 0.41

Interpret the slope of the regression line.

Colleges use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Regression analysis was computed on using SAT to predict GPA. Dependent variable is GPA R-squared = 22.1 %

$$\begin{array} { c l } { \text { Variable } } & { \text { Coefficient } } \\ { \text { Intercept } } & { - 1.262 } \\ { \text { SAT } } & { 0.00214 } \end{array}$$

Based upon these statistics, how effective do you think SAT scores would be in predicting academic success during the first semester of the freshman year at this college? Explain.

Colleges use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Suppose the entering freshmen at a certain college have mean combined SAT Scores of 1833, with a standard deviation of 123. In the first semester these students attained a mean GPA of 2.66, with a standard deviation of 0.56. A scatterplot showed the association to be reasonably linear, and the correlation between SAT score and GPA was 0.47.

Colleges use SAT scores in the admissions process because they believe these scores provide some insight into how a high school student will perform at the college level. Suppose the entering freshmen at a certain college have mean combined SAT scores of 1247, with a standard deviation of 128 . In the first semester, these students attained a mean GPA of 2.66 , with a standard deviation of 0.59 . A scatterplot showed the association to be reasonably linear, and the correlation between SAT score and GPA was 0.41

Based upon these statistics, how effective do you think SAT scores would be in predicting academic success during the first semester of the freshman year at this college? Explain.