which one of the following symbols could represent a population parameter?
which of the following statements about probability is wrong?
to know the average level of lung capacity of grade 2015 students at the sun yat-sen university, an investigator measured the lung capacity of students in 30 sampled classes of grade 2015 from this university. the whole collection of the measured lung capacity data is a .
a statistic is
to make a statistical inference for the population from a sample, the sample should be:
the statistic in statistics is:
the conversion of variables can only be done from quantitative variables → nominal variables → ordinal variables →binary variables, which cannot be converted in an opposite direction.
the unit of the coefficient of variation is the same as the unit of the original variable.
which of the following conditions could make the binomial distribution b(n, π) approximate the poisson distribution?
which of the following statements about the probability is wrong?
whenλ is large enough, poisson distribution tends to be a normal distribution.
for data subject to a normal distribution, the probability of a variable between 1.96 and 1.96 is 0.95.
please list the main differences among poisson distribution，binomial distribution and normal distribution?
please list the main difference between reference range and confidence interval?
if a t-test shows the difference between two sample means is statistically significant (p<0.05), then confidence interval of the difference between the two population means may not be
which of the following statements correctly explains the meaning of the interval .
which of the following formulas can be used to estimate the 95% confidence interval for the population mean of a normal distribution_____
for a group of given data, the relationship between 95% ci and 99% ci is that
when we intend to estimate the sample size for confidence interval of a population mean which follows a normal distribution, which of the following condition requires a larger sample size while other background remains the same? _____
how do we distinguish the standard error and the standard deviation?
in hypothesis testing of two groups, which of the following is a null hypothesis?
which of the following is not a step of hypothesis testing?
which one of the following statements about p is correct?
when comparing the effect of two drugs, under which situation one-side test can be used?
which of the following is not a precondition of two independent sample t test?
which of the following is not a necessary pre-conditions of the analysis of variance (anova)?
the term ‘variance’ of the method ‘analysis of variance’ means: .
which of the following methods cannot be used to compare means?
which of the following tests is not a non-parametric test?
in comparing effective rates between two groups, what are the possible factors that may influence the power for hypothesis testing?
when , which one of the following statements is correct?
in linear regression ysis, the larger the is, the better the regression model will fit.
what is the difference between experimental group and control group?
the best control method for confounding bias is _________.
in the case-control study of obesity and hypertension, the cases were from patients found by medical examination in a hospital, and the control was an employee of an enterprise located in the hospital. the design may exist .
inappropriate sampling methods may result in samples that do not represent the population well.
using statistical tables and charts must be more clearly than text.
make sure the statistical tables and charts can stand alone from the text.
values to be compared should be placed side-by-side.
to know the average level of lung capacity of students at a university, an investigator measured lung capacity of 500 students randomly sampled from the university. the whole collection of measured lung capacity is a .
the term “population” in statistics is defined as _________.
which of the following is not a qualitative variable: ______.
in the research based on sampling, when sample size is larger, _________.
if statistical inference is to be made through the sample, the sample should be_____
if a t-test shows the difference between two sample means is statistically significant, then the aller the p value is
standard error is used to reflect the variation of: .
analysis of variance (anova) is a test for the difference in .
which of the following is not a precondition for analysis of variance: .
in anova for the completely randomized design, there must be:
270 people with diabetes are randomly ided into three groups and treated with a, b and c methods, respectively. the difference of blood glucose before and after taking the medicine is taken as the effect. to compare the effects of the three methods, which one the following statements is correct:
which of the following statement about test of contingency table is correct?
which of the following statements about the probability is wrong?
when we use rank sum test to compare two samples:______.
which one of the following is not appropriate for describing the linear correlation coefficient?
there are two pairs of random variables (x1 and y1, and x1 and y2) which following a bi-variable normal distribution respectively. linear regression yses are conducted based the two pairs of variables. the results show that b1=0.83 (p=0.015) and b2=0.65 (p=0.005). which of the following statement is correct?
