In an effort to counteract student cheating, the professor of a large class created four versions of a midterm exam, distributing the four versions among the 340 students in the class, so that each version was given to 85 students. After the exam, the professor computed the following information about the scores (the exam was worth 200 points): Sample Sample Sample size Group mean variance Version A 85 159.9 324.1 Version B 85 153.7 449.5 Version C 85 155.4 386.7 Version D 85 153.1 337.1 Send data to calculator Send data to Excel The professor is willing to assume that the populations of scores from which the above samples were drawn are approximately normally distributed and that each has the same mean and the same variance. Answer the following, carrying your intermediate computations to at least three decimal places and rounding your responses to at least one decimal place. (a) Give an estimate of this common population variance by pooling the sample variances given. (b) Give an estimate of this common population variance based on the variance of the sample means given. ?

Q: In the following scenarios identify the sample and variables for the study. A researcher wants to…

A: The population is the set of all objects which has the characteristics of the variable of interest…

Q: What is the mean for the following sample of scores? Scores: 1, 4, 5, 6 Question 3 options: 16 8 4.5…

A: We have given the following data1,4,5,6

Q: Find the first quartile for the scores on the Mathematics portion of the SAT.

A: Given that. X~N( μ=528, ?=117) μ=528 , ?=117

Q: third

A: Please refer to the image below

Q: Explain in your own words what it means that a sample must be representative of the population.…

A: To explain about sample and population and to choose the best fit for the study on students of the…

Q: Why is a sample proportion generally used to estimate a population proportion instead of obtaining…

A: Population proportion: The proportion that is calculated from the population which has a specific…

Q: How is a sample related to a​ population?

A: Population is set of all elements about which we want to know. While the sample is a part of such…

Q: Discuss the characteristics of the basic descriptive statistics: sample size, mean, and standard…

A: Characteristics of mean: Mean represents all the values of the data. Outliers of the data affects…

Q: A test consisting of 25 multiple choice questions with 5 answer choices for each question is…

A: X follows a Binomial distribution with n=25 and p=P(correct answer) = 1/5

Q: For each student in a study, demographic data are collected, including age, gender, and…

A: For each student in a study, we are collecting the demographic data including age, gender, and…

Q: There are six sisters and a family. Their ages are 7 years, 10 years, 15 years, 15 years, 20 years,…

A: Assume that the random variable x defines the ages of the sisters in the family.

Q: Explain how each portion of the ANOVA table is calculated, ultimately leading to the F statistic.

A:

Q: How can you make your sampling method more reliable? (English Translation: List a way you could make…

A: Introduction: Sampling is done in practical life instead of a population census, in most of the…

Q: In an Adecco staffing survey of 1000, adults in the US, 140 said the salary was the most important…

A: From the provided information, The sample size is 1000 which is sufficiently large and out of which…

Q: There are eight patients waiting in a doctor's waiting room. They have been waiting for 9 minutes,…

A: Given: Given data in minutes is: 2, 4, 5, 7, 8, 9, 11, 12

Q: What is Sample?

A:

Q: find sample mean and sd   4.5,8.5,6.0,8.2,4.5,6.3,8.4,5.3,9.1,2.5,6.0,7.5

A: We need to find sample mean and sd 4.5,8.5,6.0,8.2,4.5,6.3,8.4,5.3,9.1,2.5,6.0,7.5

Q: Does the population proportion and sample proportion always have the same value?

A: The question is about parametric inference.Introduction :Population proportion :The value of…

Q: In each part, give the value of the standardized statistic (z-score) for the sample proportion.…

A: The objective of the question is to calculate the z-score for the sample proportion in each of the…

Q: Explain the EFFECT OF SAMPLE SIZE.

A: The size of our sample defines how much information we have and thus, in part, decides our precision…

Q: What is the difference between Sample and Population? Provide an example of each.

A: Population -whole number of individuals Sample - a part of population taken randomly

Q: Explain about if larger the sample size, what does this reflects.

A:

Q: A newspaper infographic titled "Social Media Jeopardizing Your Job?" summarized data from a survey…

A: The following solution is provided below

Q: How to decide one or Two Samples?

A: t-test:  (i) In the t-test, the sample size of 30 is large enough (n < 30) (ii) Samples are taken…

Contingency Table

A contingency table can be defined as the visual representation of the relationship between two or more categorical variables that can be evaluated and registered. It is a categorical version of the scatterplot, which is used to investigate the linear relationship between two variables. A contingency table is indeed a type of frequency distribution table that displays two variables at the same time.

Binomial Distribution

Binomial is an algebraic expression of the sum or the difference of two terms. Before knowing about binomial distribution, we must know about the binomial theorem.