MIGRATION AND THE CANADIAN URBAN SYSTEM: PART II, … · The migration data were obtained directly...
Transcript of MIGRATION AND THE CANADIAN URBAN SYSTEM: PART II, … · The migration data were obtained directly...
MIGRATION AND THE CANADIAN URBAN SYSTEM:
PART II, SIMPLE RELATIONSHIPS
J.W. Simmons
Research Paper No. 98
Centre for Urban and Community Studies
University of Toronto
July 1978
ABSTRACT
This paper develops a series of simple regression models to
explain the patterns of migration rates and flows which were described
in research paper No. 85. In brief the exercise was only partly
successful, with large amounts of unexplained variation remaining.
Demographic, social and envirorunental variables appear to be at least
significant economic measures in determining population growth.
Introduction
Migration Rates
Migration Flows
Migration and Growth
Conclusions
References
CONTENTS
- Review
- The Census Data and Methods of Analysis
- Out-Migration
- In-Migration
- Other Mobility Rates
- The Flow Matrix
- The Allocation Model
- Net Migration
- Immigration
- Natural Increase
- Net Migration
- Path Models of Population Growth
Appendix Independent Variables
LIST OF ILLUSTRATIONS AND TABLES
ILLUSTRATIONS page
1 The Canadian Urban Sys tern ..••...•...•...•••.•.•...••............ 3
2 Age Distribution of Intermunicipal Migrants ..•...••....•....... 16
3 Fluctuation in Wage and Employment Indices ...•...•...•••.....•. 18
4 Annual Variations in Growth Components .••••.••••...•.•••....•.. 52
5 Path Analysis: Population Growth ....••.....•••...•..••.....•.• 62
6 Alternative Specifications of the Growth Model ............•.•.• 64
TABLES
1 L.ist of Urban Regions .•.•...•....••............•..•.........•... 4
2 Measures of Mobility •...•.......•....••.••....••..•....••...••.. 8
3 Correlations among Mobility Rates .....•....•..•..•••...•......• 10
4 The Correlates of Out-Migration Rates ....••..•••.•..•.•.•..•.•• 19
5 Out-Migration: Selected Regression Models .•......•.....•...•... 22
6 The Correlates of In-Migration .•••.......•.....•.•............. 25
7 In-Migration: Regression Models ....•••.••.....................• 2 7
8 Regression Models: Net and Gross Migration •..•....••..•..•...•. 30
9 Correlates of Migration Flow Measures •......................... 37
10 Regression Models: Migration Flow Matrix .•....•...........•.•.. 28
11 The Correlates of Migration Flow Ratios ...•...............•.... 42
12 Regress ion Models: Allocation .........•.........•........•...• 42
13 The Dimensions of Social Variations in Canada ..•....••.......•. 45
14 The Correlates of Net Migration Flows .••.•......••.•.•....•..•. 48
15 Regression Models: Net Migration Flows .•...•................••. 49
16 The Components of Population Growth, by Hierarchical Order in the Urban Sys tern by Region ................................ 53
17 The Correlates of Net Immigration and Natural Increase Rates ... 55
18 Regression Models: Immigration and Natural Increase .•.•.•..••• 59
Tables continued:
A 1 Independent Variables: Measures obtained from 1971 Census
2 Other Independent Variables
3 Access Measures
4 Variables Used in the Analysis of Flow Matrices
PREFACE
This research paper continue3 the discussion and analysis of
the 1966-1971 Canadian migration patterns begun in Research Paper
No. 85 in this series. That paper was entirely descriptive, whereas
this study links the patterns of migration to the social and economic
characteristics of urban regions as described in the 1971 Census.
Hypotheses linking migration flows to city size, distance, and differ
entials in income and employment are examined for the 124 urban-centred
regions which comprise the Canadian urban system.
I would like to acknowledge the support of the Centre for Urban
and Community Studies and the Department of Geography in preparing the
paper. Siegfried Schulte gave me invaluable technical advice. Jane
Davies created the figures and Bev Thompson typed the manuscript.
Larry Bourne and Neil Field provided useful suggestions.
This project was funded by a research grant from Canada Council.
JWS
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MIGRATION AND THE CANADIAN URBAN SYSTEM: PART II, SIMPLE RELATIONSHIPS
INTRODUCTION
Since the work of Ravenstein (1885, 1889) in the nineteenth century,
researchers have sought order in the patterns of migration among places
and regions. Why do people migrate in the first place? How do they
choose among alternative locations? And, increasingly, how does this
migration contribute to differential rates of population growth and capi-
tal investment? This paper explores some of the causal factors put forth
in the literature over the years to explain migration patterns, as they
apply to the Canadian urban system. The descriptions of migration rates,
flows of migrants, and net transfers among the urban regions of Canada,
for the same period, 1966-1971, have already been set forth in an earlier
paper (Simmons, 1977). In the present paper a number of simple regression
models are constructed to link migration patterns to various urban char-
acteristics as defined in the 1971 Census.
The rest of this section briefly reviews the data and units of
analysis used in the study. The second section focusses on the various
definitions of migration rates: including in, out, gross and net migration
as well as migration efficiency. Each of these measures can be related to
various characteristics of the 124 urban regions themselves, such as size,
isolation, economic base and demographic structures. The third section
looks at a more complex problem, the pattern of movements among the over
15,000 (124 x 124) pairings of urban regions in the Canadian urban system.
The final section pulls together the results of the previous analyses and
discusses their implications for understanding change in the urban system.
