BT thống kê khoa học ra quyết định trong kinh doanh số (10)

Individual Exercise DECISION SCIENCE AND STATISTICS FOR MANAGER – MKTG BUAD 555 Full name: Le Thi Thu Hien Classes: GaMBA01.N03 Question 1: A.Answer (Đ), error (S) for the following sentence and explain why? 1.Statistical indicators reflecting the characteristics of the unit overall (Đ) Because statistical indicators reflecting the overall conditions in the overall time and location specific And targets that reflect common relationships and characteristics of large numbers of units or all units overall Cumulative frequency distribution of frequencies in the table denoted by the absolute number (Đ) Since the overall distribution of a certain number of criteria, the overall unit is distributed in the Organization and we will have a statistical distribution according to the criteria and Duo performing a frequency distribution table number and frequency of accumulation Cumulative frequency (denoted Si) indicates the number of processing units larger or smaller than a specific amount of processing and is the basis for determining a unit stand in any position in the sequence number is How much weight variable Cumulative frequency (denoted Si) indicates the number of processing units larger or smaller than a specific amount of processing and is the basis for determining a unit stand in any position in the sequence number is How much weight variable Cumulative frequency of a value xi is the total frequency of values of frequency values smaller than xi Therefore, cumulative frequency expressed in absolute numbers Coefficient of variation allows comparison of variability of the criteria of the two studies different types of phenomena (Đ) Coefficient of variation is expressed by relatively few, it can be used to compare the different criteria, such as the coefficient of variation compared to labor productivity with some variation on salary, variable coefficients of wages with natural variability of the rate of completion of the production Meanwhile, other norms such as the variability between, the average absolute deviation, deviation target unit calculations are similar to the calculation of the target unit of research, should not be used to compare the different criteria Approximately reliable for the average of overall proportional to the variance of the overall (Đ) Because of these factors affect the magnitude is about reliability of the overall variance Overall as equally (as small variance), between estimates as small So, about the value of reliable high an overall average proportional to the variance of the overall Regression coefficient (b 1) reflects the dimension and extent of the influence of criteria cause results to criteria (Đ) Because: The model of the overall linear model: ˆ Where: b i = b + b X i I = b + b X i is the coefficient of Y block is used to estimate β b is the slope (regression coefficient) used to estimate β Regression coefficient of influence of x (number of criteria of reason) for y (value of the criteria results, in particular when x increases one unit, the average increase b1 * y units B Choose the plan that best answer (the plan is properly applied red) 1) The difference between the scale and scale rate of about is: a) Units b) core origin absolutely no c) The application of arithmetic to calculate d) Both a) b) and c) 2) Speaking of which below is not correct one: a) an equalized or compensated the difference between the amount of processing b) An amount affected by unexpected changes c) Each sequence of only one example d) Both a) b) and c) 3) The method of expression tend to develop basic phenomena in order to: a) Arrange in order of sequence number increases (or decreases) gradually b) Ensure the quality comparable to the levels in the sequence number c) Eliminate the impact of random factors d) No of the above 4) the column chart (histograms) is characterized by: a) Between the column spacing b) width of the column width of each expression of c) Chiều cao cột biểu thị tần số c Height of the column indicated frequency d) Both a) and b) are correct e) Both b) and c) are correct f) Both a), b) and c) are correct 5) Measures to limit sampling error: a) Increase the number of units overall sample b) Using appropriate sampling method c) To reduce the variance of overall d) Both a), c) e) Both a), b) f) Both a), b), c) Question (1.5 e) A business to an estimated average hours per worker to complete how much product to put norms Director factory to build around an estimated error in a product and reliability of 95%, experience his standard deviation of productivity in a product is Find the number of workers should be investigated to set norms Suppose the selected samples (with sample sizes calculated above) the average number of products which they completed in 35 hours with a standard deviation of 6.5 Please estimate the average productivity per hour of all of workers with 95% reliability reliability α = / 2% = 2.5% is 1960 Therefore, some workers need to be investigated is 138 people (n = 138) So in an average yield is: Questions (1.5 e) There are two methods used for teaching two classes of students the same object To see the impact of teaching methods to the study results are not different, people selected randomly from each class some students to check their learning outcomes Number of students selected in the first class is a group (20 students) with a grade point average is 8.1 points and standard deviation of 0.7 points Number of students selected in second class group (25 students) with a grade point average of 7.8 points and standard deviation of 0.6 points 0.05 significance level to draw your conclusions Call method for teaching a class effect of and are effective methods of teaching second grade Pair hypothesis verification is H : H 0: : No difference H : H 1: : There are differences Verification: Instead of: we have: s = 0.646097408, d = 1.547754236 Investigation table t α / 2, 43 = (2,018 +2,015) / = 2.0165, thus | t |