A manufacturer of game controllers is concerned that its controller may be difficult for left-handed users. They set out to find lefties to test. About 11%
of the population is left-handed. If they select a sample of 6 customers at random in their stores, what is the probability of each of the outcomes described in parts a through f below?
a. The first lefty is the sixth person chosen
b. There are some lefties among the 6 people
c. The first lefty is the second or third person
d. There are exactly 3 lefties in the group
e. There are at least 3 lefties in the group
f. There are no more than 3 lefties in the group
(round to four decimal places)
In: Math
A marketing researcher wants to estimate the mean amount spent per year ($) on a web site by membership member shoppers. Suppose a random sample of 100 membership member shoppers who recently made a purchase on the web site yielded a mean amount spent of $57 and a standard deviation of $ 54 Complete parts (a) and (b) below.
a. Is there evidence that the population mean amount spent per year on the web site by membership member shoppers is different from %51 (Using a .01 level of significance)
Identify the critical value(s).
Determine the test statistic.
State the conclusion.
Determine the p-value and interpret its meaning
In: Math
A certain system can experience three different types of defects. Let Ai (i = 1,2,3) denote the event that the system has a defect of type i. Suppose that the following probabilities are true. P(A1) = 0.10 P(A2) = 0.08 P(A3) = 0.06 P(A1 ∪ A2) = 0.12 P(A1 ∪ A3) = 0.13 P(A2 ∪ A3) = 0.12 P(A1 ∩ A2 ∩ A3) = 0.01 (c) Given that the system has at least one type of defect, what is the probability that it has exactly one type of defect? (Round your answer to four decimal places.) (d) Given that the system has both of the first two types of defects, what is the probability that it does not have the third type of defect? (Round your answer to four decimal places.)
In: Math
A friend who lives in Los Angeles makes frequent consulting trips to Washington, D.C.; 40% of the time she travels on airline #1, 30% of the time on airline #2, and the remaining 30% of the time on airline #3. For airline #1, flights are late into D.C. 35% of the time and late into L.A. 25% of the time. For airline #2, these percentages are 35% and 20%, whereas for airline #3 the percentages are 15% and 10%. If we learn that on a particular trip she arrived late at exactly one of the two destinations, what are the posterior probabilities of having flown on airlines #1, #2, and #3? Assume that the chance of a late arrival in L.A. is unaffected by what happens on the flight to D.C. [Hint: From the tip of each first-generation branch on a tree diagram, draw three second-generation branches labeled, respectively, 0 late, 1 late, and 2 late.] (Round your answers to four decimal places.) airline #1 airline #2 airline #3
In: Math
Consider the following information about travelers on vacation: 40% check work email, 30% use a cell phone to stay connected to work, 25% bring a laptop with them, 16% both check work email and use a cell phone to stay connected, and 44% neither check work email nor use a cell phone to stay connected nor bring a laptop. In addition, 88 out of every 100 who bring a laptop also check work email, and 70 out of every 100 who use a cell phone to stay connected also bring a laptop. (a) What is the probability that a randomly selected traveler who checks work email also uses a cell phone to stay connected? Incorrect: Your answer is incorrect. (b) What is the probability that someone who brings a laptop on vacation also uses a cell phone to stay connected? (c) If the randomly selected traveler checked work email and brought a laptop, what is the probability that he/she uses a cell phone to stay connected? (Round your answer to four decimal places.)
In: Math
This problem is going to use the data set in R called "ChickWeight" that has 4 variables, as described below.
ChickWeight:
A data frame with 578 observations on 4 variables.
1) weight: a numeric vector giving the body weight of the chick
(gm).
2) Time: a numeric vector giving the number of days since birth
when the measurement was made.
3) Chick: an ordered factor with levels 18 < ... < 48 giving
a unique identifier for the chick. The ordering of the levels
groups chicks on the same diet together and orders them according
to their final weight (lightest to heaviest) within diet.
4) Diet: a factor with levels 1, ..., 4 indicating which
experimental diet the chick received.
Using a significance level of 0.05, is there evidence to support that the weight can be determined by the Time, Diet, and the interaction between the two? (Appears as Time:Diet in RStudio)
Fill in the R code below.
dat.aov = aov( ~ factor( ) * , data= )
summary( )
Fill in the ANOVA table below.
Type the values into the table EXACTLY as they appear in your
output in RStudio.
df | SS | MS | F | Pr(>F) | |
factor(Time) | 2e-16 | ||||
Diet | 2e-16 | ||||
factor(Time):Diet | 0.00017 | ||||
Residuals |
Is there evidence to support a significant interaction between
Time and Diet?
1. ?0:H0: No AB interaction vs ??:Ha: Factors A and B
interact
2. ?=0.05α=0.05
3. F =
4. ??Fα =
5. Conclusion:
Reject H0
Fail to reject H0
Interpretation:
There is sufficient evidence to support that the interaction
between Time and Diet is significant.
There is not sufficient evidence to support that the interaction
between Time and Diet is significant.
In: Math
A defective car has a probability of 2/3 upon turning on the ignition in each attempt. Assume attempts
are independent.
• (a) What is the probability that exactly 3 attempts are needed until the car starts?
• (b) What is the probability that 3 or 4 attempts are needed?
• (c) What is the probability of success in 4 or more trials?
In: Math
This problem is going to use the data set in R called "ChickWeight" that has 4 variables, as described below.
ChickWeight:
A data frame with 578 observations on 4 variables.
1) weight: a numeric vector giving the body weight of the chick
(gm).
2) Time: a numeric vector giving the number of days since birth
when the measurement was made.
3) Chick: an ordered factor with levels 18 < ... < 48 giving
a unique identifier for the chick. The ordering of the levels
groups chicks on the same diet together and orders them according
to their final weight (lightest to heaviest) within diet.
