Students often incorrectly use the term "bias" to describe anything that is wrong with a research study, saying, "the study is biased because . . ." But Sampling Bias and the presence of a Confounding Variable are two different problems for research, that prevent different types of conclusions, that have different remedies to remove them from a study when it is designed. This discussion is designed for students to help each other build a complete understanding, and clearly separate these as two distinct concepts. Discuss the similarities and differences between these, as well as the research problems they cause, and how they can be eliminated from a study.

Q: When conducting a One-Way Analysis of variance, what option on the LSMEANS statement requests a…

A: Given information: The researcher is specially interested in conduction One-Way ANOVA.

Q: If the null hypothesis is true, this means that there is no real difference between sample means and…

A: If the null hypothesis is true, this means that there is no real difference between sample means and…

Q: In the digital age of marketing, special care must be taken to make sure that programmatic ads…

A: (a). Test for significant differences in perception among the three groups: There are 3 groups. The…

Q: n the digital age of marketing, special care must be taken to make sure that programmatic ads…

A: Anova: Single Factor                   SUMMARY         Groups Count Sum Average Variance…

Q: If we delete the largest observation from a sample, then the sample mean and variance will both be…

A: The mean is the average of a group of numbers, and the variance measures the average degree to which…

Q: For a repeated measures study, if the null hypothesis is true, then what value should be obtained…

A: According to the provided information, the null hypothesis is true

Q: What are the conclusions of the study?

A: Parametric test is used to determine the mean significance between the sample and population when…

Q: 4) Many smartphones, especially those of the LTE-enabled persuasion, have earned a bad rap for…

A: a)To test:H0:σ12=σ22H0:σ12>σ22 where σ12 and σ22 are the population variances of battery usage on…

Q: Although, in practice, sample data are generally analyzed in inferential studies, what is the…

A: If the data consists of different methods for estimating the sample and drawing the inferences about…

Q: If you have a sample size of 100 from a population of rope with sample mean breaking strength of 960…

A: Solution: Let X be the breaking strength. From the given information, x-bar = 960 pounds, S=200…

Q: When conducting a retrospective cohort study what are some possible selection and information bias…

A: The study is categorised into 2 Prospective cohort study Retrospective cohort study Prospective…

Q: If you want to reduce the amount of variance present in an independent-measures (one-way) ANOVA, you…

A: ANOVA is a parametric inferential procedure.

Q: . When an accurate and complete list of the population is not available, a sampling will suffer…

A: We want to tell you, which one is the correct choice.

Q: Since the sample size is always smaller than the size of the population, the sample mean O A. can be…

A: Correct answer is (A)

Q: If you want to reject the null hypothesis, which should be larger, the within groups or between…

A: We have given that a statement related to null hypothesis in case of F test.

Q: In your own words, give a simple explanation on why statisticians think the sample variance is…

A: We can define the bias of an estimator as the difference between this estimator's expected…

Q: A. If the results were statistically significant, can the results of this study be generalized to a…

A: The study involved 350 volunteers over the age of 60 years. Each subject was assigned to a treatment…

Q: an independent-samples t test, you will usuall

A: the test statistic for independent-samples t test = μ1-μ2-0combined standard deviation

Q: Discuss the measures of central tendencies and the situations in which one is a better…

A: The 3 most common measures of central tendency are the mean, median and mode. 1) Mean: Or we can…

Q: If you calculate the sample covariance between two variables X and Y equals one, then there must be…

A:

Q: If the difference in means of two data sets is not zero, does that imply that on average the two…

A: In this we need to find whether the difference in means of two data sets is not zero, the does it…

Q: In the digital age of marketing, special care must be taken to make sure that programmatic ads…

A: a) Null Hypothesis: H0: There is no differences in the perceptions for marketing managers, marketing…

Q: er, which type of statistical test is most appropriate?

A: There are various statistical test that can help in exploring the relationship between two…

Q: Does the shape or color of a pain pill influence its effectiveness?  Although logically it…

A: Given Information: Four groups of adult patients were given the same amount of Advil after dental…

Q: what kind of statistical data might a barglar alarm company employ in trying to convince urdban…

A: Statistical Data: By statistical data, we mean the factual material used as a basis for discussion…

Q: A researcher is testing the effect of one independent variable using three treatment conditions. She…

A: Given that, A researching is testing the effect of one independent variable using three treatment…

Q: If the variability between the different sample means taken from the same population is small, we…

A: If the variability between the different sample means taken from the same population is small, we…

Q: Dr. Guidry conducts a study examining the relationship between the number of friends one has and the…

A: Given Information: Dr Guidry is interested in examining the relationship between the number of…

Q: If you are running a hypothesis test and increase your sample size, what will happen to your Type I…

A: Higher sample makes higher power of test And smaller sample makes small the power of test

Q: The term clinical means that the study involves people.  True  False

A: Given, The term clinical means that the study involves people.

Q: n the digital age of marketing, special care must be taken to make sure that programmatic ads…

A: Since we only answer up to 3 sub-parts, we’ll answer the first 3. Please resubmit the question and…

Q: One of the objectives of a well-designed experiment is to reduce variability O True O False

A:

Q: In the digital age of marketing, special care must be taken to make sure that programmatic ads…

A: (a). Test for significant differences in perception among the three groups: There are 3 groups. The…

Q: Why is it wrong to say that sampling bias is unavoidable?

A: Bias is error. Sampling bias is due to taking a fraction of the population not the entire…

Q: What is omitted variable bias?

A: The omitted variable bias is very useful concept in the statistics. A type of the selection bias…

Q: When a questionnaire is too long and an individual only answers half of the questions, this…

A: Respondent's subconscious reaction

Q: An analysis of variance produces SSb = 40 and MSb = 20.  In this analysis, how many treatment…

A: Let k be the number of treatments Given that SSb = Between sum of squares = 40 MSb = Between mean…

Q: In almost all research studies, data are obtained from samples. A. True в. False

A: In almost all the research studies ,data are obtained from the samples  True  False

Q: If other factors are held constant, increasing the sample variances will have very little influence…

A: Effect size : The size of the effect indicates how significant the association between variables or…

Q: Judge and Cable (2010) found that thin women had higher incomes than heavier women. Is this an exam-…

A: Exp study involves manipulation of control variable. Non exp study doesn't involve manipulation of…

Q: If the null hypothesis is true, then what does the distribution of sample means?

A: Null Hypothesis: A hypothesis which is tested for plausible rejection is called the Null Hypothesis…

Q: When comparing test scores of two groups, a difference of one point would never be highly…

A: In testing of hypothesis, the sample size doesn’t influence the result of the test.

Q: Discuss the basic strategy for performing a hypothesis test to compare the means of two populations,…

A: In two sample t test, there are two independent large samples taken from two different populations.

Q: It states that there is significant difference between the observed and expected data.

A: Alternative Hypothesis

Q: If the underlying population of study is not normally distributed, how large should the sample size…

A: Introduction: Define X as the random variable of interest here. Suppose that X has a distribution…

Q: One advantage of a within subjects ANOVA is that the participants serve as their own comparisons…

A: Here we want to know given statement is correct or not.

Q: The area of inferential statistics called hypothesis testing is a decision-making process for…

A: Introduction: Inferential statistics is the branch of statistics, that is involved in making…

Confidence Intervals

When we calculate intervals in probability and statistics, it can be simply termed as finding out a confidence interval. The confidence interval is usually calculated from the data set which is observed. The value of the parameter that needs to be calculated is present here only.