in simple linear regression ysis, ssresidual indicates _________.
comparing the prevalence rate of several diseases in a certain place over two years, the most suitable statistical graph is_________.
which of the following does not belong to the purpose of the histogram or frequency distribution table?
probability is the measure of the likelihood that an event will occur.
for a poisson distribution, the mean is equal to the variance.
so-called “95% confidence interval for population mean” is applied to estimate the location of population mean, with a confidence level 95%.
for the hypothesis test whether the population correlation coefficient is 0, the aller the p value, the closer the relationship between the two variables.
in two sets of data, two variables with a larger regression coefficient b are more closely related than variables in the other dataset.
the soft palate is also called __________
the back of the tongue helps to produce __________ sounds.
/p/, /b/, /m/ and /w/ are produced with the help of __________.
the sounds produced with the help of the upper teeth are called __________ sounds.
the study of speech organs is important to know the nature of __________.
the organs that take part in production of speech sounds are called __________
the positional variants of the same phoneme are known as __________.
in english, [l] and [ɫ] are allophones of the phoneme /l/ because they occur in ___________________, i.e., they never appear in the same sound contexts. [l] always occurs before vowels (as in the word leaf, look), while [ɫ] comes after vowels and before consonants (as in the word feel, cold).
using the diacritics provided by the ipa, _____________ transcription captures as many aspects of a specific pronunciation as possible and makes very subtle distinctions between sounds.
/p/ and /b/ can appear in initial position (as in pin and bin) and also in final position (as in rope and robe)．they are in phonemic contrast and said to form a _______________ because they occur in the same environment and distinguish meaning.
like all languages in the world, english phonemes are also ided into vowels and consonants. the distinction between the two lies in the obstruction of __________.
the __________ pronunciation, or rp for short, is the instantly recognisable accent often described as ‘typically british’. it is defined in the concise oxford english dictionary as “the standard accent of english as spoken in the south of england”.
the vowel __________ can be described as low, front, and unrounded, but the feature “unrounded” is usually omitted because all front vowels in english are unrounded.
syllabically, although a diphthong is a combination of two vowel sounds, and the tongue glides in the production of it, it is perceived as one phoneme, not two. thus, diphthongs are treated as having one __________ only.
words such as fire /faɪə/, flour /flaʊə/, or loyal /lɔɪəl/ are considered by the native english speakers to have only one syllable, whereas higher /haɪə/ and player /pleɪə/ are more likely to be heard with disyllabic realizations because the third vowel is a __________.
in the production of a consonant sound, the air stream from the lungs meets no obstruction of any kind in the throat, the nose, or the mouth, while in the pronunciation of a vowel, the air stream from the lungs is obstructed in one way or another.
daniel jones worked out a set of cardinal vowels that students learning phonetics could be taught to produce, the aim of which is to give an approximate picture of the degree and direction of the tongue movement involved.
/i:/ and /ɪ/ are both high front vowels, but /i:/ is a bit lower and more forward than /ɪ/. in addition, /i:/ is tense in that the root of the tongue is more advanced than with /ɪ/, which is lax.
english diphthongs are ided into both falling diphthongs (the first vowel sound is pronounced longer, louder and stronger than the second one), and rising diphthongs (the second sound is produced longer and stronger than the first
if two adjacent vowel sounds occur in different syllables — for example, in the english word re-elect (/ˌri:ˈɪlekt/) — the result is described as hiatus not as a diphthong.
consonants are formed by interrupting, narrowing or erting the airflow in a variety of ways. there are three ways of classifying the english consonant sounds: __________ of articulation, manner of articulation and voicing.
when the letter n come before g or k, it is pronounced as /ŋ/ as in strong, bang, thank, drink. however, when g is followed by e or i, the letter n is read as /n/ as in strange, stranger, arrange, longitude because the letter g is pronounced as __________.