4) Diet: a factor with levels 1, ..., 4 indicating which
experimental diet the chick received.
Using a significance level of 0.05, is there evidence to support that the weight can be determined by the Time (treatment) and Diet (block)?
Fill in the R code below.
dat.aov=aov( ~ factor( ) + ,data= )
summary( )
Fill in the ANOVA table below.
Type the values into the table EXACTLY as they appear in your
output in R.
df | SS | MS | F | Pr(>F) | |
factor(Time) | 2e-16 | ||||
Diet | 2e-16 | ||||
Residuals |
Is there evidence to support that the treatment variable Time is
significant?
1. ?0:?1=?2=...=?12H0:μ1=μ2=...=μ12 vs ??:????Ha:ALOI
2. ?=0.01α=0.01
3. F =
4. ??Fα =
5. Conclusion:
Reject H0
Fail to reject H0
Interpretation:
There is sufficient evidence to support that the variable Time is
significant.
There is not sufficient evidence to support that the variable Time
is significant.
Is there evidence to support that the block variable Diet is
significant?
1. ?0:H0: No block effect vs ??:Ha: There is a block effect
2. ?=0.01α=0.01
3. F =
4. ??Fα =
5. Conclusion:
Reject H0
Fail to reject H0
Interpretation:
There is sufficient evidence to support that the variable Diet is
significant.
There is not sufficient evidence to support that the variable Diet
is significant.
In: Math
There are 6 purple balls, 5 blue balls, and 3 green balls in a box. 5 balls were randomly chosen (without replacing them). Find the probability that
(a) Exactly 3 blue balls were chosen.
(b) 2 purple balls, 1 blue ball, and 2 green balls were chosen.
In: Math
1. STATISTICAL RESULTS: Report and statistically interpret the results with an appropriate tabular format and text. See the Output B. [6 pt]
2. DISCUSSION: Discuss what the results imply. [2 pt]
Output A. Descriptive statistics
Statistics |
|||
Exam Performance (%) |
Exam Anxiety |
||
N |
Valid |
103 |
103 |
Missing |
0 |
0 |
|
Mean |
56.57 |
74.3437 |
|
Median |
60.00 |
79.0440 |
|
Std. Deviation |
25.941 |
17.18186 |
|
Minimum |
2 |
1.00 |
|
Maximum |
100 |
100.00 |
Output B. Simple Linear Regression Results
Correlations |
|||
Exam Performance (%) |
Exam Anxiety |
||
Pearson Correlation |
Exam Performance (%) |
1.000 |
-.441 |
Exam Anxiety |
-.441 |
1.000 |
|
Sig. (1-tailed) |
Exam Performance (%) |
. |
.000 |
Exam Anxiety |
.000 |
. |
|
N |
Exam Performance (%) |
103 |
103 |
Exam Anxiety |
103 |
103 |
Model Summary |
||||
Model |
R |
R Square |
Adjusted R Square |
Std. Error of the Estimate |
1 |
.441a |
.194 |
.186 |
23.397 |
a. Predictors: (Constant), Exam Anxiety |
Coefficientsa |
||||||||
Model |
Unstandardized Coefficients |
Standardized Coefficients |
t |
Sig. |
95.0% Confidence Interval for B |
|||
B |
Std. Error |
Beta |
Lower Bound |
Upper Bound |
||||
1 |
(Constant) |
106.071 |
10.285 |
10.313 |
.000 |
85.667 |
126.474 |
|
Exam Anxiety |
-.666 |
.135 |
-.441 |
-4.938 |
.000 |
-.933 |
-.398 |
|
a. Dependent Variable: Exam Performance (%) |
In: Math
In: Math
Figure shows a contact lens table tht contains information about contact lens prescriptions (hard, soft and no contact lens) From the table derive quantitative association rules by mapping tables to Boolean association rules.
ID |
Age |
Spectacle |
Astigmatic |
Tear Production |
Contact lens |
1 |
21 |
Myope |
No |
Reduced |
None |
2 |
24 |
Myope |
No |
Normal |
Soft |
3 |
20 |
Myope |
Yes |
Reduced |
None |
4 |
26 |
Myope |
Yes |
Normal |
Hard |
5 |
27 |
Hypermyope |
No |
Reduced |
None |
6 |
22 |
Hypermyope |
No |
Normal |
Soft |
7 |
28 |
Hypermyope |
Yes |
Reduced |
None |
8 |
27 |
Hypermyope |
Yes |
Normal |
Hard |
9 |
38 |
Myope |
No |
Reduced |
None |
10 |
32 |
Myope |
No |
Normal |
Soft |
11 |
36 |
Myope |
Yes |
Reduced |
None |
12 |
37 |
Myope |
Yes |
Normal |
Hard |
13 |
33 |
Hypermyope |
No |
Reduced |
None |
14 |
32 |
Hypermyope |
No |
Normal |
Soft |
15 |
39 |
Hypermyope |
Yes |
Reduced |
None |
16 |
34 |
Hypermyope |
Yes |
Normal |
None |
17 |
52 |
Myope |
No |
Reduced |
None |
18 |
51 |
Myope |
No |
Normal |
None |
19 |
50 |
Myope |
Yes |
Reduced |
None |
20 |
54 |
Myope |
Yes |
Normal |
Hard |
21 |
52 |
Hypermyope |
No |
Reduced |
None |
22 |
55 |
Hypermyope |
No |
Normal |
Soft |
23 |
58 |
Hypermyope |
Yes |
Reduced |
None |
24 |
54 |
Hypermyope |
Yes |
Normal |
None |
In: Math
In: Math
In: Math