Skip to main content
Ch. 1 - Introduction to Statistics
Triola - Elementary Statistics 14th Edition
Triola14th EditionElementary StatisticsISBN: 9780137366446Not the one you use?Change textbook
Chapter 1, Problem 1.CQQ.7

Birth Weights Refer to the sample described in Exercise 6. Because Bellevue Hospital Center agreed to provide the 100 birth weights, does the sample of birth weights constitute a voluntary response sample?

Verified step by step guidance
1
Understand the concept of a voluntary response sample: A voluntary response sample is one where participants choose to be part of the sample. This often leads to bias because those who choose to respond may have different characteristics than those who do not.
Identify how the sample was obtained: In this case, Bellevue Hospital Center provided the birth weights. This suggests that the sample was not obtained by asking individuals to volunteer their birth weights.
Determine if the sample is voluntary: Since the hospital provided the data, the individuals whose birth weights are included did not volunteer their information. Therefore, this is not a voluntary response sample.
Consider the implications of the sampling method: Since the sample is not voluntary, it is less likely to be biased in the way voluntary samples often are. However, consider other potential biases, such as selection bias, if the sample is not representative of the broader population.
Reflect on the importance of sample type: Understanding the type of sample is crucial for interpreting the results and generalizing findings. A non-voluntary sample like this one may provide more reliable insights into the population of interest.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Voluntary Response Sample

A voluntary response sample is a type of non-probability sampling where participants self-select into the sample. This often leads to bias, as those who choose to participate may have different characteristics compared to those who do not. In the context of the question, understanding whether the birth weights were self-reported or selected by the hospital is crucial to determine if the sample is voluntary.
Recommended video:
05:11
Sampling Distribution of Sample Proportion

Sampling Bias

Sampling bias occurs when certain members of a population are more likely to be included in a sample than others, leading to a sample that is not representative of the population. In the case of birth weights, if the sample is voluntary, it may not accurately reflect the general population's birth weights, thus affecting the validity of any conclusions drawn.
Recommended video:
05:11
Sampling Distribution of Sample Proportion

Representative Sample

A representative sample accurately reflects the characteristics of the population from which it is drawn. It is crucial for making valid inferences about the population. In this scenario, determining whether the birth weights provided by Bellevue Hospital Center form a representative sample is essential to ensure that any analysis or conclusions are applicable to the broader population.
Recommended video:
05:11
Sampling Distribution of Sample Proportion
Related Practice
Textbook Question

Physicians’ Health Study In the Physicians’ Health Study, some of the subjects were treated with aspirin while others were given a placebo. For the subjects in this experiment, what is blinding?

272
views
Textbook Question

Determining Sample Size The given expression is used to determine the size of the sample necessary to estimate the proportion of college students who have the profound wisdom to take a statistics course. Find the value and round the result up to the next larger whole number.


[(1.95996)^2 - 0.25] / (0.03)^2

327
views
Textbook Question

Survey Which of the following best describes the level of measurement of the numbers 1, 2, 3, . . . , 410 described in Exercise 1: nominal, ordinal, interval, ratio?

344
views
Textbook Question

IQ Scores Listed below are the IQ scores of randomly selected statistics professors. What value is obtained when those IQ scores are added and the total is divided by the number of scores? (This result, called the mean, is discussed in Chapter 3.) What is notable about these values?


135 149 145 129 118 119 115 133 107 188

240
views
Textbook Question

Birth Weights For 100 randomly selected births from Bellevue Hospital Center, the birth weights are added and then divided by 100. The result is 3240 g. Is the value of 3240 g a statistic or a parameter?

294
views
Textbook Question

Standard Deviation One way to get a very rough approximation of the value of a standard deviation of sample data is to find the range, then divide it by 4. The range is the difference between the highest sample value and the lowest sample value. In using this approach, what value is obtained from the sample data listed in Exercise 1 “IQ Scores”?

368
views