Statistics Questions & Answers

The Brigham Young University statistics department is performing randomized comparative experiments to compare teaching methods. Response variables include students' final-exam scores and a measure of their attitude toward statistics. One study compares two levels of technology for large lectures: standard (overhead projectors and chalk) and multimedia. The individuals in the study are the eight lectures in a basic statistics course. There are four instructors, each of whom teaches two lectures. Because the lecturers differ, their lectures form four blocks. Suppose the lectures and lecturers are as given in the table.Which outline describes an appropriate matched pairs design?

This graph, which combines the characteristics of a stacked bar chart and a line chart, shows changes in car/truck production. Which conclusion is best supported by the data in the chart?A) Consumers have always preferred trucks to cars.B) Manufacturers think sedans and wagons Sedan/Wagon are a growing market.C) Truck SUVs have become an important part of the market. Car SUVD) Truck manufacturers make more money Truck SUV than car manufacturers.

Small sample: Twenty seven concrete blocks were sampled and tested for crushing strength in order to estimate the proportion that were sufficiently strong or a certain application. Twenty five of the 27 blocks were sufficiently strong. Use the small-sample method to construct an \( 80 \% \) confidence interval for the proportion of blocks that are sufficiently strong. Round the answers to at least three decimal places. An \( 80 \% \) confidence interval for the proportion of blocks that are sufficiently strong is

Call me: A sociologist wants to construct a \( 99 \% \) confidence interval for the proportion of children aged \( 8-10 \) living in New York who own a smartphone. Part: \( 0 / 3 \) Part 1 of 3 (a) A survey by the National Consumers League estimated the nationwide proportion to be 0.40 . Using this estimate, what sample size is needed so tha the confidence interval will have a margin of error of 0.02 ? A sample of \( \square \) children aged \( 8-10 \) living in New York is needed to obtain a \( 99 \% \) confidence interval with a margin of error of 0.02 using the estimate 0.40 for \( p \).

Smart phone: Among 251 cell phone owners aged \( 18-24 \) surveyed, 109 said their phone was an Android phone. Part 1 of 3 (a) Find a point estimate for the proportion of cell phone owners aged 18 - 24 who have an Android phone. Round the answer to at least three decimal places. The point estimate for the proportion of cell phone owners aged \( 18-24 \) who have an Android phone is 0.434 . Part: \( \mathbf{1} / \mathbf{3} \quad \) Part 2 of 3 (b) Construct a \( 99.8 \% \) confidence interval for the proportion of cell phone owners aged \( 18-24 \) who have an Android phone. Round the answers to at least three decimal places. A \( 99.8 \% \) confidence interval for the proportion of cell phone owners aged \( 18-24 \) who have an Android phone is \( \square<p<\square \).

Smart phone: Among 251 cell phone owners aged \( 18-24 \) surveyed, 109 said their phone was an Android phone. Part: \( \mathbf{0 / 3} \) Part 1 of 3 (a) Find a point estimate for the proportion of cell phone owners aged 18 - 24 who have an Android phone. Round the answer to at least three decimal places. The point estimate for the proportion of cell phone owners aged \( 18-24 \) who have an Android phone is

Question 1: Find the range for each of the following \( \begin{array}{ll}\text { (a) } 5,9,1,5,7,4,3 & \text { (b) } 6,7,10,8,9,9\end{array} \)

Identifica la moda del siguiente conjunto de datos estadísticos. \( 3.2,7.7,4.1,0.9,4.1,3.2,0.9,11.4,2.5 \), \( 7.1,7.6,0.8 \) (O) 0.8 (O.2, \( 0.9,3.2,4.1 \) (o) \( 0.9,2.5,7.7 \)

3. Identifica la moda del siguiente conjunto de datos estadísticos. \( 8,14,2,7,11,10,10,7,3,7,1,7 \) () 10,14 ( 14 ( 7 (o) 10

Assume that a sample is used to estimate a population mean \( \mu \). Find the \( 99.9 \% \) confidence interval for a sample of size 75 with a mean of 44.5 and a standard deviation of 20.7 . Enter your answer as an open- interval (i.e., parentheses) accurate to one decimal place (because the sample statistics are reported accurate to one decimal place). \( 99.9 \% \) C.I. \( = \) Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places.