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Review
The description of migration in the Canadian urban system presented
in Sinnnons (1977) was built upon a series of hypotheses about the spatial
organization of the urban system, which were then applied to a particular
data set from the 1971 Census. The spatial units of analysis are extended
urban regions, consisting of one or more counties or census divisions
centred on an urban node, such as a city, urbanized area or census metro-
politan area. The 260 census divisions of Canada were then allocated to
124 extended urban regions (Figure 1). 1 Given the set of urban areas
(Table 1), the definition of the urban system was completed by assigning
each urban area to one of five levels in an urban hierarchy, and linking
each urban region to a single high order centre. The result is a simple
urban hierarchy, consisting of two 5th order sub-systems (Toronto, Montreal)
eleven 4th order sub-systems (i.e. Vancouver, Winnipeg) and so on, per-
mitting us to examine systematic differences in migration characteristics
by both city size and membership in a regional subsystem.
The migration data were obtained from a sample of one in three house-
holds in the 1971 Census. Respondents were asked whether they had lived
1The migration data were obtained directly from Statistics Canada, but other census measures on income, ethnicity, etc., were obtained through the Institute for Behavioural Research (I.B.R.) at York University. Statistics Canada did not generate a summary tape for census divisions, nor did I.B.R., but the latter were able to provide a tape using enumeration areas which could be aggregated. For some reason, however, I.B.R. excluded the Territories from their master tape. Statistics Canada, for their part, have horribly intermingled the published data for the Yukon and Northwest Territories for many variables, and it was difficult to obtain a consistent set of measures for these units. Nonetheless measures for urban regions centred on Whitehorse and Yellowknife have been obtained and inserted into the data file manually.
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e
i ~--.,,_ ....._ ........_,.._., II
I I
I I
/ I
/
J. 2. 3. I,.
5. 6.
Corner:r.rool CranJ ;·;, 11.;
St. Joh;1'~-
7. A;.-,1-,erst 8. Truro 9. Ne·,.: G 1 a,:;:::•\·:
l 0. Sydney 11. Yar1;1out~1
12 . fad if [l}: 13. l:cn tvi 11 l.
14. Bathurs~ 15. Cat:Jj' be J l l C»l
] (,. Fdr:1rn1dP tcT<
] 7. ])redr~• ri~ C' t
18. }h · n c tc;:1
19. ~~f'r,,.;·c:ist1t-2 0 . s t . ,k ! l1 )
21. Chi cc.:; l i:::i 22. Bai(' Ccr:c;_:l1
23. NGU!'.H.:
21;. R.i ;•1cit:s Li 25. Eiv:i L•l<• (it; Lo.c;' 26 _ Ec1 :_iyn
27. \"~11 d'CJ1· 2L~ Dru~:1:non-.~y~f 11-.' 29. Th<tford ~ljnc~:
3 0 ~ c~"'i\~' ,] n s \~ i 11 L'.
3]. \'aJL:dicld 12. ML111trc.:l 33. Quc1:cc 34, St. Jc;:1-. 35. St. Jero':h.: 3G. St. lly;-icinthc 37. Sorf!1 3g. Lachut~·
40. Hull 41 . M :·,; ·o g l; 7 . S Ii c· r b r cK· !. ' · 43. Grnnby
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TABLE 1
LIST OF URBAN REGIONS
I, !., .. J ti J i t: L ~ 1
l,5. Trojs I:"iYi~~-cs
11(. }1onl L;!·Jr"it:r
t; 7 . ~-: L " G (' ( l ~~I :_~
4f'.. l1.1ic1: :l "f"L;,·;; 49. VicLori~villc
50. Ot Ur""'· 51. Corm-•:.1J 52. Hroc..kvlll.C' SJ. l'._,11bro!:' 54. H3v:l;u;l,1:ry 55. Kinge::tc;, .56. Pcterh1.Jrc·uyh 57. Lindsay 58. F~ell.::·.;ilJ.:
)9. Cohou~· t;
60. NortL 6L K:i rl·.1.->r:J L"h" 62. Ti8';1ins 63. Sudbl:ry 64. Sa~lt SLe. ~ari1 (,5. Barri c· 66. Osl-.a«.'a 67. Toronto 6 8. Owen Sc•un d 69. Wine.is.Jr 7 0. Chat l.c 71. Sarnia 72. St' ThC•i:i.'.i".
7 3. Lo::.C: on 71.*. StratforJ 7 S. Ri tcho:1c:;~
71. Orn:n:·(\·; lle 78. Goderich 79. Guel;·h 80. Simcoe 81. Brantford 82. St. C;•t L1rirics 83. Woodsto }: 84. Thunder B;iy 85. Ke;10 r u
86. Dauphin 87. Bra:1dr'n
t8. f;C;
90. 91. 92.
J'rin•" A]br; t
>:er-LL B:1ttlt,fJ1-;~
E\,;·j f ,_ Curr·~~l! t
}~()·~~ ( j ,-:\·-
95. Sc::,c ~· atc•on
96. Rq;i n2
97. Esllvan 9.S. \·:c-yb'...1rn
99. LctL:.,ri cg·.::: JOO. Hc.:dicir,c lict 101. :Re:d Deer 102. Gr ii:. de· Pr ai ri c 103. Cdf;::lry i 0:1.. Er~r .. :::~ 0:1
l OS. Pt. Alber:· 'i JOC. !';;:;n::i1~,·:::
107. Pc;;tjctc~ 108. K~ir'Jtiups
109. Vc:;~non
llO. Tr;:;il 111. Cnrnbrook 112. Kclowna 113~ '\'~ct_oria
114. Vauccuvcr 115. l~cJ.son
116. Pr i nee Ge~~ r;:,« 117. Di·h·son Creek llE. I'r:Lr~cc Ru;:H::rt 11 9 . \.' i1 l i n::1 <; Lah· 120. Courtenay 121. Ch:i lliwack J 22. J'O\.:cll ki ver 123. \·,'h·: tchorsc 12l. Y~llo~knifc.
