Preview

Using a Sample to Draw an Inference about a Population

Satisfactory Essays
Open Document
Open Document
550 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Using a Sample to Draw an Inference about a Population
What does it mean to say that we are going to use a sample to draw an inference about a population? | |
|Why is a random sample so important for this process? If we wanted a random sample of students in a cafeteria, why couldn’t we |
|just take the students who order Diet Pepsi with their lunch? |
|Comment on the statement, “A random sample is like a miniature population, wheras samples that are not random are likely to be |
|biased.” |
|Why would the students who order Diet Pepsi with lunch not be a random sample of students in the cafeteria? |

A population may be a large collection of people, objects, or measurements that we are interested in analyzing. However, it may not be practical to draw our inference using the entire population. In the case that it is not practical to draw a conclusion using the entire population, we will use a sample. For example, if I was conducting an analysis of the marital status of all women in the United States, it may be impractical to contact every single woman living in the Unites States. I would then contact a sample of women in the United States; I may contact 5,000 women and these 5,000 women would serve as my sample of all woman. I would then draw an inference about the marital status of women in the United States based on the sample. A random sample is very important for the process of sampling. A random sample is important because this type of sample will be representative of the entire population. Randomly choosing the sample from a population will allow for accurate results of the conclusion. If we wanted a random sample of students in a cafeteria we could not just take the students who order Diet Pepsi with their lunch because this sample would not be a random sample of a population. If we were to

You May Also Find These Documents Helpful

  • Satisfactory Essays

    Our new sample consists of a random selection of representatives, from ten randomly chosen states. We think that selecting individual at random will ensure that every representative in the customer service population will have an equal opportunity of being selected for the sample. Overall, acquiring a genuine random sample will eliminate any possibilities of bias conclusions.…

    • 425 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    Ch 5 Exercises Solutions

    • 8101 Words
    • 33 Pages

    5.2 WHAT IS THE POPULATION? For each of the following sampling situations identify the population as exactly as possible. That is, say what kind of individuals the population consists of and say exactly which individuals fall in the population. If the information given is not complete, complete the description of the population in a reasonable way. (a) Each week, the Gallup Poll questions a sample of about 1500 adult U. S. residents to determine national opinion on a wide variety of issues. An individual is a person; the population is all adult U.S. residents. (b) The 2000 census tried to gather basic information from every household in the United States. But a “long form” requesting much additional information was sent to a sample of about 17% of households. An individual is a household; the population is all U.S. households. (c) A machinery manufacturer purchases voltage regulators from a supplier. There are reports that variation in the output voltage of the regulators is affecting the performance of the finished products. To assess the quality of the supplier’s production, the manufacturer sends a sample of 5 regulators from the last shipment to a laboratory for study. An individual is a voltage regulator; the population is all the regulators in the last shipment.…

    • 8101 Words
    • 33 Pages
    Good Essays
  • Good Essays

    Qnt 561 Week2

    • 1289 Words
    • 6 Pages

    For example, if I want to know how watching the violent shows on television affects the behavior of children, it won’t be realistic to study each child in the population, so I would use sampling.…

    • 1289 Words
    • 6 Pages
    Good Essays
  • Powerful Essays

    Other Terms Population: entire group of people being studied Sample: the part of the population being studied Inference: conclusion made about the population based on the sample Binary Data: only 2 choices/outcomes Non-Binary: more than 2 outcomes Sampling Techniques Characteristics of a good sample -Each person must have an equal chance to be in the sample -Sample must be vast enough to represent Simple Random: each member has equal chance of being selected Ie, picking members randomly apartments Sequential Random: go through population sequentially and select members Ie, Selecting every 5th person Stratified Sampling: a strata is a group of people that share common charactoristics Constraints the proportion of members in the strata from the population in the sample…

    • 2372 Words
    • 10 Pages
    Powerful Essays
  • Good Essays

    statistics GCU

    • 2646 Words
    • 11 Pages

    Explain the importance of random sampling. What problems/limitations could prevent a truly random sampling and how can they be prevented?…

    • 2646 Words
    • 11 Pages
    Good Essays
  • Good Essays

    Siop Lesson Plan

    • 856 Words
    • 4 Pages

    CCSS.Math.Content.7.SP.A.2 Use data from a random sample to draw inferences about a population with an unknown characteristic of interest. Generate multiple samples (or simulated samples) of the same size to gauge the variation in estimates or predictions. For example, estimate the mean word length in a book by randomly sampling words from the book; predict the winner of a school election based on randomly sampled survey data. Gauge how far off the estimate or prediction might be.…

    • 856 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    dq 1 module one

    • 585 Words
    • 2 Pages

    The importance of Random sampling is that it gives a sense of equality. Each person has the same probability of being chosen as their neighbor. This sampling is trying to represent the whole population. Since it is unlikely that the research could get to everyone in the population the sampling must occurring in an accessible population, which is represented as the entire population. “Without random sampling strategies, the researcher, who has a vested interest in the study, will tend (consciously or unconsciously) to select subjects whose conditions or behaviors are consistent with the study hypotheses,” (Burns, N. & Grove, S. (2011). Through obtaining a random sampling “researchers leave the selection to chance, thereby increasing the validity of their studies,” (Burns, N. & Grove, S. (2011).…

    • 585 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Sqqs

    • 494 Words
    • 2 Pages

    | A population is a group of samples that may or may not be included in a study.…

    • 494 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    The core of biostatistics consists of the definition of a population and sampling, as they are the indicators of the fundamental concepts that are essential to understanding the statistics of the life and health sciences. The idea that a sample is illustrative of a given population, since a sample is derived from a specific, yet larger pool of information seems factually representative. Random sampling aides research in that it applies experimental design to the selection process and is the fairest means of sample collection, providing equal chance to the members of a given population being signified.…

    • 855 Words
    • 4 Pages
    Good Essays
  • Powerful Essays

    A population is the entire group to be studied and a sample is a portion of the population.…

    • 3045 Words
    • 13 Pages
    Powerful Essays
  • Good Essays

    A random sample: is a sample that fairly represents a population because each member has an equal chance of inclusion. Random sampling is the best technique for gathering survey data.…

    • 1431 Words
    • 6 Pages
    Good Essays
  • Good Essays

    Sampling methods

    • 718 Words
    • 3 Pages

    Probability sampling is a type of sampling that includes random selection. And in order to achieve random selection, it must be made sure that different units of population have equal probability of being chosen.…

    • 718 Words
    • 3 Pages
    Good Essays
  • Satisfactory Essays

    Cafs irp

    • 440 Words
    • 2 Pages

    Sampling is that part of statistical practice concerned with the selection of an unbiased or random subset of individual observations…

    • 440 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    Sociology Study Guide

    • 1345 Words
    • 6 Pages

    Random sample – A sample in which everyone in the target population has a chance of being selected in the study.…

    • 1345 Words
    • 6 Pages
    Powerful Essays
  • Good Essays

    The purpose of sampling is that if a researcher decides to research a group, a group can be very large that the information obtained may not be completely accurate. A researcher can get better information by breaking down the groups into smaller groups and researching them (Monette, 2011). An example of sampling in this case is the large group would be people with PTSD and it can be broken down smaller like researching veterans with PTSD. By breaking the group down for sampling, the data can be obtained more quickly and it is a feasible way of collection. There are types of sampling called probability and nonprobability.…

    • 908 Words
    • 3 Pages
    Good Essays