rp has two allophonic variants of /r/. one is retroflex [r], and the other is tapor flap [ɾ]. in the pronunciation of retroflex [r], the tongue curls backward and retroflexes at the __________.
the /r/ may be replaced by an alveolar tap [ɾ] in intervocalic positions (e.g. very, sorry, tomorrow) and in word-final /r/ __________ with an initial vowel (e.g. far away).
generally speaking, plosive sounds undergo three stages: the closing stage, the compression stage and the __________ stage.
the manner of articulation refers to the way in which the airstream is obstructed. for example, with plosive sounds, the articulation acts in such a way that the air is temporarily trapped, and then suddenly released.
generally speaking, the place and the manner of articulation are the two common features of any languages except the voicing, which is language specific. for example, voicing is a distinctive feature of mandarin chinese, whereas aspiration is the distinctive feature of english.
plosives occur when the airstream is blocked or stopped completely before its release. they are also known as stops because they involve the complete blockage of the airstream.
the sound /ŋ/ remains unchanged at the word boundaries where it is followed by a word beginning with a vowel sound as in bring it (/brɪŋɪt/) and sing us a song (/sɪŋəs ə sɒŋ/). however, in the case of adjectives, the adding of the suffixes –eror -est to the comparative and superlative degree of the words longer and longest has changed the pronunciation of /ŋ/ into /ŋɡ/.
within the class of approximants, lateral /l/ and retroflex /r/ are further distinguished from semi-vowels /j/ and /w/. this is because /j/ and /w/ are made without a restriction to the airflow. they are phonetically like consonants but phonologically like vowels.
the general distribution of rp consonants is that all consonants can occur at the initial position as singletons except /n/, and that all consonants can appear at the final position as singletons except /h, w, j, r/.
the dark [ɫ] has two types of distributions. one is in word-final position, after vowel, as in call and real, and also after vowel, before consonant, such as cold and help. the other is syllabic [ɫ̩]: e.g. little and table.
both ‘clear’ [l] and ‘dark’ [ɫ] are formed with the tip of the tongue touching the teeth ridge. the only difference is that in the articulation of the ‘clear’ [l], the back part of the tongue is raised towards the hard palate. in the articulation of the ‘dark’ [ɫ], the front part of the tongue is raised towards the soft palate and slightly velarised, with a concave upper surface.
within the class of approximants, lateral /l/ and retroflex /r/ are further distinguished from semi-vowels /j/ and /w/. this is because /j/ and /w/ are made without a restriction to the airflow. they are phonetically like consonants but phonologically like vowels.
affricates occur when a complete closure is made somewhere in the mouth, and the soft palate is raised. air pressure increases behind the closure, and is then released more slowly than in plosives.
the sound /ŋ/ remains unchanged at the word boundaries where it is followed by a word beginning with a vowel sound as in bring it (/brɪŋɪt/) and sing us a song (/sɪŋəs ə sɒŋ/). however, in the case of adjectives, the adding of the suffixes –eror -est to the comparative and superlative degree of the words longer and longest has changed the pronunciation of /ŋ/ into /ŋɡ/.
inaudible (incomplete) release of plosives refers to the process of articulation of a plosive is not complete. it has only two stages, namely, the closure and the compression, without the release.
generally speaking, the place and the manner of articulation are the two common features of any languages except the voicing, which is language specific. for example, voicing is a distinctive feature of mandarin chinese, whereas aspiration is the distinctive feature of english.
english diphthongs are ided into both falling diphthongs (the first vowel sound is pronounced longer, louder and stronger than the second one), and rising diphthongs (the second sound is produced longer and stronger than the first
if two adjacent vowel sounds occur in different syllables — for example, in the english word re-elect (/ˌri:ˈɪlekt/) — the result is described as hiatus not as a diphthong.
stressed syllables bear four physiological properties: loudness, vowel duration, pitch and vowel __________.
