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78 . For a chi-square distribution with five degrees of freedom, the curve is ______________.

11.3: test of independence

Use the following information to answer the next four exercises. You are considering conducting a chi-square test of independence for the data in this table, which displays data about cell phone ownership for freshman and seniors at a high school. Your null hypothesis is that cell phone ownership is independent of class standing.

79 . Compute the expected values for the cells.

Cell = Yes Cell = No
Freshman 100 150
Senior 200 50

80 . Compute ( O E ) 2 z for each cell, where O = observed and E = expected.

81 . What is the chi-square statistic and degrees of freedom for this study?

82 . At the α = 0.5 significance level, what is your decision regarding the null hypothesis?

11.4: test of homogeneity

83 . You conduct a chi-square test of homogeneity for data in a five by two table. What is the degrees of freedom for this test?

11.5: comparison summary of the chi-square tests: goodness-of-fit, independence and homogeneity

84 . A 2013 poll in the State of California surveyed people about taxing sugar-sweetened beverages. The results are presented in the following table, and are classified by ethnic group and response type. Are the poll responses independent of the participants’ ethnic group? Conduct a hypothesis test at the 5% significance level.

Ethnic Group \ Response Type Favor Oppose No Opinion Row Total
White / Non-Hispanic 234 433 43 710
Latino 147 106 19 272
African American 24 41 6 71
Asian American 54 48 16 118
Column Total 459 628 84 1171

85 . In a test of homogeneity, what must be true about the expected value of each cell?

86 . Stated in general terms, what are the null and alternative hypotheses for the chi-square test of independence?

87 . Stated in general terms, what are the null and alternative hypotheses for the chi-square test of homogeneity?

11.6: test of a single variance

88 . A lab test claims to have a variance of no more than five. You believe the variance is greater. What are the null and alternative hypothesis to test this?

Practice test 3 solutions

8.1: confidence interval, single population mean, population standard deviation known, normal

1 . σ n = 4 30 = 0.73

2 . normal

3 . 0.025 or 2.5%; A 95% confidence interval contains 95% of the probability, and excludes five percent, and the five percent excluded is split evenly between the upper and lower tails of the distribution.

4 . z -score = 1.96; E B M =   z α 2 ( σ n ) = ( 1.96 ) ( 0.73 ) =   1.4308

5 . 41 ± 1.43 = (39.57, 42.43); Using the calculator function Zinterval, answer is (40.74, 41.26. Answers differ due to rounding.

6 . The z -value for a 90% confidence interval is 1.645, so EBM = 1.645(0.73) = 1.20085.
The 90% confidence interval is 41 ± 1.20 = (39.80, 42.20).
The calculator function Zinterval answer is (40.78, 41.23). Answers differ due to rounding.

7 . The standard error of measurement is: σ n =   4 50 = 0.57
E B M =   z α 2 ( σ n ) = ( 1.96 ) ( 0.57 ) =   1.12
The 95% confidence interval is 41 ± 1.12 = (39.88, 42.12).
The calculator function Zinterval answer is (40.84, 41.16). Answers differ due to rounding.

Questions & Answers

Frequency find questions
Rimsha Reply
What is nominal variable
olusola Reply
Write short notes on, nominal variable, ordinal variable, internal variable, ratio variable.
P( /x-50/ less than or equal to 5 ) where mean =52 and Variance =25
Jay Reply
how I get the mcq
Mukesh Reply
please what is data mining
Josephine Reply
the exploration and analysis of large data to discover meaningful patterns and rules
how do we calculate the median
All Reply
f(x)=cx(1-x)^4 as x range 4rm 0<=x<=1. Can someone pls help me find d constant C. By integration only..
Akeem Reply
uses of statistics in Local Government
Saleema Reply
state road transport corporation
District statistical officer
statistical services
Please is this part of the IMT program
testing of drugs
hii 2
How about population census
Hello every one
sample survey is done by local government in each and every field.
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that's true
statistics is one of the tool that represents the falling and rising of any cases in one sheet either that is in population census whether forecast as well as economic growth
statistic is a technique, and statistics is a subject
what is business statistics
PM Reply
Probability tells you the likelihood of an event happening. ... The higher the probability, the more likely it is to happen. Probability is a number or fraction between 0 and 1. A probability of 1 means something will always happen, and a probability of 0 means something will never happen...
La Reply
Saying it's a number between zero and one means it is a fraction so you could remove "or fraction" from you definition.
wouldn't be correct to remove fractions, saying a number is justified as probabilities can also be decimals between 0 and 1.
Saying "a number" will include it being a decimal which are themselves fractions in another form.
I will simply say a probability is a number in the range zero to one, inclusive.
How to delete an entry? This last one was a pocket print.
what is probability
sky-D Reply
chance of occurrence
what is data
Muhd Reply
raw facts and figures
information of any kind
What is Statistic
ibrahim Reply
what statistical analysis can i run on growth and yield of spinach.
format of the frequency distribution table
what is pearson correlation coefficient indicates?
Statistic is the mean of the sample.
can anyone determine the value of c and the covariance and correlation for the joint probability density function Fxy(x,y)=c over the range 0<x<5,0<y,and x-1<y<x-1.
what actually is the definition of range
Chinedu Reply
I need social statistics materials
the range of a set of data is the difference between the largest and smallest values
I need more explanation about cluster sampling
write the set of old number that are greater than or equal to minutes 7 butl less than 5 in both of the set notation
Jerry Reply

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