be drawn from normally distributed populations. • These populations should have equal variances. • The measurement scales should be at least interval so that arithmetic operations can be used with them. Parametric tests place different emphasis on the importance of assumptions. Some tests are quite robust and hold up well despite violations. For others‚ a departure from linearity or equality of variance may threaten the validity of the results. Assessing the consequences of violating a statistical
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outperform the original portfolios and therefore it seems as though the optimisation do not improve the return of the portfolios. This might be due to the uncertainty of the expected returns used in this thesis. Keywords: Efficient frontier‚ mean-variance optimisation‚ portfolio optimisation‚ Sharpe ratio 1 Table of contents 1 INTRODUCTION 3 1.1 BACKGROUND ......................................................................................................................................
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|0 |1 |2 |3 |4 |5 |6 | |# of policies |21 |15 |5 |4 |2 |3 |2 | • Find the mean number of claims per day. • Find the sample variance and standard deviation. 4. A survey carried out for a supermarket classified customers according to whether their visits to the store are frequent or infrequent and
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08 ETHE AUSTRALIAN NATIONAL UNIVERSITY SCHOOL OF FINANCE AND APPLIED STATISTICS First Semester Examination 2010 QUANTITATIVE RESEARCH METHODS (STAT1008) Writing Period: 3 hours duration Study Period: 15 minutes duration Permitted Material: Non-programmable calculator‚ dictionary and 1 A4 page with notes on both sides Instructions to Candidates: • Attempt ALL questions. • Each question is of equal mark value. • Start your solution to each question on a new page. • To ensure full marks
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interpret the coefficient of correlation r=0.853=0.9236 (There is strong correlation between two variables as its near 1) d) the coefficient of determination r2=0.853(The magnitude of the coefficient of determination indicates the proportion of variance in one variable‚ explained from knowledge of the second variable) e) the standard error of estimate S.E=0.3133(The standard error is the estimated standard deviation of a statistic) f) Conduct a test of hypothesis to determine whether the
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Descriptive Statistics Mean Variance Standard Deviation Sample Covariance If it is greater than zero‚ upward sloping. This is scale dependent. Sample Correlation This is scale independent: between -1 and 1‚ close to 1 is upward‚ 0 is central‚ -1 is downward sloping. Finding the regression Regression formula with one regressor Slope Intercept Finding R2 TSS=ESS+SSR The Coefficient of Determination = R2 This gives the total fit of ‚ between 0 (chance) and
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executive salary for the following groups of industries: I. Industrial and Basic Materials II. Industrial and Technology III. Basic Materials and Technology Before conducting the test above‚ perform a test on equivalent population variances for each pair of company type. In a brief paragraph‚ comment of the conclusions of the test results. d. Determine the upper and lower range salary values for each industry at 90% and 95% confidence intervals e. Perform a test of normality
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transmission. (2 marks) 4. Consider a random variable M with the probabilities specified in the following figure: k 3 6 9 12 15 P (M = k) (i) Find E (M). (2 marks) (ii) Find E (M2). (2 marks) (iii) Find the variance of the random variable M. (2 marks) (iv) Find the standard deviation of the random variable M. (2 marks) 5. 1200 employees were surveyed about their meals preference in the cafeteria. The following information was obtained:
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Mathematics Department Tutorial Sheet No. 3 MAL250(Probability and Stochastic Processes) 1. The percentage of alcohol (100X ) in a certain compound may be considered as a random variable‚ where X (0 < X < 1) has pdf fX (x) = 20x3 (1 − x)‚ 0 < x < 1. Suppose that the selling price of the above compound depends on the alcohol contents. Specifically‚ if 1/3 < X < 2/3‚ the compound sells for c1 dollars/gallon otherwise it sells for c2 dollars/gallon. If the cost is c3 dollars/gallon‚ find the probability
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Introduction to Management Science‚ 10e (Taylor) Chapter 11 Probability and Statistics 1) Deterministic techniques assume that no uncertainty exists in model parameters. Answer: TRUE Diff: 1 Page Ref: 489 Main Heading: Types of Probability Key words: deterministic techniques 2) Probabilistic techniques assume that no uncertainty exists in model parameters. Answer: FALSE Diff: 1 Page Ref: 489 Main Heading: Types of Probability Key words: probabilistic techniques 3) Objective
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