How much does a sleeping bag cost? Let's say you want a sleeping bag that should keep you warm in temperatures from 20°F to 45°F. A random sample of prices ($) for sleeping bags in this temperature range is given below. Assume that the population of x values has an approximately normal distribution.

105 75 85 80 65 50 30 23 100 110
105 95 105 60 110 120 95 90 60 70

(a) Use a calculator with mean and sample standard deviation keys to find the sample mean price x and sample standard deviation s. (Round your answers to two decimal places.)
x = $
s = $

(b) Using the given data as representative of the population of prices of all summer sleeping bags, find a 90% confidence interval for the mean price μ of all summer sleeping bags. (Round your answers to two decimal places.)
lower limit $
upper limit $

A purchaser of electrical components buys them in lots of size 10. It is his policy to inspect 3 components rendomly from a lot and to accept the lot only if all 3 are nondefective. If 30 percent of the lots have 4 defective components and 70 percent have only 1 what proportion of lots does the purchaser reject?

What percentage of i defective lots does the purchaser reject? Find it for i =1,4. Given that a lot is rejected, what is the conditional probability that it contained 4 defective components.

( I need the second part. I got the first question.)

Consider the hypothesis test below.

H ₀:  p ₁ -  p ₂  0  
H _a:  p ₁ -  p ₂ > 0

The following results are for independent samples taken from the two populations.

Use pooled estimator of p.

1. What is the value of the test statistic (to 2 decimals)?  
   
   
2. What is the  p-value (to 4 decimals)?  
   
   
3. With   = .05, what is your hypothesis testing conclusion?

# of mirrors                                              locus of control score

                                                      8                                                                     22

                                                      3                                                                     13

                                                      10                                                                  22

                                                      11                                                                  21

                                                      4                                                                     13

                                                      9                                                                     19

                                                      12                                                                  19

                                                      3                                                                     17

                                                      10                                                                  20

                                                      2                                                                     10

                                                      3                                                                     15

                                                      8                                                                     17

                                                      12                                                                  18

                                                      6                                                                     13

                                                      17                                                                  12

                                                      21                                                                  24

                                                      4                                                                     7

                                                      11                                                                  23

                                                      11                                                                  11

                                                      10                                                                  10

Give me the regression equation for the above data.  Also, determine whether there is a significant linear relationship between number of mirrors and locus of control score (be sure to include the null hypothesis tested and decision reached). Use SPSS and 20 participants.

In a club with 8 male and 10 female​ members, how many 4​-member committees can be chosen that have

​(a) at least 3 ​women?

​(b) no more than 2 ​men?

1. A scale measuring prejudice has been administered to a large sample of respondents. The distribution of scores is approximately normal, with a mean of 30 and a standard deviation of 5. What percent of the sample had scores…a. Below 20? b. Below 40? c. Between 30 and 40? d. Between 35 and 45? e. Above 25? f. Above 35?

Suppose a health psychologist conducted a weight loss program for middle aged adults and obtained the data presented in the table below. Use ANOVA to determine whether there is a difference in the three weight loss methods and whether the differences are statistically significant at the .05 level. What is your conclusion?

The Zone Weight Watchers Acupuncture
21 67 78
54 62 50
26 57 55
21 68 62
28 58 56
57 70 77
52 58 71
37 59 53
26 68 79
47 50 69

According to government data, 66% of employed women have never been married. Rounding to 4 decimal places, if 15 employed women are randomly selected: a. What is the probability that exactly 2 of them have never been married? b. That at most 2 of them have never been married? c. That at least 13 of them have been married?

4. The life expectancy of a person in 24 randomly selected countries for the year 2011 is in the table below.

   a.) What is the range of the life expectancy rates? b.) What is the median of the life expectancy rates?

   77.2	55.4	69.9	76.4	75.0	78.2
   73.0	70.8	82.6	68.9	81.0	54.2

   5) Cholesterol levels were collected from patients two days after they had a heart attack and are shown in the table below. (Show all work. Just the answer, without supporting work, will receive no credit.)

   270	236	210	142	280	272	160
   220	226	242	186	266	206	318
   294	282	234	224	276	282	360
   310	280	278	288	288	244	236

   1. a.) What is the sample mean?

   2. b.) What is the sample standard deviation? (Round your answer to two decimal

      places.

   3. 6) There are 4 black marbles and 6 red marbles in a box. Consider selecting one marble at a time from the box. What is the probability that the first marble is black and the second marble is also black. Express the probability in fraction format. (Show all work. Just the answer, without supporting work, will receive no credit.) a.) Assume the marble is selected with replacement. b.) Assume the marble is selected without replacement.