in fact, the formation of syllabic consonants has much to do with the __________ principle, a term in auditory phonetics for the overall loudness of a sound relative to others of the same pitch, stress and duration.
in english, [l] and [ɫ] are allophones of the phoneme /l/ because they occur in ___________________, i.e., they never appear in the same sound contexts. [l] always occurs before vowels (as in the word leaf, look), while [ɫ] comes after vowels and before consonants (as in the word feel, cold).
the __________ pronunciation, or rp for short, is the instantly recognisable accent often described as ‘typically british’. it is defined in the concise oxford english dictionary as “the standard accent of english as spoken in the south of england”.
stress is being used in a more general way. it refers to the syllable that receives lexical stress. __________, on the other hand, is being used in a more specific way. it is a place where a tonal marker will fall on the lexically stressed syllable.
in more than three-syllable words, if the primary stress falls on the third syllable or later, the secondary stress are usually marked on one of the preceding syllables, for example, introduction / /ɪntrədʌkʃn/ and education /eʤukeɪʃn/.
word stress in english is not as predictable as it is in other languages, and therefore, the stress placement in english words is not rule-governe
phonological treatments of syllable structure usually call the first part of a syllable the onset, the middle part the nucleus and the end part the cod the combination of nucleus and coda is called the rhyme.
not all english vowel phonemes can occur in the cv syllable pattern, but all can appear in the cvc pattern.
in coda position, the maximum number of clusters is four. many clusters of two or three and virtually all cluster of four are the result of adding a plural /s, z/ or a past tense /t, d/ inflection to a stem ending in two or three consonants
the soft palate is also called __________.
/p/, /b/, /m/ and /w/ are produced with the help of __________.
the study of speech organs is important to know the nature of __________.
the positional variants of the same phoneme are known as __________.
using the diacritics provided by the ipa, _____________ transcription captures as many aspects of a specific pronunciation as possible and makes very subtle distinctions between sounds.
like all languages in the world, english phonemes are also ided into vowels and consonants. the distinction between the two lies in the obstruction of __________.
the __________ pronunciation, or rp for short, is the instantly recognisable accent often described as ‘typically british’. it is defined in the concise oxford english dictionary as “the standard accent of english as spoken in the south of england”.
the vowel __________ can be described as low, front, and unrounded, but the feature “unrounded” is usually omitted because all front vowels in english are unrounded.
syllabically, although a diphthong is a combination of two vowel sounds, and the tongue glides in the production of it, it is perceived as one phoneme, not two. thus, diphthongs are treated as having one __________ only.
the duration of a diphthong is similar to that of a __________ vowel.
consonants are formed by interrupting, narrowing or erting the airflow in a variety of ways. there are three ways of classifying the english consonant sounds: __________ of articulation, manner of articulation and voicing.
when we discuss the english consonant, we begin with voicing first, then the place of articulation and lastly, the manner of articulation. the sound __________, for instance, is said briefly as voiceless palate-alveolar affricate.
__________ release refers to the air used to produce the stop is released through the nose rather than the mouth, namely, the velum is lowered before the stop closure is removed and the air pressure will be released through the nose instead of the mouth.
fricative sounds can be maintained as long as there is air in the lungs; for this reason they are known as __________.
rp has two allophonic variants of /r/. one is retroflex [r], and the other is tap or flap [ɾ]. in the pronunciation of retroflex [r], the tongue curls backward and retroflexes at the __________.
the minimum unit of speech is a syllable. syllables have a minimum of one (as in the word air /eə/), and a maximum of __________ structural parts (as in the word text /tekst/).
