Assignment_07 pdf

Absenteeism:  Absenteeism can be a serious employment problem.  It is estimated that absenteeism reduces potential output by more than 10%.  Two economists launched a research project to learn more about the problem.  They randomly selected 100 organizations to participate in a 1-year study.  For each organization, they recorded the average number of days absent per employee and several variables thought to affect absenteeism.  The file ‘absenteeism FinEx’ contains the data on these selected 100 organizations. Clearly write the linear regression equation below without using X’s and Y’s.  Interpret the slope coefficient for wage based on this MLR model.

Absenteeism:  Absenteeism can be a serious employment problem.  It is estimated that absenteeism reduces potential output by more than 10%.  Two economists launched a research project to learn more about the problem.  They randomly selected 100 organizations to participate in a 1-year study.  For each organization, they recorded the average number of days absent per employee and several variables thought to affect absenteeism.  The file ‘absenteeism FinEx’ contains the data on these selected 100 organizations. Question: How does the MLR analysis compare with the t-test for Av Shift in predicting absenteeism?  Comment on the similarities and/or differences. (both MLR and t-test are provided below) Data: Wage Pct PT Pct U Av Shift U/M Rel Absent 22477 8.5 57.1 1 1 5.4 29939 1.9 41.5 0 1 4.1 22957 12.2 52.6 1 0 11.5 18888 30.8 65.1 0 1 2.1 15078 6.8 68.8 0 1 5.9 15481 5.1 46.4 0 0 12.9 21481 25.3 38.9 0 1 3.5 29687 9.2 17.2 0 0 2.6 13603 8.4 12.9 0 0 8.6 18303 4.9…

Student Absences and Grades on the Final Exam Dr. V. noticed that the more frequently a student is late or absent from class the worse he or she performs on the final exam. He decided to investigate. Dr. V. collected a random sample of 22 students. This sample includes the number of times a student is absent and their grades on the final exam. The data can be found in the Excel file Assignment10_R1.xlsx on the Exercise1_Excel_Built-in f. worksheet. Do not use any software that I did not assign. Question 1: Which or the two variables (times absent or grades on the final exam) is the independent variable and which is the dependent variable?     Question 2: Using Microsoft Excel: (Excel file Assignment10_R1.xlsx on the Exercise1_Excel_Built-in f.xlsx worksheet) Count the number of XY variables.   Calculate the mean and sample standard deviation of both the independent and dependent variables.         Calculate the correlation coefficient, r, using Excel’s CORREL function. Explain…

Student Absences and Grades on the Final Exam Dr. V. noticed that the more frequently a student is late or absent from class the worse he or she performs on the final exam. He decided to investigate. Dr. V. collected a random sample of 22 students. This sample includes the number of times a student is absent and their grades on the final exam. The data can be found in the Excel file Assignment10_R1.xlsx on the Exercise1_Excel_Built-in f. worksheet. Do not use any software that I did not assign. Calculate the correlation coefficient, r, using Excel’s CORREL function. Explain what it means.     Calculate the coefficient of determination, r2, using Excel’s RSQ function. Explain what it means..

Student Absences and Grades on the Final Exam Dr. V. noticed that the more frequently a student is late or absent from class the worse he or she performs on the final exam. He decided to investigate. Dr. V. collected a random sample of 22 students. This sample includes the number of times a student is absent and their grades on the final exam. The data can be found in the Excel file Assignment10_R1.xlsx on the Exercise1_Excel_Built-in f. worksheet. Do not use any software that I did not assign. : Using Excel, conduct a NHST to determine whether there is a correlation in the population. Use a 0.05 significance level. Use the Excel file Assignment10_R1.xlsx, Exercise1_Correlation NHST worksheet) Test Set-Up: What type of Null Hypothesis Test should you use? It this a left-tailed, two-tailed, or right-tailed test.       Significance Level: Use a 5% significance level. What is/are the Critical Value(s)?       Write the Null & Alternate Hypotheses (Follow the examples shown in…

Firefighter Fatalities Listed below are the numbers of heroic firefighters who lost their lives in the United States each year while fighting forest fires. The numbers are listed in order by year, starting with the year 2000. What important feature of the data is not revealed by any of the measures of center? https://media.cheggcdn.com/study/ce4/ce4078ad-f983-490e-9829-73a40e777080/721260-3.1-14IBSC1.png

Suggest suitable univariate data analysis that can be used to help the researcher to make an effective decisions.