How much money do winners go home with from the television quiz show Jeopardy? To determine an answer, a random sample of winners was drawn and the amount of money each won was recorded and listed below. Estimate with 94% confidence the mean winning's for all the show's players. 26706 32076 33205 20633 32065 15777 18824 25347 25203 15531 26872 26022 25093 29789 33357 UCL = LCL =

Hypothesis Testing and Confidence Intervals

The Reliable Housewares store manager wants to learn more about the purchasing behavior of its

"credit" customers. In fact, he is speculating about four specific cases shown below (a) through (d) and

wants you to help him test their accuracy.

b. The true population proportion of credit customers who live in an urban area exceeds 55%

i. Using the dataset provided in Files perform the hypothesis test for each of the above speculations (a) through (d) in order to see if there is an statistical evidence to support the manager’s belief. In each case,

oUse the

Seven Elements of a Test of Hypothesis, in Section 7.1 of your textbook (on or about Page 361) or the Six Steps of Hypothesis Testing I have identified in the addendum.

oUse α=2%for all your analyses,

oExplain your conclusion in simple terms,

oIndicate which hypothesis is the“claim”,

o Compute the p-value,

o Interpret your results,

ii.Follow your work in (i) with computing a 98% confidence interval for each of the variables

described in (a) though (d). Interpret these intervals.

iii.

Write an executive summary for the Reliable Housewares store manager about your analysis,

distilling down the results in a way that would be understandable to someone who does not

know statistics. Clear explanations and interpretations are critical.

A certain medical test is known to detect 49% of the people who are afflicted with the disease Y. If 10 people with the disease are administered the test, what is the probability that the test will show that:

All 10 have the disease, rounded to four decimal places?

At least 8 have the disease, rounded to four decimal places?

At most 4 have the disease, rounded to four decimal places?

Please note that for all problems in this course, the standard cut-off (alpha) for a test of significance will be .05, and you always report the exact power unless SPSS output states p=.000 (you’d report p<.001). Also, remember that we divide the p value in half when reporting one-tailed tests with 1 – 2 groups.

9. Conduct the appropriate statistical analysis to determine if there is an effect of drug dose on CPT performance in ADHD patients. Paste SPSS output. (2 pts)

10. Create an appropriate graph for the data set. (2 pts)

11.   Write an APA-style Results section based on your analysis. All homework “Results sections” should follow the examples provided in the presentations and textbooks. They should include the statistical statement within a complete sentence that mentions the type of test conducted, whether the test was significant, and if relevant, effect size and/or post hoc analyses. Don’t forget to include a decision about the null hypothesis. (4 pts)

A. Complete the group frequency table.

Score            The Generals (f)             The Warriors (f)

80-89

90-99

100-109

110-119

B. Next, find the following for each team:

                                 Generals (f)                     Warriors (f)

c. What is the shape of distribution for the Generals? For the Warriors?

d. What is the range of scores that encompasses approx 68% of the scores surrounding the mean for EACH team?

e. Which distribution has a larger spread of scores? Why?

The number of cell phones per 100 residents in countries in Europe is given in table #1 for the year 2010. The number of cell phones per 100 residents in countries of the Americas is given in table #2 also for the year 2010 ("Population reference bureau," 2013).

Table #1: Number of Cell Phones per 100 Residents in Europe

Table #2: Number of Cell Phones per 100 Residents in the Americas

Is there enough evidence to show that the mean number of cell phones in countries of Europe is more than in countries of the Americas? Test at the 1% level.

(i) Let μ₁= mean number of cell phones per 100 residents in countries of Europe. Let μ₂ = mean number of cell phones per 100 residents in countries of the Americas. Which of the following statements correctly defines the null hypothesis H_O?

A.  μ₁ + μ₂= 0

B.  μ₁ – μ₂< 0 (μ₁ < μ₂)

C.  μ₁ − μ₂ > 0 (μ₁ > μ₂)

D.  μ₁ − μ₂ = 0 (μ₁ = μ₂)

Enter letter corresponding to correct answer

(ii)   Let μ₁= mean number of cell phones per 100 residents in countries of Europe. Let μ₂ = mean number of cell phones per 100 residents in countries of the Americas. Which of the following statements correctly defines the alternate hypothesis H_A?

A.  μ₁ − μ₂ > 0 (μ₁ > μ₂)

B.  μ₁ – μ₂< 0 (μ₁ < μ₂)

C.   μ₁ − μ₂ = 0 (μ₁ = μ₂)

D.  μ₁ + μ₂= 0

(iii) Enter the level of significance α used for this test:

(iv)  For sample from population with mean = μ1 :          Determine sample mean x¯1 and sample standard deviation s1variant

(v)  For sample from population with mean = μ2 :       Determine sample mean x¯2 and sample standard deviation s2

(vi) Determine degrees of freedom df :

(vii) Determine test statistic:

Enter value in decimal form rounded to nearest thousandth.  

(viii) Determine and enter p-value corresponding to test statistic.

Enter value in decimal form rounded to nearest ten-thousandth.  

(ix) Comparing p-value and α value, which is the correct decision to make for this hypothesis test?

A. Accept H_o

B. Fail to reject H_o

C. Reject H_o

D. Accept H_A

(x) Select the statement that most correctly interprets the result of this test:

A. The result is not statistically significant at .01 level of significance. Sufficient evidence exists to support the claim that the mean number of cell phones in countries of Europe is more than in countries of the Americas.

B. The result is not statistically significant at .01 level of significance. There is not enough evidence to support the claim that the mean number of cell phones in countries of Europe is more than in countries of the Americas.

C. The result is statistically significant at .01 level of significance. Sufficient evidence exists to support the claim that the mean number of cell phones in countries of Europe is more than in countries of the Americas.

D. The result is statistically significant at .01 level of significance. There is not enough evidence to support the claim that the mean number of cell phones in countries of Europe is more than in countries of the Americas.