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in a different house, municipality, or county five years earlier, and
if so, where. The movers among the extended urban regions defined here
include 11.3 per cent of the population, five years of age and older;
in-movers from abroad amount to an additional 4.2 per cent. Approximately
3.0 per cent of those who had moved did not indicate where they had form
erly lived. Thus the spatial measures of mobility slightly underestimate
the total flows.
The Census Data and Methods of Analysis
In order to test a number of simple hypotheses about the determinants
of migration and the allocation of migrants to various locations, it was
first necessary to develop a series of measures of population size and
other socio-economic characteristics. The most appropriate sources for
the majority of these measures is the 1971 census, which contains a wide
range of relevant variables which are also available for the same set of
spatial units as the migration data. Over 1000 counts of various sub
populations were available, and after selection of the most relevant ones,
and the aggregation of many categories, about two hundred potential measures
remained. From this list those measures put forth in testing the following
hypotheses about migration were selected. These variables will be dis
cussed as they are introduced in various analyses, but Appendix A (Table A.l)
defines them precisely.
Although it may be inappropriate to use measures defined at the end
of the migration period as proxies for regional characteristics throughout
the migration period, one has little choice. It can be argued that most
of the characteristics -- such as economic base, ethnicity and educational
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structure -- will remain relatively the same over time, although some
measures such as the rate of unemployment fluctuate rapidly (see below).
In most centres the inter-urban migrants replace only 10 to 20 per cent
of the population, and do not of themselves radically alter the population
composition,at least in the short run. Nonetheless, some measures, such
as demographic composition, are sensitive to differences in migrant levels.
Rapidly growing or declining places will be affected to the greatest degree.
In addition a number of non-census measures were developed for parti
cular analyses in order to evaluate the role of various natural amenities
and accessibility in explaining migration. These measures are defined in
the Appendix (Table A.2). Another set of variables developed to analyze
the dyadic matrices (124 x 124) of flows among urban places is presented
in Table A.4.
The data analyses consist of a series of correlations and regressions
carried out using the SPSS package. While some attempt was made to formu
late and test a series of hypotheses, the process rapidly became more in
ductive than deductive. The following results describe migration as it
took place in Canada during the period 1966-1971, but generalizations to
other places and other points in time would likely be invalid. Moreover,
several of the fundamental statistical assumptions required for inference
from regression have been violated. The collinearity among the 'independ
ent' variables will be referred to frequently, and its confusing effects
will become obvious. More serious and less apparent is the root cause of
some of these collinearities; that is, the spatial autocorrelation of many
of the variables. The fundamental differentiation of the data observations
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(and of Canada) into two distinct spatial groups, one region with high
levels of migration turnover (Montreal and West) and one of low turnover
(East of Montreal), leads to an association between variables that have
the same spatial structure, but no necessary causal relationship. Other
kinds of basic spatial structure may also intervene, such as the core
periphery difference. In addition, a variance-sensitive analysis such as
this picks up the peculiarities of economic development and population
growth during the study period. The Canadian urban system has a large
random component through time, but this random (over time) component can
itself contain a powerful spatial structure.
This paper does not undertake to review the migration literature.
An excellent and recent review of migration theories is provided by
Greenwood (1975), and phenomena peculiar to Canada are discussed in a
report by Canada Manpower and Immigration (1975). For the most
part though, it will be evident that the hypotheses emerge from a wide
variety of sources rather than any single study.
MIGRATION RATES
From the migration information now available it is possible to gen
erate measures of many different aspects of mobility (Table 2). For the
set of 124 urban regions the number of movers of a particular kind has
been converted into a movement rate by subdividing by a base population
(POPBAS) which is defined as follows: (the 1966 population + the 1971
population age 5 and over)/2. Many of these movement rates were mapped
in the earlier study (Simmons, 1977).
CODE
1. MOVER
2. IN MIG
3. OUT MIG
4. GROSS MIG
5. NET MIG
6. MIG EFF
7. NAT INC1
8. IMMIG
9. LOG POP 66
10. POPBAS
11. GROWTH
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TABLE 2
MEASURES OF MOBILITY
DEFINITION
(Population over 5 in 1971 - the number of non-movers since 1966)/POPBAS
(In-movers from other urban regions)/POPBAS
(Out-movers to other urban regions)/POPBAS
IN MIG + OUT MIG
IN MIG - OUT MIG
NET MIG/GROSS MIG (Migration Efficiency)
(Births - Deaths)/POPBAS
Net Immigration = (GROWTH - NET MIG - NAT INC)/POPBAS
Log 10 (1966 Population)
(1966 Population + 1971 Population over 5)/2
(Population 1971 - Population, 1966)/Population 1966
1obtained from Statistics Canada, 1973
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Table 3 suTIIlilarizes the relationships among the various measures of
mobility. It differs from Table 2 in the previous study in several minor
ways: the use of the averaged base population instead of the 1966 popula
tion; the correction of minor data errors such as the level of in-migration
to Cobourg, and correcting for the effects of boundary changes over time;
the use of estimates of natural increase from vital statistics data (Statis
tics Canada, 1973); and the calculation of net iTIIliligration as a residual
of population growth after natural increase and net internal migration have
been removed.
Despite these changes the results are essentially the same as before.
A typographical correction reverses the sign of the correlation between
city size and turnover. Correlations with net immigration are strengthened
except for the association with city size. Correlations with natural in
crease are weaker, in particular the relationship with growth. A strong
collinearity exists among the various measures of mobility. All, except
perhaps the rate of out-migration, are positively correlated with each
other, and when the rates are mapped the spatial distribution suggests two
different migration regimes: first, east of Montreal almost all cities
are slow-growing and extremely stable with low rates of mobility of all
kinds. Second, Montreal and the rest of the country present a more complex
pattern with high levels of mobility and considerable diversity in the
various components of population growth.
