jernplate8
2021-01-19
Answered

Explain the variation in summary statistics by substracting the dataset into the percent value of 49.23.

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Tasneem Almond

Answered 2021-01-20
Author has **91** answers

General condition:

If the data is being added or subtracted by the same value, there exist increasing or decreasing nature of value of arising in the measures of center and it leaves the measures of spread unchanged.

Interpretation:

The value 49.23 percent are subtracted from the predicted job growths for each rates, the mean and median also decreased by 49.23 and it leaves the standard deviation and the interquartile range remains constant(unchanged). There is no change in the measures of dispersion.

If the data is being added or subtracted by the same value, there exist increasing or decreasing nature of value of arising in the measures of center and it leaves the measures of spread unchanged.

Interpretation:

The value 49.23 percent are subtracted from the predicted job growths for each rates, the mean and median also decreased by 49.23 and it leaves the standard deviation and the interquartile range remains constant(unchanged). There is no change in the measures of dispersion.

asked 2021-01-19

Which of the following is not a condition for performing inference about a population mean U ?
A) Inference is based on n independent measurements.
B) The population distribution is Normal or the sample size is large (say n > 30).
C) The data are obtained from a SRS from the population of interest.
D) The population standard deviation, ? , must be known .

asked 2022-04-19

Solution verification for hypothesis testing and confidence interval problem

There's a random sample of size $n=10$ observations over a normally distributed population with standard deviation $\sigma =2$:

8.7, 7, 4, 7.6, 3, 8.1, 6.4, 6.1, 9.4, 6.2

- Find 96% confidence interval for the population mean

- Test the hypothesis ${H}_{0}:\mu =7.5$ against Ha: $\mu \ne 7.5$ with significance level $\alpha =0.01$. Find approximation of the observed p value.

My Solution:

We are looking for real numbers l and u s.t.:

$P\left(l<\hat{\theta}<u\right)=0.96$, where $\hat{\theta}=\frac{\sum _{i=1}^{n}{X}_{i}-n\theta}{\sqrt{n{\sigma}^{2}}}\sim N(0,1)$

We are looking for $z}_{0.2$ which from the z-score table is: 2.055. Therefore:

$-2.055<\frac{{\sum}_{i=1}^{n}{X}_{i}-n\theta}{\sqrt{n{\sigma}^{2}}}<2.055\equiv -2.055\sqrt{40}<\sum _{i=1}^{n}{X}_{i}-n\theta <2.055\sqrt{40}\equiv $

$\equiv \xad12.996-66.5<-10\theta <12.996-66.5\equiv 5.350<\theta <7.94.$

For the second part:

We set two z-scores: ${z}_{1}=-2.325\text{}\text{and}\text{}{z}_{2}=2.325$ from which we construct a two-tailed test.

Our test statistic is: $t=\frac{(6.65-7.5)\sqrt{10}}{2}=-1.343\Rightarrow t\ge -2.235$ from where we see the test statistic t is not in the rejection region, therefore we fail to reject the null hypothesis.

asked 2020-11-12

Given Vallias' value for ${\int}_{0}^{\sqrt{a}}{x}^{2}dx$ ,

calculate his value for${\int}_{0}^{a}\sqrt{x}dx,$ using graph.

calculate his value for

asked 2021-05-13

A boy is to sell lemonade to make some money to afford some holiday shopping. The capacity of the lemonade bucket is 1. At the start of each day, the amount of lemonade in the bucket is a random variable X, from which a random variable Y is sold during the day. The two random variables X and Y are jointly uniform.

Find and sketch the CDF and the pdf of Z which is the amount of lemonade remaining at the end of the day. Clearly indicate the range of Z

Find and sketch the CDF and the pdf of Z which is the amount of lemonade remaining at the end of the day. Clearly indicate the range of Z

asked 2022-01-17

Suppose that you get into a car accident at an average rate of about one accident every 3 years. In the next 21 years, you would expect to have about 7 accidents. if you actually had 5 accidents in that time, can you say that you're a better driver?

asked 2022-04-06

I'm trying to understand the functional form of the Generalized Pareto distribution (GPD). In the "Definition" section location parameter μ does not appear in the function, whilst in the "Characterization" section it does.

1. how the GPD form can be reconciled with GPD form presented in other sources. Derivation of the GPD from the Generalized Extreme Value (GEV) distribution would suggest that $\frac{x-\mu}{\sigma}$ should not appear in that form in the expression of the GPD.

1. how the GPD form can be reconciled with GPD form presented in other sources. Derivation of the GPD from the Generalized Extreme Value (GEV) distribution would suggest that $\frac{x-\mu}{\sigma}$ should not appear in that form in the expression of the GPD.

asked 2021-08-03

A poll asked the question, "What do you think is the most important problem facing this country today?" Twenty-five percent of the respondents answered "crime and violence." The margin of sampling error was plus or minus 3 percentage points. Following the convention that the margin of error is based on a $95\mathrm{\%}$ confidence interval, find a $95\mathrm{\%}$ confidence interval for the percentage of the population that would respond "crime and violence" to the question asked by the pollsters.

Lower limit$\mathrm{\%}$

Upper limit$\mathrm{\%}$

Lower limit

Upper limit