Bruce Partridge
2022-03-01
Answered

A random sample of n = 15 items are selected for measurement. Nothing is known about the distribution of measurements. Are the requirements for constricting a confidence interval for the population mean satisfied? Explain in 1 - 2 complete sentences.

You can still ask an expert for help

faraidz3i

Answered 2022-03-02
Author has **10** answers

Introduction:

The sample size considered here is, n = 15.

Explanation:

It is of interest to construct a confidence interval for the population mean measurement.

Now, an unbiased point estimate for the population mean is the sample mean. As a result, the confidence interval is constructed using the sample mean, its standard error, and a confidence level. The construction of the confidence interval for the population mean requires the basic assumption of at least an approximate normal distribution of the variable of interest.

The sampling distribution of the sample mean,

If the sample size is large

In this case, no information is available regarding the distribution of the measurements. As a result, it cannot be said that the measurements are normally distributed.

Further, the sample size of n = 15 is not large. Thus, it is not possible to assume even an approximate normal distribution.

Thus, the requirements for constructing a confidence interval for the population mean are not satisfied.

Miles Martin

Answered 2022-03-03
Author has **6** answers

It helped a lot)

asked 2022-03-03

1. A data set consists of the ages at death for each of the 41 past presidents of United States.

2. Is this set of measurement a population or a sample?

a. What is the variable being measured?

b. What measurement scale is appropriate for the data?

2. Is this set of measurement a population or a sample?

a. What is the variable being measured?

b. What measurement scale is appropriate for the data?

asked 2022-04-12

At work, there is a statistical process going on, which I feel is probably mathematically incorrect but can't quite put my finger on what is wrong:

They are totalling up the number of hours people work per week (in minimum units of 15 minutes), and then producing averages for the whole department per week. Obviously, the results come out to be non-integer numbers of hours with a long number of decimals.

Then, they are judging the result of certain productivity-boosting techniques and displaying the findings in "minutes gained/lost"...in some cases producing productivity gains of as little as a minute or two minutes per week.

So to summarise, they are calculating units of quarters of an hour, but then presenting the average productivity gains in minutes...is this presuming an accuracy which is not present in the initial measurement? I think it is, but don't know how to argue it to my boss.

They are totalling up the number of hours people work per week (in minimum units of 15 minutes), and then producing averages for the whole department per week. Obviously, the results come out to be non-integer numbers of hours with a long number of decimals.

Then, they are judging the result of certain productivity-boosting techniques and displaying the findings in "minutes gained/lost"...in some cases producing productivity gains of as little as a minute or two minutes per week.

So to summarise, they are calculating units of quarters of an hour, but then presenting the average productivity gains in minutes...is this presuming an accuracy which is not present in the initial measurement? I think it is, but don't know how to argue it to my boss.

asked 2022-04-02

The following appear on a physician's intake form. Identify the level of measurement of the data.

(a) Disabilities

(b) Change in health (scale of -5 to 5)

(c) Year of birth

(d) Height

(a) What is the level of measurement for "Disabilities"?

Interval

Nominal

Ratio

Ordinal

(b) What is the level of measurement for "Change in health (scale of - 5 to 5)"?

Ratio

Nominal

Ordinal

Interval

(c) What is the level of measurement for "Year of birth"?

Interval

Ordinal

Nominal

Ratio

(d) What is the level of measurement for "Height"?

Nominal

Interval

Ordinal

Ratio

(a) Disabilities

(b) Change in health (scale of -5 to 5)

(c) Year of birth

(d) Height

(a) What is the level of measurement for "Disabilities"?

Interval

Nominal

Ratio

Ordinal

(b) What is the level of measurement for "Change in health (scale of - 5 to 5)"?

Ratio

Nominal

Ordinal

Interval

(c) What is the level of measurement for "Year of birth"?

Interval

Ordinal

Nominal

Ratio

(d) What is the level of measurement for "Height"?

Nominal

Interval

Ordinal

Ratio

asked 2022-04-03

Suppose the current measurements made on a conductor wire track follow a normal distribution with mean 10 milliamperes and variance 4 (milliamperes)^2

a) what is the probability that the value of a measurement is less than 9 milliamperes?

b) what is the probability that the value of a measurement is greater than 13 milliamps?

c) what is the probability that the value of a current measurement is between 9 and 11 milliamperes?

a) what is the probability that the value of a measurement is less than 9 milliamperes?

b) what is the probability that the value of a measurement is greater than 13 milliamps?

c) what is the probability that the value of a current measurement is between 9 and 11 milliamperes?

asked 2021-02-12

An ore loader moves 1200 tons/h from a mine to the surface. Convert this rate to lb/s, using 1 ton 2000 lb.

asked 2022-03-31

Suppose your weight is 53.81 kilograms. A scale at a health clinic gives your weight as 54.4 kilograms. A digital scale at the gym that gives readings to the nearest 0.01 kilogram gives your weight as 54.19 kilograms. Which measurement is more precise? Which is more accurate?

Which measurement is more precise? Choose the correct answer below.

A. The digital scale at the gym is more precise.

B. The health clinic scale is more precise.

Which measurement is more accurate? Choose the correct answer below.

A. The digital scale at the gym is more accurate.

B. The health clinic scale is more accurate.

Which measurement is more precise? Choose the correct answer below.

A. The digital scale at the gym is more precise.

B. The health clinic scale is more precise.

Which measurement is more accurate? Choose the correct answer below.

A. The digital scale at the gym is more accurate.

B. The health clinic scale is more accurate.

asked 2022-05-15

For random variables $X,Y$, I need to show that if $X,Y$ are independent, then $E(Y\mid X)=E(Y)$. To do so, it suffices to prove that for any $B\subseteq \mathbb{R}$ measurable (Borel), we have that

${\int}_{X\in B}EYdP={\int}_{X\in B}YdP$

I know that ${\int}_{X\in B}EYdP=EYP(X\in B)$ - but how do I show that ${\int}_{X\in B}YdP=EYP(X\in B)$?

${\int}_{X\in B}EYdP={\int}_{X\in B}YdP$

I know that ${\int}_{X\in B}EYdP=EYP(X\in B)$ - but how do I show that ${\int}_{X\in B}YdP=EYP(X\in B)$?