The presence of this collinearity among mobility rates complicates
the analysis of causal relationships as we shall see subsequently. Mobil
ity begets mobility, because those individuals who have changed cities (or
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TABLE 3
CORRELATIONS AMONG MOBILITY RATES
Variable 1 2 3 4 5 6 7 9 10
1. MOVER 1.000
2. IN MIG . 864 1.000
3. OUT MIG .417 .553 1.000
4. GROSS MIG • 775 .929 . 823 1.000
5. NET MIG . 705 . 761 -.119 .466 1.000
6. MIG EFF .708 • 718 -.107 .442 .940 1.000
7. NAT INC • 322 .138 .241 .201 -.023 -.045 1.000
8. IMMIG .661 .584 .252 .Sll .soo .558 -.005 1.000
9. LOG POP 66 -.047 -.387 -.480 -.478 -.088 -.029 -.023 .058 1.000
10. GROWTH • 853 .818 .107 .605 • 892 .850 .287 • 729 -.062 1.000
* * Mean 44.1 14.2 14.4% 28.6 4.5 15.0 5.6 0.7 6.3
Standard 11.6 7.5 4.9 11.0 6.5 18.4 2.9 3.5 9.5 Deviation
Coefficient of 0.26 0.53 0. 34 0.39 1.44 1.23 0.52 5.00 1. 70 Variation
* Absolute values
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countries) a short time ago, are much more likely to move again -- by
virtue of their age (since mobility is highly concentrated in the period
of life-cycle changes, age 15-34), their migration experience, and their
relative lack of social or economic links to any given community. We can
think of rapidly growing communities as containing a large number of
socially mobile economic maximizers, willing to move on to the best offer
at any time. For instance, Cordey-Hayes (1975) presents a model in which
high levels of out-migration leave behind job opportunities which in turn
attract in-migrants. In the low migration regime, in contrast, we observe
communities in Eastern Quebec and the Haritimes which are composed of
households whose mobility appears to be less sensitive to economic condi
tions. Older households, home-owning, linked closely by kinship, culture
and language to a region, are the least likely to move -- particularly
when economic opportunities are located far away, in a markedly different
cultural milieu.
Motivations for migration are seldom clearly defined, however,
either in the heads of migrants or in tables of migration flows. There
are those individuals who have to move "to get out of here" at any cost,
and those who will suffer all kinds of indignities to stay. Sometimes
the former coincide with those who have a drive to improve their lives;
sometimes the latter are people whose lives are already relatively com
fortable. The literature on urban growth and migration (e.g. Miron, 1975)
defines two kinds of growth: household-initiated and industry-initiated,
and these growth types in turn may be related to the above migration
regimes. In household-initiated movements the emphasis is on consumption
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rewards -- peace and quiet or urban stimuli, natural amenities, or per-
haps a familiar life-style. Such rewards can lead to a complex migration
pattern with movements to both rural and urban areas in all parts of the
country as people sort themselves out by life-style. Recently an inter
esting phenomenon has been observed: an important migrant stream to Cali
fornia -- that of the 'Okies' in the thirties -- was not household initiated
(Morrison, 1975). These were people who had been forced off their land
in the Eastern Plains by droughts and dust storms, and who looked to Cali
fornia as a place of work. Forty years later, as they retire, they are
moving back to Oklahoma and Missouri seeking the way-of-life they have
missed. Vanderkamp (1973) suggests that as many as one quarter of Canada's
interprovincial movers are return migrants. Consumption choices are di
verse, and ephemeral. They include the option of staying as well as the
option of moving, and like any consumer decision are linked inextricably
to the costs and rewards of moving.
It is also important to recall that very large adjustments to house
hold preferences can occur without necessarily requiring or initiating job
creation. Only about 13.4 per cent of all moves (gross migration) result
in net migration: the othempermit adjustments of individual households
to life styles and amenities. As emphasized in the previous study these
adjustments reflect patterns of social integration, the distribution of
opportunities and the awareness of these opportunities.
The industry-initiated flow treats the household as responding simply
to differentials in levels of employment and wages between cities and re
gions. The growth of jobs follows the logic of location theory. In
Canada these changes in jobs often reflect massive external stimuli. The
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decline in copper prices leads to the closing of a mine, and people
move away. The household tends to choose locations of higher wages and
greater employment probability. Again, the migrant pattern can be quite
complex, only in this case we observe differential flows due to the diver
sity in the kinds of jobs and occupations involved. Miners move here,
professors there, and executives to somewhere else. A career cycle of
moves may occur -- to military service, to college, to a large city head
office, to the branch plant, etc. Even where the direct inducement of
employment gain is not immediately apparent, the argument of generational
mobility may be involved, with "greater opportunities for the children",
linking social and geographical mobility over two generations. We have
other situations in which the temporal lag between such events and the
migration response is very long. A community of aging miners will not
necessarily change as the mine shuts down. Instead, over twenty years,
we may simply observe that all the young people leave year after year.
We have considerable evidence of both household- and industry-
ini tia ted movement. Sociologists (e.g. Morrison, 1975) have documented
the former; economists (Courchene, 1974; Grant and Vanderkamp, 1976)
the latter. A complex system of tradeoffs links the two sets of motives,
so that unattractive areas (an Arctic weather station) require high wages
and attract an atypical subset of workers, while attractive locations
(a Nova Scotia coastal village or a town in the B.C. interior) can be main
tained with no visible economic support. As the general level of income
and the availability of transfer payments increase, we can posit a relax
ation of the importance of industry-initiated forces in migration.