__________ consonants are consonants which form the nucleus of a syllable that does not contain a vowel.
the v and cv syllables are referred to as a/an __________ syllable because they end with a vowel.
with __________ clusters of three consonants, the first sound is always /s/, the second sound is a voiceless plosive /p, t, k/, and the third sound is one of the four approximants /l, r, w, j/.
there are cases where a consonant or a cluster could be either the coda to the first syllable of a word, or the onset to the second, we can say that it fulfils both functions, for instance, the /b/ in rabbit, the /st / in posting, the /n/ and /m/ in cinema. this is known as ___________.
in the production of a consonant sound, the air stream from the lungs meets no obstruction of any kind in the throat, the nose, or the mouth, while in the pronunciation of a vowel, the air stream from the lungs is obstructed in one way or another.
daniel jones worked out a set of cardinal vowels that students learning phonetics could be taught to produce, the aim of which is to give an approximate picture of the degree and direction of the tongue movement involved.
tongue position indicates whether the front (as for /i:, ɪ, e, æ/), the central (as for /ɜ:, ə, ʌ/) or the back (as for /ɑ:, ɒ, ɔ:, ʊ, u:/) of the tongue is involved according to the horizontal movement of the tongue.
vowel /æ/ is distributed in syllable-initial, medial and final position (e.g. act /ækt/, hat /hæt/ and rapid /ræpɪd/, but not in word-final position.
english diphthongs are ided into both falling diphthongs (the first vowel sound is pronounced longer, louder and stronger than the second one), and rising diphthongs (the second sound is produced longer and stronger than the first).
the manner of articulation refers to the way in which the airstream is obstructed. for example, with plosive sounds, the articulation acts in such a way that the air is temporarily trapped, and then suddenly released.
plosives occur when the airstream is blocked or stopped completely before its release. they are also known as stops because they involve the complete blockage of the airstream.
the sound /ŋ/ remains unchanged at the word boundaries where it is followed by a word beginning with a vowel sound as in bring it (/brɪŋɪt/) and sing us a song (/sɪŋ əs ə sɒŋ/). however, in the case of adjectives, the adding of the suffixes –er or -est to the comparative and superlative degree of the words longer and longest has changed the pronunciation of /ŋ/ into /ŋɡ/.
within the class of approximants, lateral /l/ and retroflex /r/ are further distinguished from semi-vowels /j/ and /w/. this is because /j/ and /w/ are made without a restriction to the airflow. they are phonetically like consonants but phonologically like vowels.
the dark [ɫ] has two types of distributions. one is in word-final position, after vowel, as in call and real, and also after vowel, before consonant, such as cold and help. the other is syllabic [ɫ̩]: e.g. little and table.
syllables are units of language, aller than a word but larger than a phoneme, and every language is said to have syllables.
the english words consist of at least one syllable, and many words have two, three, four, or more syllables, and so do the chinese words.
phonological treatments of syllable structure usually call the first part of a syllable the onset, the middle part the nucleus and the end part the coda. the combination of nucleus and coda is called the rhyme.
a syllable may have one onset consonant, as /s/ in sit, tow onset consonants as /sp/ in spit, three onset consonants, as /spr/ in spring, or no onset consonants as in it /ɪt/.
in english, syllabic consonants occur when /l, n/ or /m, ŋ/ (standing as the peak of the syllable instead of the vowel) follows a homorganic (i.e., the same place of articulation) plosive (or occasionally a fricative).
a syllabic consonant is to be interpreted phonologically as /ə/ plus a consonant, but phonetically as the under-stroke [ ˌ ] combining vertical line below a consonant. thus, the word button is phonologically ['bʌtn̩] but phonetically /'bʌtən/.
not all english vowel phonemes can occur in the cv syllable pattern, but all can appear in the cvc pattern.
chinese has predominantly open syllables with only nasals /n/ and /ŋ/ permitted in syllable-final position. therefore english is a cv language, while chinese is a cvc language.
english has a complex system of consonant clusters, in which two or more consonants occur in sequence in onset or coda position.
in coda position, the maximum number of clusters is four. many clusters of two or three and virtually all cluster of four are the result of adding a plural /s, z/ or a past tense /t, d/ inflection to a stem ending in two or three consonants