Find the variance of these data 20,30,15, 18,22 (2 Points)

Look at the MS Excel file (titled “Easy_Tough”) available in the Blackboard. This file carries data about average MathSAT scores of 297 colleges and universities located in the USA and they are all classified into two groups of colleges and universities. One group of institutions are tough to graduate for students and another group of institutions are easy to graduate for students. Using MS Excel, perform analysis of variance test to examine whether the mean MathSAT score between these two groups are same or not.  this is the data on excel Easy to graduate colleges Tough to graduate colleges 547 495 550 526 451 480 470 533 617 429 554 529 524 568 620 550 650 535 519 506 486 540 494 509 513 459 615 526 524 377 525 543 608 490 537 513 550 466 520 544 540 502 497 480 520 531 533 470 455 400 525 494 603 395 578 445 459 460 525 372 575 504 564 480 509 520 530 542 670 522 590 440 590 510 532 419 585 330 514…

Using the data set provided in this lesson, the scores from the variable 'Life satisfaction' were found to be skewed at several time points, and given the relatively small sample size, you decide to run a non-parametric test to determine if there was a difference in median life satisfaction score at baseline (variable code = Life satisfaction_base), six months (variable code = Life satisfaction_6months) and one year (variable code = Life satisfaction_1 year). What statistical test would you use? a. Mann Whitney b. Wilcoxon Signed Rank C. Kruskal Wallis d. Friedman's test

Which regression model (linear vs decision tree) has the lowest mean absolute error? Linear regression Decision tree

Statistics students in Oxnard College sampled 11 textbooks in the Condor bookstore and recorded the number of pages in each textbook and its cost. The data are shown below: Number of Pages (xx) Cost(yy) 562 68.2 501 62.1 864 109.4 317 37.7 921 110.1 758 88.8 304 39.4 972 120.2 306 48.6 779 89.9 944 116.4 ˆyy^ =  xx + . (Please show your answers to two decimal places) Use the model to estimate the cost when number of pages is 694.Cost = $ (Use the linear model with yor rounded coefficients and then round your answer to 2 decimal places.)

What statistic would you use if you had one independent variable ‘geographic location’ (North, South, East, West), and one dependent variable ‘satisfaction with living environment’ (Yes, No)? Explain why.

What are the assumptions for a paired difference experimental design?

please explain thoroughly the Test of Homogeneity of Variances and Why Post Hoc Tukey HSD is the appropriate model. thanks

During the exam you will be using a sample of 500 adults with the following variables: genhelf - variable recording general self-reported health coded 1 = very good, 2 = good, 3 = fair, 4 = poor sbp - variable recording systolic blood pressure •age - age of the respondent in years • sex-coded 1 = male and 2 = female hi_sbp - indicator of high blood pressure coded 1 if the respondent's sbp is 130 or higher and 0 otherwise ● . What type of chart is MOST appropriate for showing the relationship between the variables sbp and age? O clustered bar chart O multiple pie charts O box and whisker plot (by categories) scatterplot

The results of a common standardized test used in psychology research is designed so that the population mean is 105 and the standard devlation is 30. A subject earns a score of 108. What is the Z-score for this raw score? Z-Score =

The number of awards earned by students at one high school is recorded. Predictors of the number of awards earned include the type of program in which the student was enrolled (e.g., vocational, general or academic) and the score on their final exam in math. Variables Participant number (ID) Number of awards Program type (vocational - 1; general - 2; academic - 3 Math Score   What is the level of measurement for the four variables (num_awards, prog, and math

You are going to think of a study that can be analyzed with an ANOVA.This is your chance to create your own examples that relate to your interests/careers. Ex: Sociology EX provided:  Hypothesis: dog breed and amount of sleep: bulldogs will sleep longer than both chihuahuas and golden retrievers, there will be no difference in the amount of sleep between chihuahuas and golden retrievers Independent Variable: brand (levels: bulldogs, chihuahuas, golden retrievers) notice the independent variable has 3 levels Dependent Variable: how many hours the dogs sleep   PLEASE BE SPECIFIC LIKE THE EXAMPLE. THANKS

Distinguished Between primary and secondary data

Estimate can be used to identify two general features for each of the several variance estimates in ANOVA. What are these features?