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There is also some evidence that the two stimuli are not perfectly
linked. Imperfections in the labour market, for example, due to the
costs and time requested in adjustment, maintain deficits or surpluses
of jobs in both attractive and unattractive areas. Governments attempt
to increase the efficiency of the market by encouraging the migration of
either jobs or workers; but they have also enlarged the imperfections by
separating the ties between production and consumption -- providing in
come where there is no net output of goods and services. Moreover, com
panies transfer workers with little reference to current labour market
conditions.
The sections to follow apply some of these hypotheses to the various
measures of mobility rates. First we explore factors linked to the basic
rates of out-migration and in-migration, followed by a brief discussion
of the composite measures of net migration, gross migration, and migration
efficiency. In the final section of the paper the various components of
population growth, including natural increase and immigration, are linked
together into a composite model. Note that Table 3 indicated much greater
levels of variation among the regions in net migration rates than in
either of the other two sources of population growth, natural increase
and net innnigration.
Out-migration
Prior to the 1960 Census of the United States, only very limited
data were available on the rates of in and out-migration for various
spatial units. Wolpert (1965), for example, used the 1960 data to develop
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a series of hypotheses about migration decisions in which the age-
structure of the region played an important role. For Canada the age
distribution of inter-municipal movers is described in Figure 2. The
appropriate hypothesis to test this relationship is:
Hl: The rate of out-migration is directly proportional to the proportion of population aged 15 to 34.
Unfortunately our data file does not include the age-structure of the
population at the beginning of the time period (1966), and since in-
migrants are (naturally) disproportionately young, the measure used here
picks up part of the correlation between in-migration and out-migration
which was noted above (r = .553). Wolpert also introduces the notion of
place utility in which different kinds of households have differing in-
tensities of relationships with their environments. Grant and Vanderkamp
(1976, p. 25), concede the importance of 'taste differences' and specifi-
cally identify French language as a variable in Canadian migration patterns.
Our hypothesis is:
H2: The rate of out-migration is lower for areas which are a) French-speaking, b) spatially isolated, c) settled for a long time, d) characterized by low-levels of education/occupation.
The attempt here is to pick up the marked variations in migration between
the eastern and western parts of the country. One expects that these
characteristics will require much stronger pressures to initiate high
levels of out-migration; whether the relationship is causal or simply a
series of coincidental correlations remains moot.
Accessibility is suggested by Stone (1969) as a critical variable in
migration, which can be defined in any number of ways. The measure used
E N
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FIGURE 2
E
I L61 'dnOJD aoo ~o UO!+o1ndOd /S+UOJD!W JO ·oN
0 U)
0 I()
0 v
0 !'(')
0 C\I
Q
0
c > .... Q.) -c:
-c: Q.)
E Q.)
> 0 E
..... 0 ~ c: c: c: ~ Q.) .c -0 Q.)
~ <(
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here is a form of population potential:
POP POT. 1
E j
-~-b d ..
1]
where bis equal to 1.5 and d .. is assigned the value of 20 miles. The 11
reason for this choice is elaborated in Appendix A.2.
We might also expect the level of out-migration to be related to
the economic performance of a region -- as hypothesized (but not found)
in a number of previous studies (Sjaastad, 1962; Lowry, 1966; and by
Courchene, 1970 and Grant and Vanderkamp, 1976, in Canada). Two measures
are available -- wage rates and the level of unemployment. The former
tend to be a long-s~anding measure tied to the long-term growth trends
of regions. The latter is a highly volatile measure, as Figure 3 suggests,
fluctuating widely both seasonally and through the business cycle. As
Table 4 ind:i.cates (and Grant and Vanderkamp found), unemployment is an in-
effective predictor of migration and a third, intermediate measure was
tried, called the employment ratio (ER). It combines the participation
rate (with links to income, demography and industrial structure) and the
level of unemployment:
H3: Out-migration rates decline as wage rate and employment rate increase.
Renshaw (1975) has looked at the relationship between in-migration, out-
migration and economic growth in some detail, using annual dat~. By thus
controlling for age structure and localized sources of high mobility, he
is able to show that employment growth alters in-migration and out-migration
in opposite directions.
30C
20C
150
'" 150
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FIGURE 3
SEPT I LE ( Saguenay County)
Average weekly wage ( $ )
( 1961 - 100 0)
100 1977
BRANTFORD (BRANT COUNTY) 300
Average weekly wage ( $ )
200
150
100
200 Employment index
150
( 1961 1000)
1969 1970 1971 1972 1973 1974 1975 1976 1977
RED DEER, ALBERTA
200 Average weekly wage ($)
150
iOO 90 80
250 Employment index
200
250 ( 1961 - 100.0)
100 -.----~·-----,--...-1969 1970 1971 1972 1973 t:F4 1975
- 19 -
TABLE 4
THE CORREL.ATES OF OUT-MIGRATION RATES
Variable
1 2 3 4 5 6 7 8 9 10
1. AGE 15-34 1.000
2. FRENCH .503 1.000
3. ACCESS .190 .230 1.000
4. DECADES -.033 .230 .560 1.000
5. UNIVERSITY .081 -.469 .215 -.054 1.000
6. WAGE .488 -.139 .240 -.118 .509 1.000
7. EMPLOYMENT -.403 -.652 -.019 -.027 .277 .013 1.000
8. EMPLOYMENT RATIO -.163 -.694 .119 -.079 .544 .398 . 775 1.000
9. LOG POP 66 .170 .001 .578 .399 .435 .253 -.051 .130 1.000
10. PRIMARY -.079 -.094 -.573 -.602 -.301 -.327 -.152 -.040 -.449 1.000
11. OUT MIG -.114 -.375 -.483 -.649 -.096 .093 .253 .311 -.480 .495
12. Gi\OSS MIG -.051 -.465 -.357 -.601 .287 .306 .260 .423 -.478 .237
13. NET MIG .090 -.229 .128 -.039 .352 .391 .062 .256 -.088 -.356
14. MIG EFF .072 -.301 .210 .210 .054 .426 .471 .204 .411 -.421
Mean 31.1% 30.2% 4901 10.8 7.1 $4859 91.9% 51.2 20.0
Standard 2.6 36.0 4900 4.45 2.3 740 2.8 6.0 10.7 Deviation
Coefficient .08 1.19 1. 00 0.41 0.32 0.15 0.03 0.12 0.53 of Variation
- 20 -
The final hypotheses derive from various descriptions of the Canadian
urban system (Simmons, 1974a, b, 1976). It was observed in these studies
that the largest cities are the most stable, changing slowly and providing
the most diversified economies. The most unstable economies, prone to
rapid growth and decline, occur in the small resource-based regions. Also
we know that primary producing regions have been most directly affected
by the loss of employment due to technological change. The resulting
hypothesis is:
H4: Out-migration rates are ~elated inversely with population size, and directly with the proportion of employment in the primary sector.