Generate two set of data of at least with ten data points using any scenario of your choice,Using the six steps of hypothesis test if there is difference in the mean and the proportion?2. Generate at least three set of data at least with ten data points using any scenario of your choice. Test if there is difference in their variances

Males under the age of 25 must pay far higher auto insurance premiums than females in this age group. How does this fact relate to statistical discrimination? Statistical discrimination implies that discrimination can persist indefifinitely, while the taste-for-discrimination model suggests that competition might reduce discrimination in the long run. Explain the difference.

Estimate sensitivity, specificity, positive predictive value, negative predictive value and prevalence from data in the 2 x 2 table for an infectious disease and its diagnostic test.

Explain Comparison of the Mean of Two Populations Overview cosidering Z-Test?

Which are the steps involved in the construction of explanatory bivariate tables?

Consider trying to predict the life expectancy of citizens in a country based on the birth rate (per 1000 people) in that country. Here is a scatterplot of the data from a random sample of 50 countries. > ggplot (SampCountries, aes (BirthRate, LifeExpectancy)) + geom_point (color = "darkred")+ labs (title = "Life Expectancy by Birth Rate") + Life Expectancy by Birth Rate 80 - 70 - 10 20 30 40 BirthRate Here is (some of) the R output for the linear model for this data. > LifeBirth.lm summary (LifeBirth. lm) Call: Im (formula = LifeExpectancy BirthRate, data = SampCountries) Residuals: Min 10 Median 30 Маx -7.0592 -2.3047 0.9123 2.5019 5.8358 Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) 85.26295 1.03301 82.54 BirthRate -0.63291 0.04492 -14.09 Residual standard error: 3.424 on 48 degrees of freedom Multiple R-squared: 0.8053, Adjusted R-squared: 0.8012 F-statistic: 198.5 on 1 and 48 DF, p-value: < 2.2e-16 LifeExpectancy

Cardiovascular Disease Left ventricular mass (LVM) is an important risk factor for subsequent cardiovascular disease. A study is proposed to assess the relationship between childhood blood-pressure levels and LVM in children as determined from echocardiograms. The goal is to stratify children into a normal bp group (< 80th percentile for their age, gender, and height) and an elevated bp group (≥ 90th percentile for their age, gender, and height) and compare change in LVM between the two groups. Before this can be done, one needs to demonstrate that LVM actually changes in children over a 4-year period. To help plan the main study, a pilot study is conducted where echocardiograms are obtained from 10 random children from the Bogalusa Heart Study at baseline and after 4 years of follow-up. The data are given in Table 9.18 9.67 What is the test statistic for this test as applied to the data in Table 9.18? Hint: Assume that the large sample method of significance testing is valid for…

A tutorial school has been running IELTS mock examination for many years. Below is the summary presented by the tutorial school related to the IELTS mock examination in one of the many online classes selected randomly in year 2022. IELTS score in mock examination Number of students <4 0 5 2 6 5 7 15 8 10 9 3 A report presented by this tutorial school 5 years ago indicated that the population mean score of IELTS mock examination was 7.05 points and the population proportion of students got 7 points or above was 0.67. (a)  Construct a 95% confidence interval estimate of population mean score a student get in the IELTS mock examination in 2022. (b)  Test, at 1% level of significance, if the population proportion of students get 7 points or above in 2022 is higher than that in year 2017. (The report must include the (i) null hypothesis and alternative hypothesis, (ii) rejection…

account_circle   Math StatisticsQ&A LibraryPolokwane Butchery supplies Vienna sausages in the entire of KZN province. An Inspector from the CCSA has been sceptical of the mass of the Vienna sausage packs after receiving numerous complaints. He wants to investigate the marked mass shown on Vienna sausages. A pilot study showed a mean of 11.8kg per pack and a variance of 0.49kg. How many packs should the Inspector sample in order to be 99% confident that the sample mean will differ by at most 0.2kg? Polokwane Butchery supplies Vienna sausages in the entire of KZN province. An Inspector from the CCSA has been sceptical of the mass of the Vienna sausage packs after receiving numerous complaints. He wants to investigate the marked mass shown on Vienna sausages. A pilot study showed a mean of 11.8kg per pack and a variance of 0.49kg. How many packs should the Inspector sample in order to be 99% confident that the sample mean will differ by at most 0.2kg?…