A quick overview of the results is provided in Table 4. Out-migration
is obviously complex. Hypothesis one, involving the role of young adults
in out-migration rates, is apparently rejected as the sign is in the wrong
direction. This test is complicated, however, by the collinearity between
the variables AGE 15-34 and FRENCH language (r = .503) and the economic
measures WAGE and EMPLOYMENT. These relationships bedevil the basic be-
havioural hypothesis throughout the study. The high rate of natural in-
crease in French-speaking Canada stopped abruptly in the 1960's, leaving
a population bulge of young adults. The first part of the second hypothesis,
represented by the variable FRENCH (r = -.375), is weakly upheld subject
to the difficulties noted above, that UNIVERSITY and FRENCH are inversely
correlated. Although the level of education (UNIVERSITY) appears to be
an ineffective measure, age of settlement (DECADES) is strongly and negatively
correlated with out-migration, supporting that part of the hypothesis.
The correlation of out-migration with ACCESS is relatively high, but in
the opposite direction to that hypothesized. Northern and far Western
- 21 -
cities, the most remote in the system, are characterized by high levels
of turnover.
Hypothesis three is generally unsuccessful. WAGE has a negligible
effect and both measures of EMPLOYMENT are positively correlated with out
migration, negating the hypothesis. It is apparent that only a closely
controlled analysis like Renshaw's (1975) can support the economic hypothesis.
In hypothesis 4 the correlation with population size is -.480 and with
employment in primary activities is .495. Both correlations are higher
than the correlation between the two independent variables, although both
are related to ACCESS. The city size effect suggests that the number of
opportunities -- socially and economically -- within the region is im
portant (and logically, the presence of more internal opportunities means
fewer external opportunities). The relationship with the primary special-
ization and geographic isolation identifies the high turnover typical of
new resource towns, and also the large net transfer of aggregate employ-
ment from primary to tertiary activities.
From these clusters of relationships, and non-relationships, we can
construct some multiple regression models which incorporate combinations
of variables (Table 5), in order to gauge some of the indirect linkages
in migration. As other measures are taken into consideration, the effect
of age structure comes into line with that proposed in hypothesis one.
The rate of out-migration is consistently, albeit weakly, linked to the
proportion of young adults (although this may be an post effect, re-
fleeting the association between in-migration and out-migration rates
noted earlier), The low migration propensity of French-speaking Canadians
shows up consistently as does the age of settlement, and the variables
of hypothesis 4 remain significant. Experiments with combinations of
OUT-MIGRATION:
Variables AGE 15-34
Model 1. .100
2. .217
3. .242
4. .113
Final OUTMIG =
- 22 -
TABLE 5
SELECTED REGRESSION MODELS (Beta Values)
FRENCH DECADE LOGPOP66 PRIMARY
-.425
-.484 -.516
-.466 - .. 374 .326
-.344 -.377 -.292 .126
.217 + .454 (AGE 15-34) - 0.063 FRENCH -(.145) (.010)
+ 0.150 PRL~Y (.034)
R2
.148
.405
.488
.559
0.045 lO<?EOP 66 (. 009)
R2 = .488
- 23 -
economic measures, however, proved negative. Overall it is possible to
explain about half the variance in out-migration rates with these variables.
Out-migration appears to be due to long-term social and economic adjust-
ments in society rather than the conditions existing at any one point in
time. Even in a booming community many young people will still seek edu-
cational and occupational opportunities elsewhere.
In-Migration
In-migration rates vary more than out-migration rates. As a result
the variations from place to place in level of in-migration account for
the majority of the differences in net migration, turnover and, ultimately
in population growth. This greater variation eases the problem of regres-
sion modelling in some ways, but also forces us to examine a wider range
of independent measures. Stone (1969) undertook a brief exploration of
differences in in-migration rates among urban places in Canada. The re-
sults, however, were not promising. The independent variables, mostly
measures of economic specialization and income, explained only 28 per
cent of the variance. Moreover the differences in the results for urban
subsystems across the country were considerable. We can re-evaluate his
hypotheses here.
The first hypotheses centre around variations in economic opportuni-
ties. Migrants are supposed to seek locations which have high wages and
high levels of employment just as these conditions were supposed to
retard out-migration. In addition we must remember that out-migrants also
contribute to employment opportunities. Our hypothesis is:
HS: In-migration increases with the wage level, employment level and employment ratio.
- 24 -
The second set of variables describes various amenities that may act
as positive attractions to migrants, although the positive correlation
between in-migration and out-migration rates suggests that the character-
istics which keep people at home need not be attractive to residents of
other locations. Svart (1976) and Roberts (1974), for example, discuss
the kind of amenities which attract or deter migrants; such as the variety
of urban activities (described by population size), measures of climate
such as temperature, rainfall and sunshine, or terrain measures such as
the presence of the ocean or the mountains. An interesting table has
been prepared by Leven,~ al., (1970) to show that different age groups
respond differently to these environmental attractions. Unfortunately our
data set does not permit this kind of demographic disaggregation. The
final amenity variable used here follows from Robert's (1974) study which
found that mining and industrial cities were unattractive to prospective
migrants. The composite hypothesis is:
H6: In-migration is positively related to average temperature, sunshine, dryness, and the presence of mountains; cities which are large, non-industrial and non-mining attract migrants.
The final hypothesis introduces the complex notion of access.
Places which are relatively isolated must achieve larger thresholds of
attraction in order to attract migrants. Moreover, they draw upon a
limited number of origins.
H7: In-migration rates are higher in more accessible places.
The simple correlations presented in Table 6 support the economic
hypothesis (HS), but weakly -- much as Stone (1969) found. Both high
wage levels and participation rates attract migrants. The fact that
these variables were not significant to out-migrants suggests a pull
- 25 -
TABLE 6
THE CORRELATES OF IN-MIGRATION
Variable 1 2 3 4 5 6 7 8 9 10
1. WAGE 1.000
2. EMPLOYMENT .013 1.000
3. ER .398 . 775 1.000
4. TEMP .155 -.062 . 044 1. 000
5. RAIN . 075 -.261 -.290 . 574 1. 000
6. WET .099 -.312 -.376 .297 .731 1.000
7. MOUNTAINS .165 -.337 -.196 .309 .135 .182 1. 000
8. LOG POP 66 .253 -.051 .130 .060 .025 .060 .166 1.000
9. MFGMNG .408 -.085 .066 .046 .106 .082 -.175 .066 1.000
10. ACCESS .290 .050 .222 .164 .129 .054 -.225 .578 . 427 1. 000
11. IN MIG .389 .217 .417 .147 -.204 -.211 .330 -.387 -.067 -.208
12. GROSS MIG .306 .260 .423 -.003 -.263 -.258 .280 -.478 =-.174 -.357
13. NET MIG .391 .062 .256 .357 -.028 -.052 .297 -.088 .146 .128
14. MIG EFF .471 .204 .411 .391 .011 -.062 .171 -.029 .215 .210
Mean $4859 91. 9% 51.2 14.4 33.7 137.2 .282 16 .4 4902
Standard 740 2.8 6.0 10.7 13.3 25.6 .452 9.8 4900 Deviation --- --
Coefficient of Variation 0.15 0.03 0.12 .74 .40 .19 1. 60 --- .60 1.00
- 26 -
rather than push factor, confirming the empirical work of Lowry (1966),
Courchene (1970) and Grant and Vanderkamp (1976). The amenity hypothesis
(H6) is also confirmed, in part. The mean January temperature appears to
be an important variable, although neither the amount of annual rain nor
the number of rainy days come through strongly. The relationship between
in-migration and temperature (r = .147) is notable because the sign of
the association with out-migration (r -.233) is in the opposite direction,
producing a sizeable net impact. The presence of mountains, in contrast,
increases the levels of both out-migration and in-migration; and simply
reflects rapid growth in B.C. City size has a negative effect on in
migration, contradicting that part of our hypothesis, but reflecting the
earlier conclusion that city size reduces the level of turnover in general.
The variable MFGMNG, measuring levels of manufacturing and mining activity,
seems to be irrelevant. Finally, it appears that accessibility is not a
major factor affecting in-migration rates; again the sign is opposite
from that hypothesized.
These variables in combination present a much stronger set of relation
ships. As Table 7 shows, the successive addition of a new variable en
larges the role of the earlier ones. The result is a reasonably powerful
regression model of in-migration, which includes p0pulation size (LOG POP 66)
as an explanatory variable, despite the fact that hypothesis H6 had been
rejected earlier. Our larger cities simply generate larger numbers of mi
grants within their own boundaries. The combination of wage rates and city
size are particularly effective. The two variables are weakly collinear,
but operate in opposite directions in influencing in-migration rates. One
experiment, using OUTMIG as an independent variable, produced a low beta
- 27 -
TABLE 7
IN-MIGRATION: REGRESSION MODELS (Beta Coefficients)
EMPLOYMENT R2 Variables WAGE RATIO LOGPOP66 MFGMNG TEMP OUTMIG
1. .264 .312 .233
2. .391 .330 -.529 .494
3. .511 .301 -.538 -.259 .549
4. .468 .253 -.449 -.198 .159 .562
5. .494 .303 -.540 -.256 .101 .559
Final
Equation In-migration = 0.225 + .00005 WAGE + 0.301 EMPLOYMENT RATIO
(.0001) (0.084)
-0.259 MFGMNG - 0.538 LOGPOP66
(.052) (.012)
(Standard errors in parentheses)
- 28 -
value suggesting that the covariation between in-migration and out
migration rates stems from common causes rather than a direct inter
dependence. The major environmental variable (TEMP) did not help much
either, but MFGMNG continuously contributed in the hypothesized direction.
The final regression equation explains 56 per cent of the variance in in
migration rates, not much better than the out-migration model, despite
the existence of greater variance than in the former. It is difficult to
specify a model which identifies those small and primary-production
oriented centres which are growing rapidly in the short term. As Stone
(forthcoming) points out, these migrations are responses to specific
'events' rather than prevailing conditions.
Other Mobility Rates
Net migration, gross migration and migration efficiency are simply
combinations of in- and out-migration rates. It is unlikely that any
variables yet unproposed will contribute to their explanation, although
it is possible that some of the measures identified above will become ir-
relevant or accentuated in combination for instance, the relationship
between city size and in/out-migration is cancelled in the case of net
migration. An overview of the correlations was provided previously in
Tables 4 and 6. Each measure, but especially net migration and migration
efficiency, is linked more closely to in-movement rates than out-movement
rates. Net migration (NET MIG) and migration efficiency (MIG EFF) are so
highly collinear (r .940) that essentially the same relationships hold
for both, although the associations of MIG EFF tend to be slightly stronger.
When Stone (1969) looked at net migration (combining internal and inter
national) patterns for urban centres in Canada over the period 1951-1961,
- 29 -
the strongest correlations were with population size and the demographic
structure - reflecting growth in the previous decade. When the analysis
was repeated using counties as units of observation, the size of popula
tion (or urbanization) was the most significant measure.
The strongest linkages for NET MIG are economic measures, particular
ly WAGE level (r = .391) and the participation rate (.256), while the
strength of the primary sector leads to negative levels of net migration
(-.356). TEMP (.357) is also significant. The education variable
(UNIVERSITY) is also positively linked with net migration, but a negative
association exists with FRENCH. As suggested earlier, population size,
AGE 15-34, ACCESS and MFGMNG appear to be irrelevant. Methodological
differences aside, the results differ markedly from Stone's (1969) find
ings, suggesting that different growth factors dominate in different
decades.
Gross migration or turnover is strongly and inversely correlated
with population size (r =-.478), as might be expected, but is positively
correlated with the dominance of the primary sector (r = .237). The
weakly negative relation with the demographic variable AGE 15-34 (r = -.051)
suggests that we must wait and see how it operates in combination with
other variables before drawing any firm conclusions. The hypothesized
relationship with FRENCH ethnicity is supported (r = -.465), as is age
of settlement (DECADES, r = -.601). Weakly positive relationships with
the economic growth variables are also apparent.
In Table 8 a series of multiple regression models express some of
the indirect effects of these variables. Equation 2 in part a) of the table
again exhibits the complementarity between economic measures and population
a)
b)
- 30 -
TABLE 8
REGRESSION MODELS: NET AND GROSS MIGRATION (Beta Values)
Net Migration
WAGE EMPLOYMENT LOGPOP66 PRIMARY RATIO
1 .392 .126 -.203
2 .276 .177 -.371 -.425
3 .255 .175 -.364 -.352
TEMP
.239
NETMIG = 0.093 + .00002 WAGE + 0.183 EMPLOYMENT RATIO
(.00001) (.083)
-0.055 LOGPOP66 - 0.214 PRIMARY + .00141 TEMP
(. 013) (. 051) (. 00044)
Gross Migr«tion
EMPLOYMENT
R2
.204
. 377
.390
WAGE RATIO LOGPOP66 AGElS-34 FRENCH DECADE R2
1 .309 .379 -.605 .544
2 .348 .353 -.601 -.061 .546
3 .281 .128 -.588 -.137 -.406 .603
4 .244 .193 -.446 .053 -.250 -.320 .675
5 . 271 .198 -.441 -.215 -.328 .674
Final Equation
~ GROMIG = 0.607 + .00004 WAGE + .359 EMPLOYMENT RATIO '\ '\
(.00001) (.149)
-.120 LOG10POP - .0659 FRENCH - .00812 DECADE I\ "\ \
( .016) (.0237) (.00152)
- 31 -
size operating on NETMIG. In combination each variable gains some ex
planatory strength. By and large non-economic predictors of net migration
are ineffective, however, and the final model is both parsimonious and
weak in explanatory power. It can be argued, though, that short-term
variables dominate the relationship.
The gross migration equations are richer in complexity and in ex
planation. The addition of the variable FRENCH to the economic measures
permits age structure to operate as hypothe5ized, but the addition of
age of settlement negates the demographic relationship. Population size
remains as a major determinant of overall levels of migration, suggesting
that continuing increa5e5 in the level of urbanization of Canada may
reduce the amount of inter-regional adjustment which is required for
more balanced growth. French language and age of settlement also
dampen the overall turnover. The model in part b) of Table 8 is reason
ably effective, by the standards of this paper, explaining about two-thirds
of the variation in turnover. Nonetheless the high levels of covariation
among independent variables make the overall results rather suspect. We
know that the level of turnover in Canada differs in our two macro regions,
but we may not understand it any better than we understand net migration
patterns among urban places.
- 32 -
MIGRATION FLOWS
Now that we have some feel for those factors which determine the
number of migrants who begin or end their moves in various locations,
we can investigate the links between the origins and destinations them
selves. It would be possible to satisfy the movement requirements of
Canadians in an infinite number of ways: for instance, by linking only
neighbouring places, or integrating the entire nation. Alternatively we
could imagine migration to be largely confined to regional subsystems,
or perhaps with the most intense flows among major metropolitan centres
across the country.
The data mapped in the earlier paper (Simmons, 1977) describe the
significant patterns of migrant flows. The distribution of flows is
highly skewed, with a large number of zero linkages and a few very strong
linkages. Large cities dominate. Regional differences in migration rates
also affect flow patterns. The significant flows are concentrated in
three spatial clusters, around Montreal, around Toronto and in Western
Canada. Population size and the distance separating places, as combined
in the urban hierarchy, are clearly significant determinants of flow
patterns. Finally the matrix of migration flows is strongly symmetrical,
with net migrants accounting for less than 15 per cent of the total move-
ment.
Spatial interaction can be modelled in either of two ways: we can
observe the individual unit (e.g. the household) as a goal-seeking entity,
and we can try to see how it responds to its environment by moving or
otherwise adapting. These models are essentially behavioural, focussing